JP2002014488A - Toner and electrophotographic apparatus - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A high-density color toner that does not use oil can achieve both high translucency and anti-offset properties, and can maintain high-performance developability even when waste toner is recycled. It is another object of the present invention to provide a toner capable of preventing occurrence of filming on a photoreceptor due to lowland fog. SOLUTION: An external additive consisting of a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability and further inorganic fine particles B exhibiting negative chargeability is externally added to a toner base exhibiting negative chargeability. And mechanical and / or thermal surface treatment of the toner matrix to which the fatty acid metal salt is externally attached.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a laser printer, a plain paper FAX, a color PPC, a toner used in a color laser printer and a color FAX, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art In recent years, electrophotographic apparatuses have been shifting from office use to personal use, and techniques for realizing miniaturization, maintenance-free operation, and the like are required. Therefore, conditions such as good maintenance properties such as recycling of waste toner and low ozone exhaust are required.

A printing process of an electrophotographic copying machine and a printer will be described. First, an image carrier (hereinafter, referred to as a photoconductor) is charged for image formation. As the charging method,
One that uses a corona charger conventionally used,
In recent years, there is a method of uniformly charging the surface of the photoconductor by a contact type charging method in which a conductive roller is directly pressed against the photoconductor in order to reduce the amount of generated ozone. After charging the photoreceptor, in the case of a copying machine, light is radiated to a copy original and reflected light is radiated to the photoreceptor through a lens system. Alternatively, in the case of a printer, an image signal is sent to a light emitting diode or a laser diode as an exposure light source, and a latent image is formed on a photoconductor by turning on and off light. When a latent image (high or low surface potential) is formed on the photoreceptor, the photoreceptor is visualized by toner (having a diameter of about 3 μm to 12 μm) which is a pre-charged colored powder. The toner adheres to the surface of the photoconductor in accordance with the level of the surface potential of the photoconductor, and is electrically transferred to copy paper. That is, the toner is positively or negatively charged in advance, and is electrically attracted from the back surface of the copy sheet by applying a charge having a polarity opposite to the polarity of the toner. As a transfer method, a method using a conventionally used corona discharger, and a transfer method in which a conductive roller is directly pressed against a photosensitive member with the aim of reducing the amount of ozone generated have been put into practical use in recent years. At the time of transfer, not all of the toner on the photoreceptor is transferred to the copy sheet, but part of the toner remains on the photoreceptor. This residual toner is scraped off by a cleaning blade or the like in the cleaning unit and becomes waste toner. Then, the toner transferred to the copy paper is fixed to the paper by heat and pressure in a fixing process.

[0004] As a fixing method, there are a pressure fixing method of passing between two or more metal rolls, an oven fixing method of passing through a heating atmosphere by an electric heater, and a hot roll fixing method of passing between heating rollers. In the thermal roll fixing method, since the surface of the heating roller and the toner surface on the copy paper come into pressure contact with each other, the thermal efficiency at the time of fusing the toner image to the copy paper is good, and the fixing can be performed quickly. However, in the hot roll fixing method, there is a disadvantage that since the toner comes into pressure contact with the surface of the heating roller in a heated and melted state, a part of the toner adheres to the roller surface and again adheres to the copy paper to cause an offset phenomenon that stains the image. As a method of preventing the offset, the surface of the heating roller is formed of a fluororesin or silicone rubber which is heat-resistant and has a good releasability from the toner, and an anti-offset liquid such as silicone oil is supplied to the surface to form a liquid thin film. A method of coating the roller surface has been adopted. In this method, odor is generated by heating liquid such as silicone oil,
In addition, extra equipment for supplying liquid is required,
The mechanism of the copying apparatus becomes complicated. In addition, in order to prevent offset with good stability, it is necessary to control the supply of liquid with high accuracy, and the copying apparatus must be expensive. Therefore, there is a demand for a toner that does not cause an offset without supplying such a liquid and that can obtain a good fixed image.

As is well known, toner for electrostatic charge development used in an electrophotographic method generally comprises a resin component, a coloring component comprising a pigment or a dye, a plasticizer, a charge controlling agent, and, if necessary, a mold release. It is composed of an additive component such as an agent. As the resin component, a natural or synthetic resin is used alone or in a suitable mixture.

The above additives are preliminarily mixed at an appropriate ratio, heated and kneaded by hot melting, pulverized by an air-flow type impact plate method, and classified into fine powder to complete a toner matrix.
Thereafter, an external additive is externally added to the toner matrix to complete the toner.

In the one-component development, the toner is composed of only a toner. However, a two-component developer can be obtained by mixing the toner and a carrier composed of magnetic particles.

In a color copying machine, a photoreceptor is charged by corona discharge using a charging charger, and thereafter, a latent image of each color is irradiated as a light signal on the photoreceptor to form an electrostatic latent image, and a first color, for example, The latent image is developed by developing with a yellow toner. Thereafter, a transfer material charged to a polarity opposite to that of the yellow toner is brought into contact with the photoconductor, and the yellow toner image formed on the photoconductor is transferred. The photoreceptor is cleaned after removing the toner remaining at the time of transfer, and is then discharged, thereby completing the development and transfer of the first color toner.

Thereafter, the same operation as that for the yellow toner is repeated for toners such as magenta and cyan, and a color image is formed by superimposing toner images of each color on a transfer material. Then, these superimposed toner images are transferred to a transfer paper charged to a polarity opposite to that of the toner, and then fixed to complete the copying.

In this color image forming method, a toner image of each color is sequentially formed on a single photoreceptor, and a transfer material wound around a transfer drum is rotated to repeatedly face the photoreceptor. A transfer drum system in which toner images of each color are transferred in a superimposed manner, and a plurality of image forming units are arranged side by side, and each toner image of each color is sequentially passed through a transfer material conveyed by a belt through each image forming unit. A continuous superimposition method in which a color image is transferred and superimposed is generally used.

On the other hand, as an example of a color image forming apparatus using the continuous transfer system, there is Japanese Patent Application Laid-Open No. 1-250970. In this conventional example, four image forming stations each including a photoreceptor, an optical scanning means, etc. are arranged for forming images of four colors, and the paper conveyed to the belt passes under the respective photoreceptors and the color is transferred. The toner images are superimposed.

Further, as another method of forming a color image by superposing toner images of different colors on a transfer material, each color toner image sequentially formed on a photoreceptor is temporarily superimposed on an intermediate transfer material, Japanese Patent Application Laid-Open No. H2-212867 discloses a method for collectively transferring the toner images on the intermediate transfer material to transfer paper.

[0013]

SUMMARY OF THE INVENTION Recently, from the viewpoint of global environmental protection, the waste toner which has been discarded without being reused in order to reduce the amount of generated ozone and regulate unlimited disposal of industrial waste is reused. There is a need for a low-temperature fixing method that reduces power consumption for fixing. Improvements have been made to toner materials in order to cope with roller transfer methods that generate less ozone, to cope with waste toner recycling, and to cope with low-temperature fixing. Furthermore, high performance toners that can be satisfied simultaneously, not alone, are important issues from the viewpoint of environmental protection.

In a copying machine, a printer, and a facsimile, different types of toners are used for different models having different process speeds. For example, in a low-speed machine, a binder resin material having high viscoelasticity and a high softening point is used in order to improve the offset resistance. Since it is difficult to obtain the heat required for fixing with a high-speed machine,
In order to enhance the fixing property, another binder resin having a different softening point and different characteristics is used. The process speed is related to the copying capacity per hour of the machine, and indicates the peripheral speed of the photoconductor. The conveying speed of the copy sheet is determined by the peripheral speed of the photoconductor. If these different toners can be shared, production efficiency can be increased and toner cost can be significantly reduced.

In the fixing step, the fixing strength, which is the adhesive force of the toner to the paper, and the offset resistance for preventing the toner from adhering to the heat roller are the controlling factors.

The toner melts and penetrates into the paper fibers by heat or pressure from the fixing roller to obtain fixing strength.
Conventionally, in order to improve the fixing characteristics, the binder resin has been improved or a release agent has been added to increase the fixing strength of fixing to paper and prevent the offset phenomenon that toner adheres to the fixing roller. are doing.

In JP-A-59-148067, an unsaturated ethylene polymer having a low molecular weight and a high molecular weight portion in a resin, a low molecular weight peak value and Mw / Mn is used, and a softening point is determined. A toner containing the specified polyolefin is disclosed. It is stated that the fixing property and the anti-offset property are ensured by this. Japanese Patent Application Laid-Open No. 56-1
Japanese Patent No. 58340 discloses a toner mainly composed of a resin composed of a specific low molecular weight polymer component and a high molecular weight polymer component. The purpose is to ensure the fixing property by the low molecular weight component and the offset resistance by the high molecular weight component. In Japanese Patent Application Laid-Open No. 58-223155, 1000
Disclosed is a toner containing a resin comprising an unsaturated ethylenic polymer having a maximum value in a molecular weight region of from 10,000 to 200,000 to 1,000,000 and having a Mw / Mn of from 10 to 40 and a polyolefin having a specific softening point. ing. It is used for the purpose of securing the fixing property by the low molecular weight component and the offset resistance by the high molecular weight component and the polyolefin.

However, when a resin having a low melt viscosity or a low molecular weight resin is used to increase the fixing strength in a high-speed machine, the toner adheres to the carrier during long-term use in the case of two-component development. So-called spent tends to occur. In the case of one-component development, the toner easily adheres to the doctor blade or the developing sleeve, and the stress resistance of the toner decreases. Further, when used in a low-speed machine, an offset in which toner adheres to the heat roller at the time of fixing tends to occur. In addition, blocking occurs in which the toners fuse together during long-term storage.

Depending on the configuration in which the high molecular weight component and the low molecular weight component are blended, it is possible to achieve both the fixing strength and the offset resistance for a narrow range of process speeds, but it is compatible with a wide range of process speeds. It is difficult. To cope with a wide range of process speeds, a certain effect can be exerted by configuring a higher molecular weight component and a lower low molecular weight component. However, in a high-speed machine, the fixing strength can be increased by increasing the low molecular weight component, but the offset resistance deteriorates, and in a low-speed machine, the effect of increasing the offset resistance can be obtained by increasing the high molecular weight component. On the other hand, when the amount of the high molecular weight component is increased, adverse effects such as a decrease in the pulverizability of the toner and a decrease in the productivity are caused.

Therefore, in contrast to a configuration 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 easily generated due to poor dispersion, and fogging to the non-image area occurs. Further, an image chipping such as a brush scrape occurs at the rear end portion of the solid black image portion, thereby deteriorating the image quality. There is also a problem of filming contamination of the carrier, the photoconductor, and the developing sleeve.

In a contact type one-component developing system, an elastic blade for regulating a toner layer is used for a developing roller made of silicon resin or the like, and a supply roller made of urethane resin for supplying toner to the developing roller is used. Fusing and agglomeration due to friction between the supply roller and the developing roller occur frequently, causing image defects. Therefore, when a resin having a high molecular weight is used, an excessive load is applied, and the machine itself is greatly damaged, and productivity is reduced.

As described above, from the viewpoint of protecting the global environment in recent years, it is preferable that the waste toner remaining on the photoreceptor after transfer and recovered by the cleaning means be recycled in the developing step again. However, when the waste toner is recycled, the toner appears to be damaged due to stress applied to the waste toner in the cleaner section, the developing section, and the transport pipe when returning the waste toner to the developing section.

When the waste toner scraped off from the photoreceptor in the cleaning step is recycled by development again, if the internal additive or the colorant is poorly dispersed, the particles with reduced dispersion tend to become waste toner. Strongly, when it is mixed with new toner in the developing device, the charge amount distribution becomes non-uniform, the reverse polarity toner increases, and the quality of the copied image deteriorates.

Further, in a toner to which a low melting point component such as wax is added, filming of the wax on the photoreceptor is promoted, which causes a reduction in life. Also, short-length paper such as a postcard is conveyed by the frictional force with the photoconductor drum. However, for a photoconductor in which filming has occurred, the conveyance force is reduced, resulting in poor postcard passing.

In the transfer method using the conductive elastic roller, the transfer paper is inserted between the image carrier and the conductive elastic roller, and a transfer bias voltage is applied to the conductive elastic roller. The method of transferring the toner on the surface of the image carrier to a transfer sheet is problematic. However, the transfer method using such a conductive elastic roller has a problem that a back stain occurs on the transfer sheet. This is because when the toner on the image carrier is transferred to the transfer paper using the transfer roller, the transfer roller is in contact with the image carrier at a predetermined pressure in a state where there is no transfer paper. This is because the transfer roller is contaminated by the fog, and the transfer roller contaminated by the toner comes into contact with the back surface of the transferred transfer paper. Further, in a toner in which the internal additive is poorly dispersed, the fluidity is reduced, the aggregation of the toner is partially strengthened, and a hollow portion is easily generated at the time of transfer. This is more noticeable when recycling waste toner.

Further, in the transfer drum system, a transfer drum is used to align and overlap toner images of different colors, and this transfer drum is rotated at the same speed with respect to the photosensitive member, and the timing of the leading end of the image is adjusted. By matching, the mutual positions of the toner images of each color when forming a color image are matched. However, in the above configuration, since the paper must be wound around the transfer drum, the diameter of the transfer drum needs to be a certain size or more, and the structure is extremely complicated and high accuracy is required. But it was large and expensive. Strong paper such as postcards and cardboard cannot be used because they cannot be wound around the transfer drum.

On the other hand, the continuous transfer system has an image forming position corresponding to the number of colors, and it is only necessary to pass the paper through the image forming position. Therefore, such a transfer drum is not necessary. In this case, a plurality of latent image forming means such as a laser optical system for forming a latent image on a photoreceptor are required in accordance with the number of colors, and the structure is very complicated and expensive. Furthermore,
Since there are a plurality of image forming positions, it is difficult to obtain high image quality stably because the relative displacement of the image forming units of each color, the eccentricity of the rotation axis, and the displacement of the parallelism of each unit directly affect the color misregistration. there were. In particular, it is necessary to accurately perform positioning between the colors of the latent image by the latent image forming means.
As described in Japanese Patent Application Laid-Open Publication No. H11-209, there has been a problem that an image exposure system as a latent image forming means requires a considerable device and a complicated configuration.

Further, Japanese Patent Application Laid-Open No. 2-2 using an intermediate transfer material
In the example of Japanese Patent No. 12867, in order to form toner images of each color on the same photoreceptor, a plurality of developing units must be arranged around a single photoreceptor. And the photosensitive member has a belt shape that is difficult to handle. Also, if each developing device is replaced during maintenance, matching adjustment with the characteristics of the photoconductor is required, and when replacing the photoconductor, it is necessary to adjust the position with each developing device. Maintenance of the body was also difficult.

However, the intermediate transfer system does not require a complicated optical system, and can be used for rigid paper such as postcards and thick paper. The use of an intermediate transfer belt is flexible, so the transfer drum system, continuous transfer There is an advantage that the size of the device itself can be reduced as compared with the system.

It is ideal that all of the toner is transferred at the time of transfer, but some transfer residue remains. The so-called transfer efficiency is not 100%, but is generally about 75 to 90%. The transfer residual toner is scraped off by a cleaning blade or the like in a photoconductor cleaning process, and becomes waste toner.

However, in the configuration using the intermediate transfer member,
The toner undergoes at least two or more transfer steps from the photoreceptor to the intermediate transfer body and from the intermediate transfer body to the image receiving paper. In a normal single transfer copying machine, for example, 85%
Transfer efficiency, the transfer efficiency is reduced to 72% by two transfers. Further, in the case of a transfer efficiency of 75% in one transfer, 56% or about half of the toner becomes waste toner, so that the cost of the toner is increased and the volume of the waste toner box must be increased. Then, the size of the device cannot be reduced. The decrease in transfer efficiency is considered to be due to ground fogging of the opposite polarity due to poor dispersion and transfer omission.

Further, in the case of color development, the toner layer of four colors is superimposed on the intermediate transfer member, so that the toner layer becomes thick, and a pressure difference from a place where the toner layer is absent or thin is likely to occur. For this reason, the "hollow-out" phenomenon in which a part of the image is not transferred and a hole is formed due to the aggregation effect of the toner is likely to occur.
Further, if a material having a high toner releasing effect is used for the intermediate transfer member in order to surely perform cleaning when the image receiving paper is jammed, the hollow portion will be noticeable, and the image quality will be significantly reduced. Furthermore, edge development is performed for characters and lines, and the amount of toner is increased, and toner particles are aggregated by pressurization, so that hollow holes become more noticeable. In particular, it appears more remarkably in a high-humidity and high-temperature environment.

The electrophotographic apparatus described later has an image forming unit group in which a plurality of movable image forming units for forming toner images of different colors are arranged in an annular shape, and the entire image forming unit is rotated. It is a moving configuration. In addition, it is possible to replace the image forming unit and the intermediate transfer unit. When the service life expires and it is time to replace the unit, maintenance can be easily performed by replacing the unit. Can be obtained. However, since the image forming unit orbits itself, the cleaned waste toner temporarily and repeatedly adheres to the photoconductor, and also separates from and adheres to the developing roller, so that the photoconductor is easily damaged or filmed. However, if the charge rising property is poor in the early stage of development, initial fog is induced.

In fixing the four-color toner image, it is necessary to mix color toners. At this time,
When toner melting failure occurs, light is scattered on the surface or inside of the toner image, the original color tone of the toner dye is damaged, and light does not enter the lower layer in the overlapping part,
Color reproducibility decreases. Therefore, it is a necessary condition that the toner has a perfect melting property and has a light-transmitting property so as not to hinder the color tone. In particular, the need for optical transparency on OHP paper is increasing due to an increase in presentation opportunities in color.

However, with such a resin composition, the offset resistance is reduced when the melting characteristics are to be further improved,
Since not all of the toner is fixed to the paper but the toner adheres to the surface of the fixing roller to cause offset, a large amount of oil or the like must be applied to the fixing roller, which complicates handling and the configuration of equipment.

In the fixing process, a belt fixing method in which a medium heating section and a toner melting and fixing section are separately used for the purpose of flexibility, miniaturization, and shortening of warm-up of the apparatus. Therefore, the size of the apparatus can be reduced by reducing the diameter of the fixing roller. In addition, since the curvature of the paper discharge section is increased, the paper is hardly wound around the belt. Warm-up is reduced due to the low heat capacity of the belt. However, when the toner adds a certain amount of high molecular weight component to prevent high temperature offset and has a certain elastic element, the paper on which the thin vertical line pattern of the toner is drawn when separated from the belt with large curvature The tip offset that the part takes to the belt may occur. Further, if a silicone material or a fluorine material having a strong negative charge is used for the belt, an image disorder in which an unfixed toner image repulses the belt electrostatically before entering the fixing unit is likely to occur. In particular, in a configuration in which the release oil is not applied, the influence of the charging property is likely to occur.

In addition, when a toner having a configuration that enhances gloss and light transmittance of a color image by using a low-melting resin is used, when a toner layer is formed on a developing roller by pressing a doctor blade, fusion is performed. Vertical scratches, reduced cleaning performance and filming of the intermediate transfer member, poor scraping of the cleaning roller of the intermediate transfer member, and improved offset resistance by adding a release agent such as polypropylene or polyethylene. Although there is a method, it must be added in a large amount, which also causes image defects such as filming and color turbidity.

The toner must satisfy the above-mentioned problems comprehensively.

In view of the above problems, the present invention does not reduce the charge amount and fluidity of the developer even when the waste toner is recycled.
It is an object of the present invention to provide a toner and an electrophotographic apparatus which do not generate agglomerates, have a long life, enable recycling development, prevent global environmental pollution and reuse resources.

Another object of the present invention is to provide a toner and an electrophotographic apparatus having a uniform charge distribution and stabilizing an image for a long period of time.

Even when used in the one-component developing method, thermal fusion or aggregation of the toner does not occur, and even when a high-performance binder resin is used, the dispersion of the additives can be performed without deteriorating the resin characteristics. It is an object of the present invention to provide a toner and an electrophotographic apparatus capable of improving a developing property and maintaining a stable developing property.

Also, by using an electrophotographic method using a conductive elastic roller or an intermediate transfer member, it is possible to prevent dropout or scattering at the time of transfer, obtain high transfer efficiency, and avoid filming on the intermediate transfer member. It is another object of the present invention to provide a toner and an electrophotographic apparatus capable of preventing fusion to a cleaning roller.

It is another object of the present invention to provide a full-color electrophotographic toner and an electrophotographic apparatus which exhibit high translucency and gloss by oilless fixing without applying oil. Filming on developing rollers, doctor blades, and intermediate transfer bodies can be avoided even with color toners using low-melting sharp-melt resins. An object of the present invention is to provide a toner and an electrophotographic apparatus that can prevent filming of a body or the like.

In the fixing process using a belt and the belt fixing using a roller having a large curvature with a low fixing pressure and a long fixing nip, the non-wrapping property of the paper around the belt is good. It is an object of the present invention to provide a toner and an electrophotographic apparatus which can prevent chipping of an image leading end caused when a belt and paper are separated due to a large curvature.

[0046]

SUMMARY OF THE INVENTION In view of the above problems, a toner according to the present invention has a toner base comprising at least a binder resin and a colorant and having a negative chargeability, and having at least a fatty acid metal salt and a positive chargeability. This is a toner comprising an external additive composed of inorganic fine particles.

Further, the constitution of the toner according to the present invention is such that a toner base comprising at least a binder resin and a colorant and having a negative chargeability, a fatty acid metal salt, inorganic fine particles A having a positive chargeability, and a negative chargeability. And an external additive comprising the inorganic fine particles B shown in FIG.

The constitution of the toner according to the present invention is such that a fatty acid metal salt is externally attached to a toner base comprising at least a binder resin and a colorant, and the toner base to which the fatty acid metal salt is externally attached is mechanically attached. And / or a toner subjected to thermal surface treatment.

Further, the constitution of the toner according to the present invention is such that a fatty acid metal salt is externally attached to a negative electrode chargeable toner matrix comprising at least a binder resin and a colorant, and the fatty acid metal salt is externally attached. A toner in which a toner base is subjected to a mechanical and / or thermal surface treatment, and the surface-treated toner is externally added with inorganic fine particles having positive chargeability.

Further, the constitution of the toner according to the present invention is such that a fatty acid metal salt is externally attached to a toner matrix having at least a negative electrode chargeability comprising a binder resin and a colorant, and the fatty acid metal salt is externally attached. A toner in which a toner base is subjected to a mechanical and / or thermal surface treatment, and the surface-treated toner is externally added with inorganic fine particles A having positive chargeability and inorganic fine particles B having negative chargeability.

[0051]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present embodiment, in one-component development, an elastic blade such as rubber or metal is brought into contact with an elastic or rigid developing roller under a constant pressure to form a thin layer of toner and to expose the photosensitive layer. In this configuration, development is performed by contact or non-contact with the body. Therefore, there has been a problem that the image density is reduced during long-term continuous use. In addition, the use of a low-melting sharp-melt resin in order to develop glossiness and high translucency of a color image makes it easier to fuse to a developing roller and a doctor blade.

In the one-component developing method, a supply roller made of urethane resin and a development roller made of silicon resin or urethane resin are brought into contact with each other at a fixed bite amount (0.1 to 1 mm), and toner is supplied from the supply roller to the development roller. Supply the toner and form a thin layer of toner on the developing roller using an elastic rubber or metal stainless steel doctor blade, and apply DC or AC with or without contact with the photoconductor to form a toner image. It is suitably used for the developing method for forming. At this time, the supply roller and the developing roller are rotated in the same direction, and the peripheral speeds of the developing roller and the supply roller are set to 1: 1 to 0.8:
The configuration is such that the developing roller is advanced at a rate of 0.2. The developing roller has a surface area of 9.8 × 10 ² to 9.8 × 1
0 ⁴ (N / m ²⁾ electrostatic latent image of the press-contact to the photosensitive member at a pressure of is developed. The elastic blade is 5 × 10 ^{3 to} 5 × 10 ⁵
The toner layer is pressed against the developing roller at a pressure of (N / m ² ) to form a toner layer.

Furthermore, in order to control the amount of toner supplied from the toner reservoir to the amount of toner transported on the developing roller when the toner is transported onto the developing roller, a sponge-shaped supply roller made of urethane resin or the like is used. A configuration provided in contact with the developing roller is adopted.

In order to control the amount of toner supplied from the toner reservoir to the amount of toner transported on the developing roller when the toner is transported onto the developing roller, a sponge-like supply roller made of urethane resin or the like is used. And a configuration provided in contact therewith. This is an effective means for regulating the transport amount of the toner to a fixed amount. However, when the amount of toner transported on the developing roller decreases during long-term continuous use, or when a solid black image is taken, one round of the developing roller is developed with a high density. Is not conveyed, and the density rapidly lowers, which may deteriorate the solid followability. 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 greatly reduced. Therefore, measures were taken to increase the charge amount by increasing the amount of the charge control agent or silica, but the image density tended to decrease further. To further pursue, the charge amount of the toner on the supply roller portion has increased significantly.In other words, the decrease in image density does not mean that the charge amount of the toner has decreased, but the supply roller portion before being supplied to the developing roller. This is because the charging capability has increased and the supply capability from the supply roller to the developing roller has decreased. However, if the material composition is changed so as to reduce the charge of the toner, the scattering of the toner around the developing device increases. Therefore, a configuration that can secure the image density while preventing toner scattering is required. It is also effective to increase the pressing force 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, the toner base is made to be negatively charged, and on its surface, the fatty acid metal salt and the inorganic fine particles exhibiting the positive chargeability, or the fatty acid metal salt and the inorganic fine particles exhibiting the positive chargeability and the inorganic fine particles exhibiting the negative chargeability are externally charged. Addition treatment, furthermore, a structure in which a fatty acid metal salt is externally attached and then subjected to a surface treatment, and furthermore, the surface-treated toner has inorganic fine particles exhibiting positive chargeability, or inorganic fine particles exhibiting positive chargeability. It has been found that the problem can be solved by using a toner having a configuration in which inorganic fine particles having negative chargeability are externally added.

This is to prevent the toner from being overcharged at the supply roller by inorganic fine particles or a fatty acid metal salt exhibiting positive chargeability, and to suppress toner scattering by containing a toner base and an external additive having reverse chargeability. It becomes possible. Further, the image density at the time of continuous use can be stabilized, and the solid followability can be improved. The fatty acid metal salt has the effect of smoothing the transfer state of the toner on the developing roller and stabilizing the transfer state at all times. In particular, it is highly effective in stabilizing the transport state under high humidity. At this time, the amount of charge of the toner on the developing roller by the suction type Faraday cage method is -5.
It is preferably -45 [mu] C / g. -5μC / g
Below the range, toner scattering increases. If it exceeds -45 μC / g, it is difficult to obtain an image density.

Further, in this embodiment, the primary transfer process of transferring the toner image formed on the surface of the photosensitive member to the surface of the endless intermediate transfer member by contacting the surface of the intermediate transfer member with the surface of the photosensitive member. Is repeatedly performed a plurality of times, and thereafter, a secondary transfer process of collectively transferring the overlap transfer toner image formed on the surface of the intermediate transfer member to a transfer material such as copy paper by performing the plurality of repetitions of the primary transfer process is performed. It is suitably used in an electrophotographic apparatus having a transfer system configured to be executed. At this time, the photosensitive member and the intermediate transfer member are pressed against each other at a pressure of 9.8 × 10 ² to 2 × 10 ⁵ (N / m ² ), and the toner on the photosensitive member is transferred. In addition, the toner image formed on the surface of the intermediate transfer member is transferred to the surface of the intermediate transfer member by a transfer member via a recording sheet at 5 × 10 ³ to 2 × 10 ⁵ (N /
m ² ) The toner is transferred onto the recording material by pressing with pressure.

At this time, it is necessary to clean and remove the toner remaining without being transferred to the transfer material at the time of the secondary transfer, and a roller to which a bias is applied, a fur brush, or the like is used. At this time, if the toner is not easily cleaned, the toner may cause filming due to contact with the intermediate transfer member. Further, when the toner removed by the roller is scraped from the roller by a metal plate, the toner is fused to the metal plate, and a scraping defect occurs. In particular, the use of a low-melting sharp-melt resin in order to develop glossiness and high translucency of a color image makes filming and scraping defects more likely to occur.

Therefore, by using the external additive or the surface treatment structure of the toner of the present embodiment, the chargeability of the toner can be stabilized, and the toner has a uniform chargeability, has less ground fogging, and has a low transferability during transfer. Hollow holes can be prevented, and high transfer efficiency can be obtained. Regarding the cleaning property, if the charging property of the toner is too strong to the negative polarity, cleaning failure occurs, which leads to filming and scraping failure. By forming the external additive having good chargeability and lubricity in the cleaning property, the cleaning property is improved and filming and scraping defects can be avoided.

Further, in this embodiment, a plurality of movable image forming units each including a rotating photosensitive member and developing means having toners of different colors for forming toner images of different colors on the photosensitive member are provided. It is composed of a group of image forming units arranged in a ring, and the entire image forming unit group is rotated and moved, and the different color toner images formed on the photoreceptor are transferred to the transfer material in superimposed registration with the color image. It is suitably used in a color electrophotographic apparatus for forming a color image.

Since the image forming unit is configured so that the entire unit revolves while the photosensitive member and the developing roller rotate, the toner may temporarily come into contact with and separate from the developing roller and the supply roller in the developing device. Poor charge build-up in the early stage of development causes background fog.

Further, since the toner moves violently up and down due to the rotation of the image forming unit, the toner tends to spill out of the seal portion. Therefore, it is necessary to further strengthen the seal at the seal portion, and the fusing phenomenon occurs. Occurs, and it becomes a lump, causing image noise of black and white streaks.

Further, a situation in which the waste toner that has been cleaned from the photoreceptor and separated from the photoreceptor temporarily and repeatedly adheres to the photoreceptor always occurs. When the waste toner repeatedly contacts the photoconductor, filming on the photoconductor is more likely to occur, which causes a reduction in the life of the photoconductor.

Therefore, by using the external additive or the surface treatment structure of the toner of the present embodiment, the charge rising property of the toner is improved and uniform chargeability is obtained, and there is no occurrence of background fog at the beginning of development. It is. Further, due to the effect of the surface smoothness, it is possible to suppress the occurrence of a fusion phenomenon at the seal and the occurrence of filming on the photosensitive member.

In the present embodiment, a transfer material is inserted between the image carrier and the conductive elastic roller, and a transfer bias voltage is applied to the conductive elastic roller so that the toner image on the image carrier is removed. Is suitably used for an electrophotographic apparatus having a toner transfer system for transferring the toner to a transfer material by electrostatic force. This is because such a toner transfer system is a contact transfer, and a mechanical force other than an electric force acts on the transfer, so that the opposite polarity toner attached to the surface of the photoreceptor which should not be transferred is transferred or passed. In some cases, toner adhering to the surface of the photoreceptor in a non-paper state contaminates the surface of the transfer roller and contaminates the back surface of the transfer paper.

Therefore, by using the external additive or the surface treatment structure of the toner of the present embodiment, aggregation of the toner is suppressed, overcharging is prevented, and the chargeability is stabilized. And a high transfer efficiency can be obtained. Further, the occurrence of filming on the intermediate transfer member and the photosensitive member can be prevented, and the transfer paper can be prevented from being contaminated by unnecessary toner particles. Further, since filming of toner and free silica on the transfer roller surface can be prevented, image defects caused by retransfer of toner and free silica from the transfer roller surface to the photoreceptor surface can also be prevented. The characteristics can be more suitably stabilized with respect to the small particle size toner.

Further, in this embodiment, the present invention is suitably used in an electrophotographic apparatus having a waste toner recycling system in which the toner remaining on the image carrier after the transfer process is collected in the developing device and reused in the developing process. . Since the waste toner is reused in the development, more overcharged or lower charged toner returns to the development, and the charge is fluctuated by continuous repeated use, resulting in a phenomenon that the image density decreases and the ground fog increases. . Further, since the toner is easily aggregated, clogging is easily caused in the transport pipe. In addition, a mechanical shock is applied to the inside of the cleaning device, a transport pipe connecting the cleaning device and the developing device, and the toner is deteriorated due to mechanical shock, and the film on the photoconductor is recovered from the cleaning device to the developing device. Ming will occur.

Therefore, by using the external additive or the surface treatment structure of the toner of the present embodiment, the aggregation of the toner is suppressed, the clogging does not occur in the transport tube, the overcharge is prevented, and the chargeability is stabilized. Thus, the image density and fog can be stably maintained even when used repeatedly and under low temperature and low humidity, and filming on the photoreceptor can be prevented.

Further, the present embodiment is suitably 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 heat-resistant belt such as a nickel electroformed belt or a polyimide belt having heat resistance and flexibility is used. In order to improve the releasability, the surface layer is made of silicone rubber, fluoro rubber, or fluoro resin. Until now, these fixing belts have been coated with release oil to prevent offset. With the toner having a releasing property without using oil, it is not necessary to apply the releasing oil. However, if the release oil is not applied, the toner tends to be charged, and if an unfixed toner image approaches the belt, the toner may fly due to the influence of the charging. In particular, it easily occurs under low temperature and low humidity. Also, when the toner has a certain amount of high molecular weight component added to prevent high temperature offset and has a certain degree of elasticity, the paper on which the thin vertical line pattern of the toner is drawn is separated from the belt with a large curvature. The tip offset that is brought to the belt may occur.

Therefore, by using the external additive of the toner of the present embodiment or the toner having the composition of the surface treatment and the molecular weight characteristic of sharp distribution, the overcharging property of the toner can be suppressed, and the toner is prevented from jumping due to static electricity with the belt. Can be In addition, it can be prevented by the effect of the molecular weight distribution and the slipperiness of the offset toner whose leading end portion is brought to the belt at the time of separation from the belt.

When an organic photoreceptor is used, a charge transport agent such as stilbene, hydrazone, or triphenylamine compound is dispersed in a polycarbonate resin on the surface, and this is applied to a thickness of about 15 to 25 μm. But,
A phenomenon in which filming on a photoreceptor occurs in a toner using silica treated and coated with a silicone oil-based material, which is a material that is originally difficult to film, appears.

Since the organic photosensitive member having a resin film such as a polycarbonate resin has a strong affinity, the photosensitive member is treated with a silicone oil-based material and coated with a toner using silica. It is considered that filming occurred on the transfer roller and the intermediate transfer member. Pursuing this factor, instead of reacting or adhering to all silica when processing silicone oil-based materials into silica,
When silica was treated with, for example, dimethyl silicone oil, residual components of the dimethyl silicone oil remained, and it was found that the residual amount had a large effect of inducing filming on a photoreceptor or the like. . When the fluidity of the toner is improved, the load on the cleaning property of the residual toner at the time of transfer on the photoconductor is likely to be increased, and the photoconductor,
The configuration is such that filming on the intermediate transfer member is more likely to occur. Therefore, by adding the fatty acid metal salt to the toner base, it is possible to suppress the occurrence of filming and to satisfy the developability and durability.

The toner is prepared by uniformly dry-mixing a binder resin, which is a constituent material, a colorant, and other optional additives such as a charge control agent by premixing, and melt-kneading by heat to obtain a colorant. An internal additive is dispersed in a binder resin, and after cooling, an external additive is externally added to and mixed with a toner matrix, which is a colored fine particle having a predetermined particle size distribution by a pulverizing and classification process, to prepare a toner.

The metal salts of fatty acids are preferably metal salts of stearic acid, palmitic acid, oleic acid and the like. Metals include zinc, sodium, lithium, magnesium,
Calcium is preferred. Particularly preferred are zinc stearate, calcium stearate, sodium stearate and magnesium stearate.

Further, it is preferable that the peak temperature of these melting points at the time of temperature rise in differential scanning calorimetry is 100 to 180 ° C. More preferably, 110-170 ° C,
More preferably, it is preferably 115 to 160 ° C. When the peak temperature is lower than 100 ° C., the storage stability is deteriorated and thermal aggregation is easily caused. In addition, filming occurs on the photoconductor, the intermediate transfer member, and the developing roller. When the peak temperature is higher than 180 ° C., the anti-offset effect decreases.

The BET specific surface area is preferably from 0.1 to 50 m ² / g. When the specific surface area is smaller than 0.1 m ² / g, the filming resistance is reduced, the liberation with the toner is increased, and the image is deteriorated. Insufficient surface treatment reduces the effect by half. If it is more than 50 m ² / g, the dispersibility is reduced and the mixing property with the toner base is reduced. Fixability, filming property, and developability deteriorate.

As the inorganic fine powder, alumina, titania,
Silica is a suitable material. The inorganic fine powder having positive chargeability is treated with aminosilane, amino-modified silicone oil, or epoxy-modified silicone oil. In order to further enhance the hydrophobic treatment, it is also preferable to use a combination of treatment with hexamethyldisilazane, dimethyldichlorosilane, or another silicone oil. For example, dimethyl silicone oil,
It is preferable to treat with at least one of methylphenyl silicone oil and alkyl-modified silicone oil.

As the silane coupling agent,
Dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane,
Examples include allylphenyldichlorosilane, benzylmethylchlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, and dimethylvinylchlorosilane. The silane coupling agent treatment is a dry process in which the vaporized silane coupling agent is reacted with a cloud of fine powder by stirring or the like, or a wet process in which the silane coupling agent in which the fine powder is dispersed in a solvent is dropped. Processed according to the law.

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

The treatment may be performed by mixing the inorganic fine powder and a material such as silicone oil with a mixer such as a Henschel mixer, by spraying a silicone oil material onto silica, or by dissolving the silicone oil material in a solvent. After dispersion and mixing with fine silica powder, there is a method of preparing by removing the solvent. Preferably, 0.1 to 8 parts by weight of the silicone oil-based material is blended with respect to 100 parts by weight of the inorganic fine powder.

At this time, the inorganic fine powder is made of B by nitrogen adsorption.
ET specific surface area 30~350m ² / g are preferred. More preferably, the specific surface area is in the range of 50 to 300 m ² / g, more preferably 80 to 250 m ² / g. When the specific surface area is less than 30 m ² / g, the fluidity of the toner does not improve and the storage stability decreases. Specific surface area is 3
If it is more than 50 m ² / g, aggregation is worsened and uniform external addition becomes difficult. 0.1 to 5 parts by weight, preferably 0.2 to 3 parts by weight per 100 parts by weight of the toner base particles. If the amount is less than 0.1 part by weight, the fluidity of the toner cannot be improved.

Further, the specific surface area ratio of the inorganic fine powder A having positive chargeability and the inorganic fine powder B having negative chargeability is 1: 1 to 1
When the ratio is 70: 1, the specific surface area of the inorganic fine powder A is made larger than that of the inorganic fine powder B. As a result, the stabilization of the charge by the interaction, the maintenance of the rising property of the charge, the cleaning property and the transfer property by the interaction with the fatty acid metal salt are improved, and the disturbance of the image at the time of fixing can be prevented.

When the specific surface area of the inorganic fine powder A becomes small, the effect of charging stability is lost, and the toner is overcharged, which causes a decrease in image density. Charging start-up property deteriorates, fogging,
Improper transfer occurs. Conversely, if the ratio exceeds 70, the mixture of the inorganic fine powder A and the inorganic fine powder B is reduced, the stabilization of charging by the interaction is reduced, and the interaction with the fatty acid metal salt is weakened. The waste toner recycling property and the transfer property are reduced.

The mixing ratio of the inorganic fine powder A having positive chargeability and the inorganic fine powder B having negative chargeability is 50:50.
It is preferable that the inorganic fine powder A having positive electrode chargeability is mixed at a ratio of about 95: 5 so that the addition amount is equal to or more than that. If the proportion of the inorganic fine powder B exceeds 50, overcharging becomes severe and solid followability deteriorates. When the ratio of the inorganic fine powder B is smaller than 5, the chargeability is reduced, and the background fog and the amount of waste toner tend to increase.

The charge amount of the inorganic fine powder is measured by a blow-off method of triboelectric charging with a non-coated ferrite carrier. 100m under the environment of 25 ° C and 45% RH
50 g carrier and 0.1 g of silica etc. in a 1 l polyethylene container.
1 g and mixed at a speed of 100 min ^-1 by vertical rotation.
After stirring for 30 minutes and 30 minutes, 0.3 g was collected and blown with nitrogen gas 1.96 × 10 ⁴ (Pa) for 60 seconds.

In the case of positive chargeability, the value of 5 minutes after stirring for 5 minutes is +1.
It is preferable that the value at 30 minutes after stirring for 30 minutes is +50 to +400 μC / g.
Silica having a charge amount at 30 minutes value of 40% or more of a charge amount at 5 minutes value is preferable. If the rate of decrease is large, the change in the charge amount during long-term continuous use is large, and a constant image cannot be maintained.

In the case of negative chargeability, the value for 5 minutes is -100 to -800.
In μC / g, the value for 30 minutes is preferably -50 to -400 μC / g. The silica having a high charge amount can exhibit its function with a small amount of addition.

By having these charging properties, frictional charging between the toner and the supply roller is overcharged during continuous long-term use,
It is possible to improve the toner conveyance amount on the developing roller and the deterioration of the solid followability, prevent the overcharging, and maintain the high image density and the solid followability. In particular, it works more effectively in a supply roller using a urethane resin. Further, the transfer property is improved, and the cleaning property is also improved. The cohesiveness of the toner can be suppressed, the omission during transfer can be prevented, the image characteristics can be stabilized in continuous use at low temperature and low humidity, and the effect of maintaining the image density can be obtained. Also, the recyclability of waste toner is improved.

Digital high image quality, high color reproduction
In order to achieve both high translucency and anti-offset properties without using offset preventing oil in the fixing roller, a sharp-melt binder resin having a low molecular weight distribution and a narrow molecular weight distribution has conventionally been used. With this configuration, light transmission can be ensured, but since offset occurs, it was necessary to apply oil to the fixing roller. Furthermore, the use of sharp-melt polyester resin makes it extremely difficult to disperse internal additives such as pigments and charge control agents. Inconveniences such as filming, deterioration of charging rise, and reduction in image density due to reduction in charge amount during repeated use occur.

By using a polyester resin as the binder resin of the toner and setting the acid value of the polyester resin to 5 to 30, the chargeability can be stabilized. In addition, toner aggregation can be prevented, and filming on the photoreceptor, the intermediate transfer member, and the developing roller can be prevented even when used continuously for a long period of time. This is because the dispersion of the fixing aid at the time of kneading can be made better, and it is considered that there is an effect that the charge can be maintained at a certain level by the acid value of the positively chargeable silica and the resin. If it is 5 or less, fog tends to increase. If it exceeds 30, the moisture resistance will decrease.

Further, by using a polyester resin having a certain high molecular weight component in combination with the binder resin, high translucency,
We have created a configuration that can ensure high color reproducibility and can extend the offset range to a higher temperature range without the need for a fixing oil. However, in development, a stronger stress is applied to increase the chargeability, and a strong load is also applied in cleaning the intermediate transfer body to increase the cleaning property. Also, in the configuration in which the developing unit itself revolves, the stress applied to the toner is stronger,
It is necessary to withstand these stresses and to exhibit high translucency and gloss at the time of fixing.

[0092] Therefore, the toner base using a polyester resin having a certain high molecular weight component as a binder resin is
A configuration in which a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability, or a configuration in which a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability and inorganic fine particles exhibiting negative chargeability are externally added, and further, the fatty acid metal salt is externally attached A configuration in which surface treatment is performed later, and a configuration in which inorganic fine particles having positive chargeability, or inorganic fine particles having positive chargeability and inorganic fine particles having negative chargeability are externally added to the toner subjected to the surface treatment are also used. By maintaining high translucency by doing, durability, transferability,
It has been found that the recyclability and the charging property can be improved, and the fixing property, the developing property, and the durability can be more excellently compatible.

As the binder resin preferably used in the present 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 anhydride is preferably used. .

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 methyl esters and ethyl esters thereof. Of these, aromatic dibasic acids such as succinic acid, phthalic acid, terephthalic acid, and isophthalic acid, and lower alkyl esters thereof are preferred. It is preferable to use a combination of succinic acid and terephthalic acid, or a combination of phthalic acid and terephthalic acid.

The trivalent or higher carboxylic acid component includes 1,
2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid,
1,2,4-naphthalenetricarboxylic 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, empole trimer acid, acid anhydrides thereof, and alkyl (C1 to C12) esters.

As the dihydric alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4
Diols such as butylene glycol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, glycerin, trimethylolpropane, trimethylolethane, etc. Triols and mixtures thereof can be exemplified. Among them, neopentyl glycol, totimethylolpropane, bisphenol A ethylene oxide adduct, bisphenol A
Propylene oxide adducts are preferred.

Examples of the trivalent or higher alcohol component include sorbitol, 1,2,3,6-hexanetetrol,
4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-
Butanetriol, 1,2,5-pentanetriol,
Glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like can be mentioned.

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 PVC mat resistance and the color of the color material of the color toner.

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

Digital high image quality, high color reproducibility colorization,
In order to achieve both high translucency and anti-offset properties in a belt-type fixing process that does not use oil to prevent offset during fixing, waste toner recycling has been realized.
The molecular weight distribution of the melt-kneaded toner is within a certain range to ensure high transferability in the transfer process using an intermediate transfer body and stable long-term use on the developing roller and supply roller in contact type one-component development. By using a fatty acid metal salt as the toner base and the external additive treatment agent set as described above, good characteristics can be exhibited. Furthermore, a configuration in which a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability, or a fatty acid metal salt and an inorganic fine particle exhibiting positive chargeability and inorganic fine particles exhibiting negative chargeability are externally added, and a fatty acid metal salt is externally attached After performing the surface treatment, furthermore, the inorganic particles exhibiting positive chargeability to the surface-treated toner,
Alternatively, stable electrophotographic development and fixing can be maintained by additionally using a configuration in which inorganic fine particles having positive chargeability and inorganic fine particles having negative chargeability are externally added. In conventional color toners, a sharp-melt binder resin having a small molecular weight distribution and a small molecular weight distribution has been used in order to ensure light transmission. With this configuration, light transmission can be ensured, but since offset occurs, it was necessary to apply oil to the fixing roller.

In the present invention, by providing a high molecular weight component having a sharp distribution, a structure has been created which can ensure high translucency and can prevent offset without requiring a fixing oil.

Specifically, GPC is used as the binder resin of the toner.
The molecular weight distribution in the chromatogram is 2 × 10 ^{3 to} 3
A component having at least one maximum molecular weight peak in a region of × 10 ⁴ , and 3 × 1
0 comprised ⁴ or more molecular weight components with respect to the entire binder resin from at least 5% with the resin.

With this configuration, under the kneading conditions described below,
The molecular weight of the high molecular weight component is cut by the shearing force at the time of kneading, and the molecular weight of the toner after kneading becomes an optimal configuration, and the high molecular weight component of the high molecular weight component that inhibits high translucency can be reduced to ensure high translucency. At the same time, offset can be prevented by the low molecular weight polymer component. Further, it is possible to further improve the dispersibility of a pigment, a charge control agent and the like to be added internally. It can be realized by containing a molecular weight component of 3 × 10 ⁴ or more as a component existing in the high molecular weight region in an amount of 5% or more based on the whole binder resin. If a molecular weight component of 3 × 10 ⁴ or more is not contained, kneading is not performed properly, dispersion is poor, and the effect of preventing offset is lost.

The maximum molecular weight peak of the binder resin is 2 × 10 ³
If it is smaller, the resin becomes too soft, the durability is reduced, and the dispersibility is reduced without applying a shearing force during kneading. When the maximum molecular weight peak is larger than 3 × 10 ⁴ , it becomes a factor for lowering the light transmittance of the OHP.

The maximum peak of the molecular weight of the binder resin is preferably 3% in the molecular weight distribution in the GPC chromatogram.
That is, at least one is provided in a region of × 10 ^{3 to} 2 × 10 ⁴ . More preferably, 4 × 10 ³ to 2 × 1
0 is at least one has constructed ^fourth region.

As components existing in the high molecular weight region,
It is preferable that the binder resin has a molecular weight component of 1 × 10 ⁵ or more based on the whole 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 to 0.5% or more based on the whole binder resin.

Preferably, the components present in the high molecular weight region have a molecular weight component of 8 × 10 ⁴ to 1 × 10 ⁷ in 3% or more of the whole binder resin and do not contain a component of 1 × 10 ⁷ or more. A configuration is preferred.

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

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 1% or more based on the whole binder resin, and a component of 6 × 10 ⁶ or more. Is not included.

If the amount of the high molecular weight component is too large, or if the amount is too large, the giant molecular weight component will remain during kneading, and the light transmittance will be impaired. Also, the production efficiency of the resin itself decreases. Unnecessary scratches are made on the developing roller supply roller to cause vertical streaks in the image.

Further, the molecular weight distribution of the kneaded toner in the GPC chromatogram is 2 × 10 ^{3 to} 3 ×.
At least one molecular weight maximum peak in ¹⁰⁴ regions, is that a structure having at least one molecular weight maximum peak or shoulder in the region of ^{3 × 10 4 ~1 × 10 6} .

Preferably, at least one of the maximum molecular weight peaks present on the low molecular weight side of the toner is in the region of 3 × 10 ³ to 2 × 10 ⁴ in the molecular weight distribution in the GPC chromatogram, more preferably 4 × 10 3 ^The structure has at least one in a region of ^{3 to} 2 × 10 ⁴ .

Further, the position of the maximum molecular weight peak or shoulder located on the high molecular weight side of the toner is at least one in the region of 4 × 10 ^{4 to} 7 × 10 ⁵ in the molecular weight distribution in the GPC chromatogram, and more preferably. Is 6 × 10
^This is a configuration having at least one maximum molecular weight peak or shoulder in the region of ^{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 fixing property is deteriorated and the light transmitting property is deteriorated. descend.

Also, the toner molecules existing on the high molecular weight side
The position of the molecular weight maximum peak or shoulder in the amount distribution is 3
× 10^FourWhen smaller, the offset resistance decreases,
Storage stability deteriorates. Deterioration of developability and waste toner recycling
Curability is also reduced. 1 × 10 ⁶Crushability as it gets larger
And the production efficiency is reduced.

Further, as a component existing in the high molecular weight region of the toner, the content of the high molecular weight component of 3 × 10 ⁵ or more is preferably 10 wt% or less based on the whole binder resin. A large or large amount of components existing in the high molecular weight region of 3 × 10 ⁵ or more is a result of the fact that uniform kneading stress was not applied to the toner constituent materials at the time of kneading and the kneading state became defective. This significantly impairs the translucency. In addition, increase in fog due to poor dispersion, developing roller,
The supply roller is damaged, the toner crushability is deteriorated, and the production efficiency is reduced.

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

Further, 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 defined as Ha, 3 ×
Assuming that the maximum molecular weight peak or shoulder in the region of 10 ⁴ to 1 × 10 ⁶ is Hb, Hb / Ha is 0.1.
15 to 0.9.

When Hb / Ha is less than 0.15, the offset resistance deteriorates, the storage stability decreases, and the result is that the filming on the developing sleeve and the photosensitive member is promoted. If the ratio is larger than 0.9, the developing roller supply roller is damaged, and the pulverizability is deteriorated, thereby lowering the productivity and increasing the cost. More preferably, Hb / Ha is 0.15 to 0.7, and still more preferably, Hb / Ha is 0.2 to 0.6.

Further, even if high translucency can be secured and no fixing oil is required, the toner G is used to prevent offset.
The molecular weight distribution in the PC chromatogram was 2 × 10 ³
At least one molecular weight maximum peak in the region of to 3 × 10 ^4, a configuration having at least one molecular weight maximum peak or shoulder in the region of ^{3 × 10 4 ~1 × 10 6} , molecular weight 3 × 10 ⁴ ~1 × 10 ⁶ Focusing on the molecular weight curve located in the region where the molecular weight distribution is larger than the maximum peak or the molecular weight value corresponding to the shoulder present in the region of the molecular weight distribution. Or 90% of shoulder height
When the molecular weight corresponding to the height of the polymer is M90 and the molecular weight corresponding to the maximum molecular weight peak or 10% of the height of the shoulder is M10, this can be realized by setting M10 / M90 to 6 or less. Further, (M10-M90) / M90
Is set to 5 or less.

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 equal to or less than the value described above (the slope of the molecular weight distribution curve). Is very steep), the ultra-high molecular weight component that is impairing the light transmission is eliminated by cutting during kneading, resulting in high light transmission. Furthermore, the high molecular weight component of the steep peak appearing on the polymer side contributes to the anti-offset property, and it is possible to prevent the occurrence of offset of the color toner without using oil.

Further, when the ultra-high molecular weight component is cut into molecules, it is possible to perform a highly dispersing treatment of an internal additive such as a pigment, a charge controlling agent, a release agent, a fixing aid, etc. Are uniform, have a sharp resolution, and do not deteriorate durability even when used continuously for a long time. Further, fog at the time of recycling waste toner can be greatly reduced. Furthermore, it is possible to prevent a hollow portion at the time of transfer and obtain highly efficient transferability.

When the value of M10 / M90 is larger than 6,
When (M10−M90) / M90 is greater than 5,
The ultra-high molecular weight component still remains, impairing the light transmission. More preferably, the value of M10 / M90 is 5.5 or less,
(M10-M90) / M90 is 4.5 or less. More preferably, the value of M10 / M90 is 4.5 or less, and (M10-M90) / M90 is 3.5 or less.

Further, it is important to use a structure in combination with the molecular weight characteristics of the polyester resin as the binder resin. That is, by kneading a resin having a component present in a certain high molecular weight region, it becomes possible to adjust the resin within the above-mentioned characteristic range. That is, if the binder resin is out of the range of the above characteristics, the toner characteristics after kneading do not fall within the above characteristics.

In order to improve digital image quality and color reproduction, and to use the developing roller and the supply roller in contact-type one-component development stably for a long period of time, an oil for preventing offset is used in the fixing roller. In order to achieve both high translucency and anti-offset properties, and to realize waste toner recycling and high transferability in the transfer process using an intermediate transfer body, the molecular weight composition and By using a fatty acid metal salt as an additive,
Long-term stability can be obtained.

It is also important to define the average molecular weights of the binder resin and the toner. The weight average molecular weight Mwf of the polyester resin as the main component of the toner is 10,000 to 400,000, and the ratio Mwf / M of the weight average molecular weight Mwf to the number average molecular weight Mnf.
When nf is Wmf, Wmf is 3 to 100, and when the ratio Mzf / Mnf of the Z-average molecular weight Mzf to the number-average molecular weight Mnf is Wzf, Wzf is 10 to 2000, and the melting temperature by the 1/2 method using a Koka flow tester. (Hereinafter softening point)
It is preferable to use a polyester resin having a temperature of 80 to 150 ° C, an outflow start temperature of 80 to 120 ° C, and a glass transition point of the resin in the range of 45 to 65 ° C.

The Z-average molecular weight best represents the size and amount of the molecular weight in the tailing portion on the high molecular weight side, and has a great influence on the dispersibility, fixability and offset resistance of the internal additive during kneading. As Mzf increases, the resin strength increases, the viscosity during hot-melt kneading increases, and the dispersibility improves significantly.
Fogging and toner scattering can be suppressed, and the effect of suppressing environmental fluctuations under high temperature, low humidity, and high humidity can be obtained. The increase in Mzf / Mnf is widespread to the ultrahigh molecular weight region.

Preferably, Mwf is 11,000 to 400,000,
15,000 to 400,000, more preferably Mwf of 10,000 to 200,000, Wmf of 3 to 30, and Wzf of 10
~ 500, softening point 90 ~ 150 ° C, outflow starting temperature 8
It is preferable to use a polyester resin having a temperature of 5 to 115 ° C and a glass transition temperature of 52 to 59 ° C as components.

More preferably, Mwf is from 10,000 to
100,000, Wmf 3-10, Wzf 10-100, softening point 90-140 ° C, outflow starting temperature 85-110
It is preferable to use a polyester resin having a glass transition point of 53 to 59 ° C in the range of 53 to 59 ° C.

Mwf of the binder resin is smaller than 10,000, Wmf is smaller than 3, Wzf is smaller than 10,
When the softening point is lower than 80 ° C., the outflow starting temperature is lower than 80 ° C., and the glass transition point is lower than 45 ° C., the dispersibility at the time of kneading decreases, the fog increases, and the durability at the time of recycling waste toner deteriorates. Invite. In addition, kneading stress during kneading is not sufficiently applied, and the molecular weight cannot be maintained at an appropriate value. Further, offset resistance and high-temperature preservability are deteriorated, and further, filming on a cleaning blade or a photoconductor occurs particularly in a high-temperature and high-humidity environment when recycling waste toner.

When the Mwf of the binder resin is larger than 400,000,
mf is larger than 100, Wzf is larger than 2000, softening point is larger than 150 ° C., and outflow starting temperature 120
When the glass transition temperature of 65 ° C. is higher than 65 ° C., the load during the processing of the machine becomes excessive, leading to an extreme decrease in productivity, a decrease in light transmittance in a color image, and a decrease in fixing strength.

By kneading the above-mentioned binder resin with a strong compressive shearing force in the melt-kneading treatment, it is possible to exhibit unprecedented characteristics. By fixing without using oil, it is possible to achieve both high translucency and offset resistance of the color toner. In other words, a binder resin with an unprecedented ultra-high molecular weight component is converted into a low molecular weight ultra-high molecular weight component by a stronger compressive shearing force than before, thereby exhibiting high translucency. The presence of the high molecular weight component also satisfies offset resistance.

Further, since it has an ultrahigh molecular weight component, a high shearing force is applied at the time of kneading, so that the colorant can be more uniformly dispersed, the translucency is improved, and high image quality and high color reproducibility are obtained. can get.

Further, the kneaded toner containing a polyester resin as a component has a weight average molecular weight Mwv of 8,000 to 30.
10,000, the ratio M between the weight average molecular weight Mwv and the number average molecular weight Mnv
If wv / Mnv is Wmv, Wmv is 2 to 100;
The ratio Mzv / of the Z average molecular weight Mzv and the number average molecular weight Mnv
When Mnv is Wzv, Wzv is preferably from 8 to 1200. By kneading the toner in this proper range with a high compressive shearing force, it is possible to achieve both high translucency and offset resistance of the color toner by fixing without using oil.

Preferably, Mwv is 11,000 to 300,000,
More preferably, Mwv is 13000 to 300,000. More preferably, Mwv is 8,000 to 200,000 and Wmv is 2
-30, Wzv is preferably 8-100.

More preferably, Mwv is from 8000 to 10
Preferably, Wmv is 2 to 10, and Wzv is 8 to 50.

Mwv is smaller than 8000 and Wmv is 2
If Wzv is smaller than 8, dispersibility at the time of kneading is not improved, fog is increased, durability at the time of recycling waste toner is deteriorated, furthermore, offset resistance, storage stability at high temperature is deteriorated, and waste toner is further deteriorated. Filming of the cleaning blade and the photoconductor occurs particularly in a high-temperature and high-humidity environment during recycling.

When the Mwv of the binder resin is larger than 300,000,
When mv is greater than 100 and Wzv is greater than 1200, the load during the processing of the machine becomes excessive, which leads to an extreme decrease in productivity and a decrease in fixing strength due to a decrease in translucency in a color image.

Therefore, if the molecular weight of the resin is small, an appropriate compressive shearing force cannot be received from the roller, and the dispersibility of the internal additive in the binder resin cannot be improved, and offset occurs. That is, it is necessary to have a molecular weight of a certain value or more.

When Mwf / Mwv is 1.2 to 10, W
mf / Wmv is 1.2 to 10, Wzf / Wzv is 2.2
This can be achieved by being within the range of ~ 30.

More preferably, Mwf / Mwv is 1.2 or more.
5, Wmf / Wmv is 1.2 to 5, Wzf / Wzv is 3
The range of ~ 20 is preferable.

More preferably, Mwf / Mwv is 1.5
-4, Wmf / Wmv is preferably 1.5-3, and Wzf / Wzv is preferably 3-15.

When Mwf / Mwv is smaller than 1.2 and Wm
f / Wmv is smaller than 1.2 and Wzf / Wzv is 2.
When it is smaller than 2, the compressive shearing force does not work sufficiently, the dispersibility of the internal additive does not improve, and the light transmittance does not improve. Further, when the waste toner is recycled, an increase in fog occurs due to a poor dispersibility. Filming on the photoreceptor is induced by pressure from the blade during cleaning. Further, the fixing property is reduced due to the influence of the high molecular weight component.

When Mwf / Mwv is greater than 10, Wmf
When / Wmv is greater than 10 and Wzf / Wzv is greater than 30, the pressure of the compressive shearing force is excessively exerted, and conversely, the internal additives such as the charge control agent mutually aggregate, leading to a decrease in dispersibility. This leads to reduced waste toner recyclability, reduced image density, and poor transfer. In particular, a salicylic acid metal complex as a charge control agent in the polyester resin shown below,
This phenomenon occurs more remarkably when a benzylic acid metal complex is used.

In a color image that does not use oil, the offset resistance deteriorates, and the dispersibility lowers, causing a decrease in translucency, double image formation due to offset, and image bleeding.

By kneading with a high shear force, characteristics such as fixability, developing property and durability are further improved.

The temperature can be improved by setting the temperature of the roll, the temperature gradient, the kneading conditions of the number of rotations and the load current, and the softening point, outflow starting temperature, and glass transition point of the binder resin under optimum conditions.

The rotation speed ratio of the two rolls is increased from 1.1 times to 2.
When the mixing is performed within the range of 5 times, an appropriate shear force is generated at the time of kneading, the molecular cutting of the binder resin, the dispersibility of internal additives such as a coloring agent, etc. are improved, and the fixability and the developability are improved. In this configuration, the rotation ratio of the roll on the side on which the toner is heated to melt and wind the toner is increased. When the ratio is 1.1 times or less, an appropriate shear force is not generated, dispersibility is not improved, and light transmittance is deteriorated. On the other hand, when the ratio is 2.5 times or more, the productivity is sharply reduced, the dispersibility is not improved, and the developing property is deteriorated.

In this case, kneading is performed under the condition that the ratio of the load current value applied to the two rolls is in the range of 1.25 to 10, so that an appropriate shear force is applied and the dispersibility of the internal additive is improved. Is improved. If it is smaller than this range, the dispersibility is not improved, and the light transmittance is deteriorated. Also, productivity is reduced. Conversely, if it is larger than this range, the load applied to the roller becomes too large, and the ultrahigh molecular weight component becomes too low in molecular weight, so that the offset resistance decreases and offset occurs.

In one roll, the first half (IN side) for supplying the raw material and the second half (OU) for removing the kneaded material are provided.
(T side). On the IN side, the temperature is set higher to melt and wrap the supplied material around the roller, and on the OUT side, the temperature is lowered to give a shearing force to the material to improve the molecular cutting of the resin and the dispersibility of the internal additives. Let it. It is desirable that the area on the OUT side be at least half of the roll. By performing the treatment at a low temperature for a long time, the characteristics are further improved.

The temperature of the roll to be heated on the IN side is set lower than the resin softening point of the binder resin. Preferably, the temperature is set to a temperature lower by 10 ° C. than the softening point, more preferably by 20 ° C.

Since the kneading process is performed between the narrow gaps between the rolls, it can be melted and wound around the rolls even at a temperature lower than the softening point. Thereby, an appropriate shearing force can be applied to the material, and the molecular cutting of the resin and the dispersibility of the internal additive can be improved. If the treatment is performed at a temperature higher than the softening point of the resin, the shearing force during kneading becomes insufficient and the dispersibility of the internal additive becomes uneven. Conversely, 7 above the resin softening point
If the temperature is lowered to 0 ° C. or lower, the resin is conveyed without being completely melted, and the dispersibility and the material drop, resulting in a decrease in productivity.

Further, the temperature of the roll on the IN side is set to a temperature not lower than 50 ° C. lower than the resin outflow starting temperature and not higher than 20 ° C. higher than the resin outflow starting temperature. As a result, an appropriate shearing force acts on the resin, thereby improving the molecular cutting of the resin and the dispersibility of the internal additive. If the treatment is performed at a temperature lower than the temperature at which the resin starts to flow by 50 ° C. or lower, winding becomes impossible, and the material falls, resulting in a decrease in productivity. When the treatment is performed at a temperature higher than the starting temperature of the resin by 20 ° C. or higher, the shearing force on the IN side becomes weak, and the dispersibility of the pigment is reduced.

The temperature difference between the IN side roll and the OUT side roll can be improved by performing the treatment within a temperature range of 90 ° C. lower than the resin softening point to 20 ° C. lower. OUT from IN side
The difference in the temperature of the material conveyed to the side means that the IN side is melted to some extent and the internal additives are dispersed in the resin, which receives a strong shear force due to the low temperature on the OUT side and disperses. The properties can be uniform. Also, molecular cutting of the resin can be appropriately performed. If the temperature is lower than the temperature lower by 90 ° C. than the resin softening point, a load is imposed on the production apparatus and productivity is reduced.
If the treatment is performed at a temperature lower than the resin softening point by 20 ° C. or higher, the shearing force becomes weak due to the temperature difference, and the dispersibility of the internal additive and the molecular cutting property of the binder resin decrease.

The temperature difference between the IN side roll and the OUT side roll is 70 ° C. lower than the resin outflow start temperature, and the characteristics are improved by processing at the resin outflow start temperature. IN
Providing a temperature difference between the material conveyed from the side to the OUT side means that the IN side is melted to some extent and the internal additive is dispersed in the resin, which causes a stronger shear force due to the low temperature on the OUT side. Receiving and uniform dispersibility. Also, molecular cutting of the resin can be appropriately performed. 90 ° C below the resin softening point
When the temperature is lower than the low temperature, a load is applied to the production apparatus, and the productivity is reduced. If the treatment is performed at a temperature lower than the resin softening point by 20 ° C. or higher, the shearing force becomes weak due to the temperature difference, and the dispersibility of the internal additive and the molecular cutting property of the binder resin decrease.

The characteristics are improved by setting the temperature difference between the two rolls (the temperature on the IN side of the roll on the heating side and the temperature on the other roll) to be at least half the glass transition point of the resin. It is preferably at least the glass transition point of the resin.

The glass transition point is a point at which the state of the resin changes from a glassy state to a rubbery state. The glass transition point is controlled by receiving a strong shearing force from the other roll cooled in the transitional state. It is considered that the shearing force is likely to concentrate on the polymer component of the resin and the molecular cutting property and the dispersibility of the internal additive are improved. The reason for setting to た め is that not only the temperature but also the pressure acts strongly. If it is lower than 1/2, the shearing force does not act properly, and the cutting of the resin and the dispersibility of the internal additive do not improve.

The effect is enhanced by providing a temperature difference between the IN side and the OUT side of the roll to be heated and setting the temperature difference to a temperature 20 ° C. lower than the glass transition point of the resin. Preferably, the temperature is set to a temperature lower than 40 ° C. or lower.

If the temperature is lower than that, the stress on the resin is weakened, and the molecular cutting properties and dispersibility of the resin are reduced. Conversely, it has been found that when the temperature is set at a temperature higher by 30 ° C. than the glass transition point, fog tends to increase.
Although details cannot be pursued, it is estimated that aggregation of the internal additive has occurred due to the temperature difference during cooling.

It is preferable that the kneading is performed in a state where the surface temperature of the toner melt film in a state where the binder resin is melted and wound around a roll is equal to or higher than the roller temperature. Preferably, the temperature is 5 ° C. or higher, more preferably 20 ° C. or higher, than the roll temperature.

By increasing the shearing force between the rolls,
The temperature of the molten film tends to increase, but by suppressing the degree of the increase, it becomes possible to generate an appropriate shear force. If the temperature is higher than the roller temperature by 60 ° C. or more, the reaction between the resin and the charge control agent tends to occur. Kneading and crosslinking may occur, which may adversely affect the light transmission.

After the molten film of the toner is formed on the heated roll surface, the heating temperature of the roll is lowered,
The shearing force of the kneading becomes stronger in a molten state. If the temperature range to be lowered at this time is too large, the molten layer of the toner peels off on the roll, and chips are scattered. Therefore, a range from 10 ° C. or higher to a temperature lower by 50 ° C. than the glass transition point of the resin or the softening point of the resin is appropriate.

By treating under the above conditions, high molecular weight molecular cutting during kneading can be performed in an appropriate state, and an internal additive, particularly a pigment and a charge controlling agent can be uniformly kneaded and dispersed.
Particularly, it is possible to realize both the translucency of the color toner and the offset resistance in the fixing without using the oil.

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

Further, the raw material is charged into two rolls, and the phenomenon that the material is scattered and flies in the charging is inevitable. In particular, a charge control agent having a low specific gravity is particularly likely to fly. If the sowing material is not collected by local dust collection or the like, it will contaminate peripheral devices and cause toner contamination. Therefore, it is necessary to devise this raw material input. In this configuration, when the toner constituent material is charged from the raw material supply feeder to between the two rolls, the raw material feeder is inserted from the roll (RL2) on the cooling side, and the charging locations are set to the roll (RL1) on the heating side and the roll. From the closest point of (RL2) to the roll (RL1)
Is dropped on the surface of the roll (RL1) in the range of 20 ° to 80 ° in the direction opposite to the rotation direction of the roll.

The molecular weight of the resin is a value measured by gel permeation chromatography (GPC) using several kinds of monodispersed polystyrene as a standard sample.

The apparatus was HPLC 8120 series manufactured by Tosoh Corporation, and the column was 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 volume 2
For 0 μL, detector RI, measurement temperature of 40 ° C., and measurement pretreatment, a sample is dissolved in THF and then filtered with a 0.45 μm filter to remove a resin component such as silica to measure a resin component. The measurement condition is a condition in which the molecular weight distribution of the target sample is included in a range in which the logarithm of the molecular weight and the count number are linear in a calibration curve obtained from several types of monodisperse polystyrene standard samples.

The softening point of the binder resin was determined to be 1.96 × 10 ⁶ N / P with a plunger while heating a 1 cm ³ sample at a heating rate of 6 ° C./min using a flow tester (CFT500) manufactured by Shimadzu Corporation. applying a load of m ^2, diameter 1 mm,
The temperature at which the piston stroke starts to rise is determined as the temperature at which the piston stroke starts rising from the relationship between the piston stroke of the plunger and the temperature, and the minimum value of the curve and the minimum value of the curve. A half of the difference between the end points is obtained, and the temperature at the point where the minimum value is added to the difference is the melting temperature (softening point Tm) in the half method.

The glass transition point of the resin was measured using a differential scanning calorimeter by raising the temperature to 100 ° C., allowing the resin to stand at that temperature for 3 minutes, and then cooling the sample to room temperature at a temperature lowering rate of 10 K / min. The temperature at the intersection of the extended line of the base line below the glass transition point and the tangent line showing the maximum slope from the rising portion of the peak to the peak of the peak when measuring the thermal history 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. in 5 minutes, rapidly cooled to 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 the sample to be charged into the cell was 10 mg ± 2 mg.

In the present embodiment, a charge control agent is added to the binder resin for the purpose of controlling the charge of the toner. Preferable materials include salicylic acid metal salts or metal complexes, metal complexes of benzylic acid derivatives, and phenylborate quaternary ammonium salts. The metals are preferably zinc, nickel, copper and chromium. The amount of addition is 0.1 to 100 parts by weight of the binder resin.
5 to 5 parts by weight are preferred. More preferably, it is 1 to 4 parts by weight, and still more preferably 3 to 4 parts by weight.

Examples of the pigment used in the present embodiment include carbon black, iron black, graphite, nigrosine, metal complexes of azo dyes, C.I. I. Pigment Yellow 1,
Acetoacetic acid arylamide monoazo yellow pigments such as 3,74,97,98; I. Pigment Yellow 1
Acetoacetic acid arylamide disazo yellow pigments such as 2,13,14,17; I. Solvent yellow 19,
77, 79, C.I. I. Disperse Yellow 164,
C. I. Pigment Red 48, 49: 1, 53:
Red pigments such as 1,57,57: 1,81,122,5,
C. I. Red dyes such as Solvent Red 49, 52, 58, 8; I. Pigment Blue 15: 3 or the like or a blue dye / pigment of phthalocyanine or a derivative thereof
It is blended in more than one kind. The addition amount is preferably 3 to 8 parts by weight based on 100 parts by weight of the binder resin.

Further, the volume average particle diameter of the toner is 3 to 11
μm, preferably 3 to 9 μm, more preferably 3 to 6 μm.
μm. When it is larger than 11 μm, the resolution is reduced and high image quality is not obtained. When it is smaller than 3 μm, toner aggregation is increased and background fog is increased.

The volume average particle diameter of the fixing aid is 1 to 10 μm.
, Preferably 2 to 8 μm, more preferably 2 to 5 μm
It is.

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

The coefficient of variation is obtained by dividing the standard deviation of the toner particle diameter by the average particle diameter. This is based on the particle size measured using a Coulter counter (Coulter). The standard deviation is obtained by calculating the square of the difference from the average value of each measured value when measuring n particle systems (n-
It is expressed by the square root of the value divided by 1).

In other words, the coefficient of variation refers to the degree of spread of the particle size distribution.
If it is less than 10%, or if the coefficient of variation of the number particle size distribution is less than 20%, it is difficult in terms of productivity and causes an increase in cost.
If the coefficient of variation of the volume particle size distribution is larger than 35% or the coefficient of variation of the number particle size distribution is larger than 40%, when the particle size distribution becomes broad, the cohesiveness of the toner becomes strong and filming on the photoreceptor occurs. Easier to do.

When the particle size of the toner is reduced and the distribution width is kept within a certain value, it is necessary to add a certain amount of a fluidizing agent in order to maintain fluidity. Poor dispersibility in kneading also affects fluidity, lowering image quality, preventing good recycling of waste toner, lowering transfer efficiency, and making it difficult to form a uniform toner layer on the developing roller. become. Further, in the two-component developing system, the miscibility with the carrier is reduced, the toner density control becomes unstable, the charge distribution becomes uneven, and the image quality is reduced. Accordingly, a configuration in which the fatty acid metal salt and the inorganic fine particles exhibiting positive chargeability, or the fatty acid metal salt and the inorganic fine particles exhibiting positive chargeability and the inorganic fine particles exhibiting negative chargeability are externally added to the surface of the toner having a reduced particle size, Is a configuration in which a fatty acid metal salt is externally attached and then subjected to a surface treatment.Further, the surface-treated toner has inorganic fine particles having positive chargeability, or inorganic fine particles having positive chargeability and inorganic fine particles having negative chargeability. When the toner is reduced in particle size by the configuration in which the fine particles are externally added, and the distribution width based on the variation coefficient is kept within a certain value, the characteristics can be more suitably stabilized with respect to the small particle size toner.

Further, in this embodiment, a configuration in which a fatty acid metal salt is externally attached to the toner base and a mechanical and / or thermal surface treatment is applied to the toner base to which the fatty acid metal salt is externally attached, thereby improving the developing property. Transferability and cleaning properties can be improved. By fixing or fixing the fatty acid metal salt to the toner matrix by the surface treatment by the surface treatment, it is possible to act together with the toner matrix. Thereby, in the development and transfer steps, the fatty acid metal salt is released from the toner matrix,
The effect may be slightly weaker. The effect can be maintained by the surface treatment. In addition, the surface treatment improves the fluidity of the toner, synergistic with the lubricating effect of fatty acids,
Transferability is improved, filming is avoided, and waste toner recycling is further improved. Although the surface treatment improves the fluidity of the toner by making it spherical, the cleaning requires a lot of work. For example, when the residual toner is removed by a cleaning roller, it is necessary to apply a stronger stress, so that the intermediate transfer body is likely to cause filming. At this time, by treating the surface of the fatty acid metal salt, not only the cleaning property is improved but also filming can be avoided. Further, since the addition amount can be suppressed to the minimum amount, the light transmittance at the time of fixing does not decrease.

A similar effect can be obtained by mixing with inorganic fine particles having negative chargeability and subjecting them to a surface treatment. The negative chargeability of the toner can be stabilized by externally adding inorganic fine particles exhibiting negative chargeability to the toner base, and then performing surface treatment to fix and fix the toner. After that, the positively chargeable inorganic fine powder is externally added to increase the fluidity of the toner, the high lubricity of the fatty acid metal salt, the charge stabilization by the positively chargeable inorganic fine powder, and the improvement of the rise property. Synergistically, it is possible to achieve both characteristics in development, transferability, cleaning performance, and fixing performance.

The surface treatment may be performed after the fatty acid metal salt or the inorganic fine particles exhibiting negative chargeability is externally attached to the toner base, and then the toner base may be dispersed in a dispersed state and subjected to thermal surface treatment by hot air, or may be mechanically processed. It is preferable to perform a surface treatment by a mechanical impact force.

In the thermal surface treatment, it is preferable to treat the toner in a dispersed state with hot air having a temperature higher than the melting point of the fatty acid metal salt of 50 ° C. or higher and the softening point temperature of the binder resin or higher. If the surface of the fatty acid metal salt and the surface of the binder resin are not melted by heat, fixing and fixing are not sufficiently performed, and the above-mentioned effects such as stabilization of charge and transferability cannot be obtained.

The surface treatment by mechanical impact force includes a cylindrical rotating body having irregularities on its surface and rotating at a high speed of 80 m / sec or more at a peripheral speed, and a rotating body outside the rotating body of 0.5 mm. A fixed body fitted with a narrow gap of up to 5 mm and having irregularities on its surface, and a gap between the rotating body and the fixed body, wherein a toner base to which fatty acid metal salts and inorganic fine particles exhibiting negative chargeability are externally attached. It is preferable that the carrier is pneumatically conveyed and subjected to surface treatment by mechanical impact force.

When passing through the space of the gap, the fatty acid metal salt is fixed to the surface of the toner matrix by impact force and heat generation. Therefore, a certain speed and gap are required.
Conversely, if the gap is too narrow, fusion will occur.

FIG. 1 schematically shows the structure of a specific example of an apparatus for performing a surface modification treatment using hot air. Less than,
The operation of such a device will be described.

The particles to be treated (mixture of the toner base and the external additive) 401 adjusted to have a predetermined particle size distribution are supplied from a quantitative supply device 402, and are supplied to a pipe 415 by compressed air 403 generated by compressed air generating means 400. Through the nozzle 404, and is ejected to the outside from a nozzle opening inclined about 45 degrees above the dispersion nozzle 404. Here, two dispersing nozzles 404 are disposed at symmetrical positions on both sides of the hot air generator 405. This is because the particles to be processed 401 are efficiently and uniformly processed by ejecting the particles to be processed 401 from a plurality of nozzles. Hot air 406 is radiated from the hot air generator 405 disposed below the hood 407 toward the opening of the hood 407, and the particles 401 to be processed pass through the hot air 406 while being dispersed. And a surface modification treatment is performed. Here, a heater is used as a means for generating hot air from the hot air generator 405. As means for generating hot air from the hot air generator 405,
For example, by burning propane gas or the like, hot air 4
06 may be used. The surface-modified particles to be treated 401 are taken into the hood 407, sent to the cyclone 410, and collected in the collection box 411.
Collected and collected at. In the figure, 412 is a bag filter for collecting fine powder, 414 is a blower for forming a negative pressure, 413 is an air flow meter for measuring the air volume generated by the negative pressure formed by the blower 414, and 417 is It is a thermometer for measuring the processing temperature.

In order to fix the fatty acid metal salt uniformly and sufficiently, the air volume of the hot air should be 14.7 to 49 ×
At 10 ⁴ Pa, 0.1 to 12.0 m ³ / min, the flow rate of the dispersed air flow for supplying the toner raw material is 4.9 to 29.4 × 1.
In 0 ⁴ Pa, it is preferably performed in 0.01~3.0m ³ / min, conditions. The ratio between the hot air flow rate and the flow rate of the toner raw material supply dispersed air flow is in the range of 10: 1 to 4: 1.
The hot air volume and the ratio of the air volume of the toner raw material supply dispersed airflow are defined as follows: if the hot air volume is too weak relative to the toner raw material supply dispersed airflow, the toner raw material crosses the hot air flow,
Surface treatment cannot be applied uniformly. Conversely, if the amount of hot air is too strong, the toner raw material is blown around the airflow by the hot air flow, and the surface treatment cannot be performed uniformly.

In the present embodiment, the amount of hot air is determined by the air pressure 29.
At 4 × 10 ⁴ Pa, 10.0 m ³ / min, the flow rate of the dispersed air stream for supplying the toner raw material was 1 × at a wind pressure of 9.8 × 10 ⁴ Pa.
The treatment was performed at m ³ / min, a hot air temperature of 300 ° C., and a supply amount of 2 kg / h. This processing condition is indicated as TFS-1.

FIG. 2 illustrates a structure for performing a surface treatment by a mechanical impact force. Reference numeral 200 denotes a main body, and a rotating body 201 having a cylindrical shape is provided at a central portion, and a fixed body 202 having a cylindrical shape is provided outside the rotating body 201. Rotating body 201
Is supported by upper and lower bearings (not shown), and is driven at its lower end by a driving device (not shown). At the lower end of the main body 200, a supply port 204 through which an object to be processed 203 of the toner and an airflow at a predetermined temperature are introduced.
Is provided at the upper end of the main body 200, and a discharge port 205 for discharging the processed toner and the airflow is provided. On the outer surface of the rotating body 201, a number of protrusions 206 parallel to the generatrix are continuously arranged in the circumferential direction.
On the inner surface of the fixed body 202, a number of protrusions 207 parallel to the generatrix are continuously arranged in the circumferential direction. The tip of the projection 206 of the rotating body 201 and the tip of the projection of the fixed body 202 are fitted with a minute gap of 0.5 to 5 mm. When the rotating body 201 rotates at high speed,
The object to be processed together with the high-speed air current flows in a spiral manner at a high speed while forming a minute vortex in the gap, and moves upward, and in the process, the surface treatment of the toner is performed.

The overall flow will be described.
From 08, an object to be processed 203 of a toner base is supplied. The airflow generated by the airflow generation means 209 is set to a predetermined temperature by the heat exchanger 210, passes through the conduit 211, and passes through the supply port 203.
To reach. On the way, the processing object 20
3 is introduced, and flows into the main body 200 by air flow. The processed toner is discharged from the discharge port 205. 212
Is a temperature sensor for measuring the temperature of the discharge section. The processed material discharged from the discharge port 205 passes through the discharge conduit 213 and is collected by the cyclone separator 215.

At this time, the narrow gap between the rotating body and the fixed body is preferably 0.5 to 5 mm. When it is 0.5 mm or less,
The generation of frictional heat increases, and the toner is fused. Also 5mm
In the above case, a strong high-speed flow cannot be generated and processing cannot be performed. At this time, assuming that the glass transition temperature of the binder resin is Tg, the toner outlet ambient temperature of the pulverized portion is Tg−40 ° C.
It is preferable to perform the treatment at a temperature of -Tg + 40 ° C. When processing is performed in this temperature range, uniform processing is performed. When the temperature is higher than this temperature range, the toners are fused together or adhered to the mechanical device, which is not preferable.

In this embodiment, the outlet atmosphere temperature is 45 ° C., the gap between the rotating body and the fixed body is 1 mm, and the rotating body 101 rotates at a high speed of 130 m / sec. 5kg / h
Was supplied. This processing condition is indicated as TFS-2.

The toner is prepared through the steps of preliminary mixing, melt-kneading, pulverizing and classifying, and external addition.

The pre-mixing treatment is a treatment in which the binder resin and the additives to be dispersed therein are uniformly dispersed by a mixer having stirring blades or the like. As the mixer, a well-known mixer such as a super mixer (manufactured by Kawada Seisakusho), a Henschel mixer (manufactured by Mitsui Miike Kogyo), a PS mixer (manufactured by Shinko Pantech), a Reedige mixer or the like is used.

FIG. 3 is a schematic perspective view of the toner melt-kneading process, FIG. 4 is a plan view, FIG. 5 is a front view, and FIG. 6 is a side view. Reference numeral 601 denotes a material feeder, and 602 denotes a roll (RL).
1), 603 is a roll (RL2), 604 is a roll (R
L1) A molten film of the toner wound on the top, 602-1 is the first half of the roll (RL1) (upstream in the raw material transport direction),
Reference numeral 602-2 denotes a second half of the roll (RL2) (downstream in the direction in which the raw material is transported), and reference numeral 605 denotes a first half of the roll (RL1).
An inlet for the heat medium for heating 2-1; an outlet 606 for the heat medium that heated the first half 602-1 of the roll (RL1); and a heater 607 for the second half 602-2 of the roll (RL1) 608 is a roll (RL)
Outlet of the heat medium that heated the latter half 602-2 of 1), 6
Reference numeral 09 denotes an inlet of a heat medium for heating or cooling the roll (RL2) 603, reference numeral 610 denotes an outlet of a heat medium for heating or cooling the roll (RL2) 603, and reference numeral 611 denotes a depth of a spiral groove on the roll surface. Is about 2 to 10 mm, 612
Is a toner pool formed between the rolls. The raw material is supplied from the metering feeder from the end on the roll (RL1) 602-1 side. The resin is melted by the heat of the roll (RL1) 602-1 and the compressive shearing force of the roll (RL2) 603, and the resin is wound around the first half 602-1 of the roll (RL1). That state is the latter half of the roll (RL1) 602-
2 to the first half of the roll (RL1).
It is peeled from the rear half 602-2 of the roll (RL2) heated at a temperature lower than 2-1. Note that, during the above processing, the roll 603 is cooled to room temperature or lower. The clearance between the roll (RL1) 602 and the roll (RL2) 603 is 0.1 to 1.0 mm. Raw material input is 10k
g / h.

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

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. Known mixers such as a Henschel mixer and a super mixer are used for this.

Next, the present invention will be described in more detail with reference to examples.

Table 1 shows the characteristics of the binder resin used in the examples. 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 blending ratio and polymerization conditions was used.

[0200]

[Table 1]

Mnf is the number average molecular weight of the binder resin, Mwf
Is the weight 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, W
zf is the Z average molecular weight Mzf and the number average molecular weight M of the binder resin.
The nf ratio Mzf / Mnf and AV indicate the resin acid value.

Table 2 shows the inorganic fine powder used in this example.

[0203]

[Table 2]

Table 3 shows the characteristics of the fatty acid metal salts used in this example.

[0205]

[Table 3]

Table 4 shows the charge control agents used in this example.

[0207]

[Table 4]

Table 5 shows the pigments used in this example.

[0209]

[Table 5]

Table 6 shows the toner material compositions used in this example.

[0211]

[Table 6]

Each toner has a weight average particle diameter of 6 to 7.
The prototype was manufactured such that the variation coefficient of the volume particle size distribution was 20 to 25% and the variation coefficient of the number particle size distribution was 25 to 30%.

The mixing ratio of the pigment and the charge controlling agent is as follows.
The blending amount (parts by weight) ratio with respect to 00 parts by weight is shown in parentheses. The amounts of the inorganic fine powder and the fatty acid metal salt are shown in terms of the amount (parts by weight) based on 100 parts by weight of the toner base. In the external addition process, the stirring blade Z0S0 type, rotation speed 20
The process was performed at 00 rpm, for a processing time of 5 min, and at a charge of 1 kg.

(Table 7), (Table 8) and (Table 9) show the molecular weight characteristics of the toner after the kneading treatment in this embodiment. The toner was evaluated using a TM toner of magenta toner. Similar results are obtained with yellow, cyan, and black toners. Mnv 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 to 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 / Mn
v.

In the molecular weight distribution, ML indicates the maximum molecular weight peak on the low molecular weight side, MH indicates the maximum molecular weight peak on the high molecular weight side, and MV indicates the minimum molecular weight peak value. Sm is H
b / Ha, Sn is (Hb-La) / (Ha-La),
SK1 is M10 / M90, SK2 is (M10-M90)
/ M90.

[0216]

[Table 7]

[0219]

[Table 8]

[0218]

[Table 9]

FIGS. 11 to 18 show the molecular weight distribution characteristics.

FIGS. 11a and 11b show the binder resin P, respectively.
FIG. 12 shows the molecular weight distribution characteristics of ES-1 and toner TM-1.
12A and 12B show a binder resin PES-2 and a toner T, respectively.
13a and 13b show the molecular weight distribution characteristics of the binder resin PES-3, respectively, and FIGS. 14a and 14b show the molecular weight distribution characteristics of the binder resin PES-.
4. Molecular weight distribution characteristics of toner TM-4, FIG.
5b shows the molecular weight distribution characteristics of the binder resin PES-5 and the toner TM-5, respectively, and FIGS. 16a and 16b show the molecular weight distribution characteristics of the binder resin PES-6 and the toner TM-6, respectively.
FIGS. 7a and 17b show the molecular weight distribution characteristics of the binder resin pes-7 and the toner tm-7, respectively.

In the binder resin PES-1, 3 × 10 ⁴ or more high molecular weight components are present in an area ratio of 5% or more with respect to the entire binder resin molecular weight distribution. Further, a high molecular weight component of 3 × 10 ^{5 to} 9 × 10 ⁶ is added in an area ratio of 1 to the entire binder resin molecular weight distribution.
% Or more. Similarly, PES-2, 3, 4, 5, 6
In addition, 3 × 10 ⁴ or more high molecular weight components are present in an area ratio of 5% or more with respect to the entire binder resin molecular weight distribution. Also 3 × 1
It has a high molecular weight component of 0 ^{5 to} 9 × 10 ^{6 in} an area ratio of 1% or more with respect to the entire binder resin molecular weight distribution. But pes-
In No. 7, the presence of a high molecular weight component of 3 × 10 ⁴ or more is 5% or less in area ratio to the whole binder resin molecular weight distribution, and 3
There are no high molecular weight components of × 10 ^{5 to} 9 × 10 ⁶ .

It can be seen that the kneading of the toner causes molecular breakage in the toner, which appears as a peak or a shoulder on the polymer component side. In other words, the component that is impairing the translucency disappears due to cleavage, and a steep slope appears on the polymer side, which is a factor that maintains the offset resistance without impairing the translucency. 3 × 1 for toner TM-1
0 ⁵ or more high molecular weight component weight is 5% or less in area ratio with respect to the entire toner molecular weight distribution, 1 × 10 ⁶ or more high molecular weight components scarcely contained. Similarly, TM-2, 3,
The amount of the high molecular weight component of 4, 5 and 6 is 3 × 10 ⁵ or more with respect to the whole toner molecular weight distribution in an area ratio of 5% or less.
0 ⁶ or more high molecular weight components scarcely contained.

FIG. 18 shows the molecular weight distribution characteristics. The thick line in the figure shows the molecular weight distribution characteristics of the toner TM-4. It appears as a steep peak on the polymer component side. This is because the high molecular weight component of the binder resin PES4 was molecularly cut by kneading and appeared as a steep peak on the high molecular component side.

Assuming that the peak height of the steep distribution on the polymer side is 100%, the molecular weight curve in a region larger than the maximum peak or the molecular weight value corresponding to the shoulder, that is, the slope of the molecular weight distribution curve in this region is In a negative region, that is, a region on the right side of the distribution curve, when the maximum peak or shoulder height of the molecular weight distribution is 100%, the maximum molecular weight peak or shoulder height is 90%.
% Is M90, and the molecular weight corresponding to 10% of the maximum molecular weight peak or shoulder height is M10. Here, the value of M10 / M90 (the slope of the molecular weight distribution curve) can quantify the state of molecular cleavage of the ultrahigh molecular weight component. When the value of M10 / M90 is small, the slope of the molecular weight distribution curve is steep, and a component that inhibits light transmission is eliminated by cleavage, and the material has high light transmission. Further, the peak appearing on the polymer side contributes to the offset resistance.

(Embodiment 1) FIG. 7 is a sectional view showing the structure of an electrophotographic apparatus used in this embodiment. The apparatus of this embodiment has a configuration in which a FP7750 (Matsushita Electric) copying machine is modified for reversal development and a waste toner recycling mechanism is added.

Reference numeral 301 denotes an organic photoreceptor. A charge generation layer is formed by vapor deposition of oxotitanium phthalocyanine powder on an aluminum conductive support, and a polycarbonate resin (Z-200 manufactured by Mitsubishi Gas Chemical) and butadiene are formed thereon. And a charge transport layer containing a mixture of hydrazone and hydrazone.

A roller 302 negatively charges the photosensitive member.
A charger 303 controls a charging potential of the photoconductor.
A reference electrode 304 is a signal light. 305 is a development three
306 is a doctor blade, 307 is a carrier holding
Roll 308, carrier 309
Is a toner. The carrier is methyl silicone resin,
Phenyl silicone resin, butyl acrylate 2: 6: 2
And coat it on the surface of Mn-Mg ferrite particles.
Was. The average particle size is 40-60 μm and the volume resistance is 10 ¹²Ω
cm. The toners were TB-1, 2, 3 described in Table 5.
It was used.

Reference numeral 310 denotes a voltage generator, 311 denotes waste toner remaining after transfer, 312 denotes a cleaning box, and 313 denotes a transport pipe for returning the waste toner 311 in the cleaning box 312 to the developing step. The transfer residual toner is scraped off by the cleaning blade 314, and the waste toner 311 temporarily stored in the cleaning box 312 is removed.
Is configured to be returned to the developing step by the transport pipe 313.

At 314, the toner image on the photosensitive member is transferred to paper.
Transfer roller, the surface of which contacts the surface of photoreceptor 301
Is set to Transfer roller 314 is conductive
Elasticity provided with conductive elastic members around the shaft made of metal
Roller. The pressing force on the photosensitive member 301 is the transfer roller 3
14 per one (about 216 mm) 0 to 1.96 × 10 ^Five
N / m^Two, Preferably 4.9 × 10^Three~ 9.8 x 10^FourN
/ M^TwoIt is. This is to transfer the transfer roller 314 to the photosensitive member 301.
Measured from the product of the spring coefficient and the amount of shrinkage of the spring for pressing against
did.

The width of contact with the photosensitive member 301 is about 0.5 mm
5 mm. The rubber hardness of the transfer roller 314 is 80 degrees or less, preferably 30 to 70 degrees, as measured by Asker C (measurement using a block piece instead of a roller shape).
If the angle is smaller than 30 degrees, the transfer efficiency decreases and the amount of waste toner increases. If it is greater than 70 degrees, omission during transfer tends to occur. Since the internal additive of the present configuration can be uniformly dispersed, the above range is necessary to sufficiently exhibit the effect.

The elastic roller 314 has a resistance value of 10 ⁷ Ω · cm (an electrode is provided on the shaft and the surface by internally adding a lithium salt such as Li ₂₀ around the shaft having a diameter of 6 mm.
(Applied 500 V to both). The resistance is preferably in the range of 10 ⁵ to 10 ⁹ Ω · cm. If it is smaller than 10 ⁵ , the transfer efficiency decreases and the amount of waste toner increases. If it is larger than 10 ⁹ , omission during transfer tends to occur. Since the internal additive of the present configuration can be uniformly dispersed, the above range is necessary to sufficiently exhibit the effect.

The overall outer diameter of the transfer roller 213 is 16.4 m.
m and hardness was 40 degrees for Asker C. The transfer roller 314 was brought into contact with the photosensitive member 301 by pressing the shaft of the transfer roller 314 with a metal spring. The pressing force is about 9.8 × 10
⁴ N / m ² . As the elastic body of the roller, besides the foamable urethane elastomer, CR rubber, NBR, S
Elastic bodies made of other materials such as i-rubber and fluorine rubber can also be used. As a conductivity-imparting agent for imparting conductivity, other conductive substances such as carbon black can be used in addition to the lithium salt.

Reference numeral 315 denotes a rush guide made of a conductive member for introducing transfer paper to the transfer roller 314, and reference numeral 316 denotes a transport guide in which the surface of the conductive member is insulated. The rush guide 315 and the transport guide 316 are grounded directly or via a resistor. 317 is transfer paper, 318 is transfer roller 3
14 is a voltage generating power supply for applying voltage to the power supply 14.

Table 10 shows the results of the image test.

[0235]

[Table 10]

In the image evaluation, the image density and the background fog were evaluated at the initial stage of image formation and after the durability test after 100,000 copies. The ground fog was judged by visual observation, and it was judged as acceptable (（) if the level was practically acceptable.

Thereafter, an image test of 1,000 sheets was performed while being left under high humidity, and an increase in fog was observed. The toner density control was poor, and the fog increased sharply when the toner was overtoned. Further, in another experiment, the image was allowed to stand overnight under high temperature and low humidity, and an image test was performed on 5,000 sheets the next day. The image density after 5,000 sheets is shown.

There was no horizontal line disturbance, toner scattering, transfer failure or paper back stains, no blackout in characters, uniform solid black images, and high density images with image densities of 1.3 or more. . No ground fogging occurred in the non-image area. There was no filming on the photoreceptor surface, and a high-density, low-ground fog copy image comparable to the initial image was obtained. No fogging occurred under high humidity, and no decrease in density occurred even under high temperature and low humidity.

Table 11 shows low-speed machines (process speed 140 m
m / s) and a high-speed machine (450 mm
/ S). Fixing rate 80%
As described above, there is no practical problem if the high-temperature offset property does not occur up to 180 ° C. In the storage stability test, the state of aggregation of the toner after being left at 50 ° C. for 24 hours was observed. ○ indicates no aggregation and no practical problem, and X indicates a practically problematic level.

[0240]

[Table 11]

The process speed is related to the copy processing capacity of the machine per time, and indicates the peripheral speed of the photosensitive member. The conveying speed of the copy sheet is determined by the peripheral speed of the photoconductor.

A copy paper of 80 g / m ² paper (Igepa) was used, and a patch having an image fixing rate of 1.0 ± 0.2 was wound around Bencott (trademark, manufactured by Asahi Kasei Corporation) in each row.
The paper was rubbed 10 times with a 0 g (φ36 mm) weight, and the image density before and after the rubbing was measured by a Macbeth reflection densitometer, and defined by the rate of change.

The high-temperature offset property at a low speed and the fixing rate at a high speed showed good characteristics, and the high-speed machine and the low-speed machine could be shared by one toner.

(Embodiment 2) FIG. 8 is a sectional view showing the configuration of an electrophotographic apparatus for forming a full-color image used in this embodiment. In FIG. 8, reference numeral 1 denotes an outer casing of the color electrophotographic printer, and a right end face side in the figure is a front face. Reference numeral 1A denotes a printer front plate. The front plate 1A can be freely opened and closed as shown by a dotted line with respect to the hinge shaft 1B on the lower side of the printer outer casing 1, and can be raised and closed as shown by a solid line. The operation of attaching and detaching the intermediate transfer belt unit 2 to and from the inside of the printer, and checking and maintaining the inside of the printer such as when a paper jam occurs, are performed by opening the front plate 1A to open the inside of the printer. The attachment / detachment operation of the intermediate transfer belt unit 2 is designed to be in a direction perpendicular to the rotation axis generatrix direction of the photoconductor.

FIG. 9 shows the structure of the intermediate transfer belt unit 2. The intermediate transfer belt unit 2 includes a unit housing 2a, an intermediate transfer belt 3, and a first conductive elastic body.
A transfer roller 4, a second transfer roller 5 made of an aluminum roller, a tension roller 6 for adjusting the tension of the intermediate transfer belt 3, a belt cleaner roller 7 for cleaning the toner image remaining on the intermediate transfer belt 3, and a cleaner roller 7 It includes a scraper 8 for scraping the collected toner, waste toner reservoirs 9a and 9b for storing the collected toner, and a position detector 10 for detecting the position of the intermediate transfer belt 3. As shown in FIG. 2, the intermediate transfer belt unit 2 can be detached from a predetermined storage portion in the printer outer casing 1 by opening the printer front plate 1A as shown by a dotted line and opening it.

The intermediate transfer belt 3 is used by kneading a conductive filler in an insulating resin and forming a film with an extruder. In this embodiment, a polycarbonate resin (for example, Iupilon Z300 manufactured by Mitsubishi Gas Chemical) is used as the insulating resin.
A film formed by adding 5 parts by weight of conductive carbon (for example, Ketjen black) to 95 parts by weight was used. The surface was coated with a fluorine resin. The thickness of the film is about 350 μm, and the resistance is about 10 ⁷ to 10 ⁹ Ω · cm. Here, the reason why the intermediate transfer belt 3 is formed by kneading a conductive filler into a polycarbonate resin and forming the film into a film can be used to effectively prevent the intermediate transfer belt 3 from being loosened due to long-term use and accumulation of electric charges. The reason why the surface is coated with the fluororesin is to effectively prevent toner filming on the surface of the intermediate transfer belt due to long-term use.

The intermediate transfer belt 3 is set to a thickness of 100 μm
The first transfer roller 4 formed of an endless belt-shaped film made of semiconductive urethane as a base material and formed around the periphery thereof with a low resistance treatment so as to have a resistance of 10 ⁶ to 10 ⁸ Ω · cm. Is wound around the second transfer roller 5 and the tension roller 6, and is configured to be movable in the direction of the arrow. Here, the peripheral length of the intermediate transfer belt 3 is equal to the longitudinal length (298 mm) of A4 paper, which is the maximum paper size.
The length is set to 360 mm, which is a sum of a length (62 mm) slightly longer than half the circumference of a photosensitive drum (diameter 30 mm) described later.

When the intermediate transfer belt unit 2 is mounted on the printer main body, the first transfer roller 4 is applied to the photosensitive member 11 (shown in FIG. 9) via the intermediate transfer belt 3 by about 9.8.
× 10 ⁴ (N / m ² ), and the second transfer roller 5 is connected to the third transfer roller 12 via the intermediate transfer belt 3 in the same manner as the first transfer roller 4 (see FIG. 9). The third transfer roller 12 is configured to be rotatable following the intermediate transfer belt 3.

The cleaner roller 7 is a roller of a belt cleaner for cleaning the intermediate transfer belt 3. This is a configuration in which an AC voltage for electrostatically attracting toner is applied to a metallic roller. The cleaner roller 7 may be a rubber blade or a conductive fur brush to which a voltage is applied.

In FIG. 8, four fan-shaped image forming units 17Bk, 17Y, 17M, and 17C for each color of black, cyan, magenta, and yellow form an image forming unit group 18 at the center of the printer. Are arranged in an annular shape. Each image forming unit 17Bk, 17Y, 17M,
Reference numeral 17C denotes a printer top plate 1C which is opened about a hinge shaft 1D and is detachable at a predetermined position of the image forming unit group 18. Image forming units 17Bk, 17Y, 17M, 17
C is properly mounted in the printer, so that the mechanical drive system and the electric circuit system on both the image forming unit side and the printer side are connected via a mutual coupling member (not shown), and Electrically integrated.

Image forming unit 1 arranged in an annular shape
7Bk, 17C, 17M, 17Y is a support (not shown)
, Which is driven by a moving motor 19 as a whole, and is fixed and does not rotate.
It is configured to be rotatable around 0. Each image forming unit is rotated by an image forming position 2 facing a second transfer roller 4 that sequentially supports the intermediate transfer belt 3 described above.
1 can be located. The image forming position 21 is the signal light 2
2 is also the exposure position.

Each image forming unit 17Bk, 17C, 17
Since M and 17Y are made of the same components except for the developer put in, the image forming unit 17Bk for black will be described for simplification of description, and the description of the unit for other colors will be omitted.

FIG. 19 shows an image forming unit. Reference numeral 11 denotes a photoreceptor, and 30 denotes a developing roller made of silicone rubber having a JIS-A hardness of 60 ° and having a diameter of 18 mm. The developing roller is pressed against the photoreceptor with a force of 21 N and rotates in the direction of the arrow. 31 is φ14mm
Supplies the toner in the toner hopper to the developing roller. A metal plate 32 forms a toner layer on the developing roller. Reference numeral 33 denotes a power supply to which a DC voltage of 230 V and an AC voltage of 500 pp (1 kHz) are applied. Reference numeral 24 denotes a charging roller having a diameter of 12 mm made of epichlorohydrin rubber and having a DC bias of -1 kV.
Is applied. The photoconductor surface is charged to -450V. 2
6 is a developer reservoir, 34 is a cleaner, 27 is waste toner, 2
8Bk is a black toner.

Reference numeral 35 in FIG. 8 designates a laser beam scanner disposed below the inside of the printer outer casing 1, and includes a semiconductor laser (not shown), a scanner motor 35a, and a polygon mirror 3 (not shown).
5b, a lens system 35c, and the like. The pixel laser signal light 22 corresponding to the time-series electric pixel signal of the image information from the laser beam scanner unit 35 is supplied to an optical path window 36 formed between the image forming units 17Bk and 17Y.
Through a window 37 opened in a part of the shaft 20 to be incident on a fixed mirror 38 in the shaft 20, reflected and reflected by the exposure window 2 of the image forming unit 17 </ b> Bk at the image forming position 21.
5 and enters the image forming unit 17Bk almost horizontally,
Developer reservoir 2 arranged vertically in the image forming unit
The light passes through a passage between the cleaning member 6 and the cleaner 34 and is incident on an exposed portion on the left side surface of the photoreceptor 11, and is scanned and exposed in the generatrix direction.

Since the optical path from the optical path window 36 to the mirror 38 uses the gap between the adjacent image forming units 17Bk and 17Y, the image forming unit group 1
8 has very little wasted space. Also, mirror 3
Since 8 is provided at the center of the image forming unit group 18, it can be constituted by a single fixed mirror, which is simple and easy to align.

Reference numeral 12 denotes a third transfer roller provided inside the printer front plate 1A and above the paper feed roller 39. A nip portion where the intermediate transfer belt 3 and the third transfer roller 12 are pressed against each other is provided. A paper transport path is formed so that paper is fed by a paper feed roller 39 provided below the printer front plate 1A.

Reference numeral 40 denotes a paper feed cassette provided on the lower side of the printer front plate 1A so as to protrude outward, and can set a plurality of papers S at the same time. 41a and 41b are paper conveyance timing rollers, 42a is a fixing roller, 42b is a pressing roller, 42c is a fixing belt made of fluoro rubber, 42d is a heating medium roller, 43 is provided between the third transfer roller 12 and the pair of fixing rollers. The paper guide plates 44a and 44b are paper discharge roller pairs disposed on the paper exit side of the fixing roller pair.

FIG. 10 shows the fixing process. A belt 42c is provided between the fixing roller 42a and the heat roller 42d.
Has been hung. Fixing roller 42a and pressure roller 42
b is applied with a predetermined weight, and a nip is formed between the belt and the pressure roller. Heat roller 42
A heater is provided inside d, and a temperature sensor 51 is disposed on the outer surface.

The pressing roller 42b is pressed against the fixing roller 42a by the pressing spring 52. The recording material 54 having the toner 53 moves along the guide plate 55.

The fixing roller 42a as a fixing member has a rubber hardness (JIS-A) of 20 degrees according to the JIS standard on the surface of an aluminum hollow roller core bar 56 having a length of 250 mm, an outer diameter of 14 mm and a thickness of 1 mm. The elastic layer 57 having a thickness of 3 mm made of silicone rubber is provided. A silicone rubber layer 58 having a thickness of 3 mm is formed thereon, and has an outer diameter of about 20 mm. It rotates at 100 mm / s by receiving a driving force from a driving motor (not shown).

The heat roller 42d has a thickness of 1 mm and an outer diameter of 2 mm.
It consists of a 0 mm aluminum hollow pipe. A 700 W lamp heater 58 for heating was provided inside, and the surface temperature of the fixing roller was controlled to 170 ° C. using a thermistor. When fixing an OHP image, 50 mm / s
And fixing at half speed.

The pressure roller 42b as a pressure member has a length of 250 mm and an outer diameter of 20 mm. It has an outer diameter of 16
mm and a 1 mm thick aluminum hollow roller core 59 made of aluminum have a rubber hardness (JIS
A) is provided with a 2 mm-thick elastic layer 60 made of 55 ° silicone rubber. The pressure roller 42b is rotatably installed, and forms a nip width of 5.0 mm with the fixing roller 1 by a spring-loaded spring 52 on one side 147N.

Each image forming unit 17Bk, 17C, 17
M, 17Y, and the intermediate transfer belt unit 2 are provided with a waste toner reservoir.

Hereinafter, the operation will be described.

First, as shown in FIG. 8, the image forming unit group 18 is moved from the black image forming unit 17Bk to the image forming position 2B.
In one. At this time, the photoconductor 11 is in opposing contact with the first transfer roller 4 via the intermediate transfer belt 3.

In the image forming step, the black signal light is input to the image forming unit 17Bk by the laser beam scanner section 35, and an image is formed with black toner. At this time, the image forming speed of the image forming unit 17Bk (60 mm / s equal to the peripheral speed of the photoconductor) and the moving speed of the intermediate transfer belt 3 are set to be the same.
By the action of the transfer roller 4, the black toner image is transferred to the intermediate transfer belt 3.
Is transferred to At this time, a DC voltage of +1 kV was applied to the first transfer roller. Immediately after all the black toner images have been transferred, the image forming units 17Bk, 17C, 17C
M and 17Y as a whole are driven by a moving motor 19 as an image forming unit group 18 to rotate and move in the direction of the arrow in the drawing, and rotate exactly 90 degrees to stop at a position where the image forming unit 17C reaches the image forming position 21. . During this time, since the portions of the toner hopper 26 and the cleaner 34 other than the photoconductor of the image forming unit are located inside the rotation arc at the tip of the photoconductor 11, the intermediate transfer belt 3 does not contact the image forming unit.

After the image forming unit 17C arrives at the image forming position 21, the laser beam scanner unit 35 inputs the signal light 22 to the image forming unit 17C with a cyan signal and forms a cyan toner image in the same manner as before. Transfer is performed. By this time, the intermediate transfer belt 3 has made one rotation, and the writing timing of the cyan signal light is controlled such that the next cyan toner image is positionally matched with the previously transferred black toner image. During this time, the third transfer roller 12 and the cleaner roller 7 are slightly separated from the intermediate transfer belt 3 so as not to disturb the toner image on the transfer belt.

The same operation as above was performed for magenta and yellow, and a color image was formed on the intermediate transfer belt 3 by superimposing the four color toner images in position. After the transfer of the final yellow toner image, the toner images of the four colors are collectively transferred to the sheet fed from the sheet cassette 40 by the action of the third transfer roller 12 in a timely manner. At this time, the second transfer roller 5 is grounded, and the third transfer roller 12
, A DC voltage of +1.5 kV was applied. The toner image transferred to the paper was fixed by the pair of fixing rollers 42a and 42b. The sheet was then discharged out of the apparatus via a pair of discharge rollers 44a and 44b. The transfer residual toner remaining on the intermediate transfer belt 3 is cleaned by the action of the cleaner roller 7 to prepare for the next image formation.

Next, the operation in the monochrome mode will be described. In the monochrome mode, first, the image forming unit of a predetermined color moves to the image forming position 21. Next, image formation of a predetermined color and transfer to the intermediate transfer belt 3 are performed in the same manner as before, and the transfer is continued as it is after the transfer, to the next sheet transferred from the sheet cassette 40 by the third transfer roller 12. The image was transferred and fixed.

[0270] Table 12 shows the results of image formation using the electrophotographic apparatus of FIG.

[0271]

[Table 12]

When an image was formed using the toner manufactured as described above by using such an electrophotographic apparatus, the solid black image was uniform without any disturbance of horizontal lines, toner splatter, and missing characters. An extremely high-resolution and high-quality image reproducing an image line of / mm was obtained, and a high-density image having an image density of 1.3 or more was obtained. No fogging of the non-image area occurred. Further, even in a long-term durability test of 10,000 sheets, both fluidity and image density showed little change and stable characteristics. In addition, the uniformity of a solid image taken at the time of development was good. There is no development memory. Also, in the transfer, the hollow portion was at a practically acceptable level, and the transfer efficiency was 90%. Further, the filming of the toner on the photoreceptor and the intermediate transfer belt was at a practically acceptable level. Further, the toner is not disturbed at the time of fixing and the toner jumping hardly occurs. But tm7, t
For the toners y7 and tc7, filming of the photoconductor and omission during transfer occurred, and a lot of fog occurred. When the entire solid image was taken at the time of development, blurring occurred in the latter half. At the time of fixing, toner jump occurred.

Next, Table 13 shows the amount of adhering to OHP paper 0.4.
A fixing test of a solid image of g / cm ² or more was performed at 170 ° C. using a fixing device using a belt not coated with oil.
OHP jam did not occur in the fixing nip portion. The offset is 1220 for a solid green image on plain paper.
No occurrence occurred up to the 00th sheet. Even if a silicone or fluorine-based fixing belt was not coated with oil, no surface deterioration phenomenon of the belt was observed, and the effect of adding a fatty acid metal salt was observed. However, in a running test using a toner to which no fatty acid metal salt was added, the surface of the belt deteriorated, and the non-offset property deteriorated.

The transmittance and the offset property at a high temperature were evaluated. The process speed was 50 mm / s, and the transmittance was measured with a spectrophotometer U-3200 (Hitachi, Ltd.) for the transmittance of light at 700 nm. The results of fixability, offset resistance and storage stability are shown.

[0275]

[Table 13]

OHP translucency of 80% or more,
In addition, the non-offset temperature range was 40 to 60K, and a good fixing property was exhibited in a fixing roller using no oil. Aggregation was hardly observed at storage stability at 50 ° C. for 24 hours. However, the toners of tm7, ty7 and tc7 were hardened in the storage stability test, and the non-offset temperature range was narrow.

[0277]

As described above, according to the present invention, a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability and inorganic fine particles B exhibiting negative chargeability are added to the toner matrix exhibiting negative chargeability.
A mechanical and / or thermal surface treatment of a toner matrix to which a fatty acid metal salt is externally attached, and a molecular weight of the kneaded toner. By setting the distribution to a specific distribution form, even when used in a contact type one-component developing method, thermal fusion or aggregation of toner does not occur, image density decreases due to overcharging in long-term continuous use, low temperature and low humidity Fog can be prevented,
It has a uniform charge distribution and can continue to output stable image characteristics even after long-term use.

The electrophotography method using a conductive elastic roller or an intermediate transfer member can prevent dropout or scattering at the time of transfer, and can achieve high transfer efficiency. Filming of the photoreceptor and the intermediate transfer member can be prevented even in long-term use under high humidity. The cleaning property of the intermediate transfer member can be improved. Even when waste toner is recycled, the charge amount and fluidity of the developer do not decrease, there is no agglomeration, the life is extended, recycling development is possible, prevention of global environmental pollution and reuse of resources It can be.

Even if oil is not applied by a silicon or fluorine fixing belt, offset properties can be prevented while maintaining high OHP translucency. In addition, even if the belt is used for a long period of time, good non-offset properties can be maintained without causing a belt surface deterioration phenomenon.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a surface treatment of a toner used in an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing one embodiment of the surface treatment of the toner used in the embodiment of the present invention.

FIG. 3 is a schematic perspective view of a toner melt-kneading process used in an embodiment of the present invention.

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

FIG. 5 is a front view of a toner melt-kneading process used in an embodiment of the present invention.

FIG. 6 is a cross-sectional view of a toner melt-kneading process used in an embodiment of the present invention.

FIG. 7 is a cross-sectional view illustrating a configuration of an electrophotographic apparatus used in an embodiment of the present invention.

FIG. 8 is a cross-sectional view illustrating a configuration of an electrophotographic apparatus used in an embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating a configuration of an intermediate transfer belt unit used in an embodiment of the present invention.

FIG. 10 is a sectional view showing a configuration of a fixing unit used in an embodiment of the present invention.

FIG. 11 is a diagram showing a molecular weight distribution characteristic of a binder resin according to an example of the present invention.

FIG. 12 is a diagram showing a molecular weight distribution characteristic of a toner according to an embodiment of the present invention.

FIG. 13 is a view showing the molecular weight distribution characteristics of a binder resin according to an example of the present invention.

FIG. 14 is a diagram showing a molecular weight distribution characteristic of a toner according to an example of the present invention.

FIG. 15 is a diagram showing the molecular weight distribution characteristics of a binder resin according to an example of the present invention.

FIG. 16 is a diagram showing the molecular weight distribution characteristics of the toner of the example of the present invention.

FIG. 17 is a diagram showing the molecular weight distribution characteristics of the toner according to the example of the present invention.

FIG. 18 is a diagram showing a molecular weight distribution characteristic of the toner according to the embodiment of the present invention.

FIG. 19 is a sectional view showing a configuration of a developing unit used in the embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 2 intermediate transfer belt unit 3 intermediate transfer belt 4 first transfer roller 5 second transfer roller 6 tension roller 11 photoconductor 12 third transfer roller 17Bk, 17C, 17M, 17Y image forming unit 18 image forming unit group 21 image forming position 22 Laser signal light 35 Laser beam scanner unit 38 Mirror 308 Carrier 305 Developing sleeve 306 Doctor blade 307 Magnet roll 314 Cleaning blade 312 Cleaning box 311 Waste toner 313 Waste toner transport pipe 602 Roll (RL1) 603 Roll (RL2) 604 Roll (RL1) Molten film of toner wound on top 605 Heat medium inlet 606 Heat medium outlet

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/01 G03G 15/08 501A 2H077 15/16 103 15/08 501 15/20 101 507 9/08 333 15/16 103 346 15/20 101 381 21/10 15/08 507D 21/00 326 F term (reference) 2H005 AA01 AA06 AA08 AB04 AB09 CA08 CA14 CA25 CA30 CB07 CB13 DA02 DA03 EA01 EA03 EA06 EA07 EA10 2H030 AA07 AB02 AD01 AD03 BB02 BB42 2H032 AA05 BA19 2H033 BA11 BA25 BA26 BB00 BE00 2H034 CB01 2H077 AA37 AC04 AC16 AD06 AD13 AD36 EA14 EA15 FA22

Claims (31)

[Claims] 1. A toner comprising: a toner base having at least a negative electrode chargeability comprising a binder resin and a colorant; and an external additive comprising at least a fatty acid metal salt. 2. A toner comprising a negative electrode chargeable toner base comprising at least a binder resin and a colorant, and an external additive comprising at least a fatty acid metal salt and a positive electrode chargeable inorganic fine particle. toner. 3. A toner matrix comprising at least a binder resin and a colorant and exhibiting negative chargeability, and at least a fatty acid metal salt;
A toner comprising: an external additive composed of inorganic fine particles A having positive chargeability and inorganic fine particles B having negative chargeability. 4. A metal salt of a fatty acid is externally attached to a toner matrix comprising at least a binder resin and a colorant, and a mechanical and / or thermal surface treatment is applied to the toner matrix to which the fatty acid metal salt is externally attached. A toner characterized in that: 5. A method in which a fatty acid metal salt and inorganic fine particles exhibiting positive chargeability are externally attached to a toner matrix comprising at least a binder resin and a colorant, and the fatty acid metal salt and inorganic fine particles exhibiting negative chargeability are externally attached. A toner characterized in that a mechanical and / or thermal surface treatment is applied to the attached toner base. 6. The toner according to claim 4, wherein the surface-treated toner is externally added with inorganic fine particles having positive chargeability. 7. The toner according to claim 4, wherein the surface-treated toner is externally treated with inorganic fine particles A having positive chargeability and inorganic fine particles B having negative chargeability. 8. The toner according to claim 4, wherein the thermal surface treatment is performed by dispersing the toner particles by hot air having a temperature of 50 ° C. or higher with respect to the melting point of the fatty acid metal salt. 9. A mechanical surface treatment comprising a cylindrical rotating body having irregularities on its surface and rotating at a high speed at a peripheral speed of 80 m / sec or more; A fixed body fitted with a narrow gap of 5 mm and having irregularities on the surface, and a toner base to which a fatty acid metal salt is externally attached is air-conveyed to the gap between the rotating body and the fixed body, and a mechanical shock is applied. 6. The toner according to claim 4, wherein the surface treatment is performed by force. 10. The toner according to claim 1, wherein the fatty acid metal salt has a BET specific surface area of 0.1 to 50 m ² / g by nitrogen adsorption. 11. The toner according to claim 1, wherein the fatty acid metal salt has a peak temperature of 100 ° C. to 180 ° C. in a differential scanning calorimetry when the temperature is raised. 12. The toner according to claim ^{2, wherein the} inorganic fine powder A having positive electrode chargeability has a BET specific surface area of 30 to 350 m ² / g by nitrogen adsorption. 13. The ratio of the amount of the inorganic fine powder A exhibiting positive electrode chargeability to the amount of inorganic fine powder B exhibiting negative electrode chargeability is from 50:50 to 9: 9.
8. The toner according to claim 3, wherein the ratio is 5: 5. 14. The inorganic fine powder A exhibiting positive chargeability has a BET specific surface area of 30 to 350 m ² / g due to nitrogen adsorption, and the inorganic fine powder B exhibiting negative chargeability has a BET specific surface area of 5 to 150 m ² due to nitrogen adsorption. 8. The toner according to claim 3, wherein the ratio of the specific surface area of the inorganic fine powder AA to the specific surface area of the inorganic fine powder B is 1: 1 to 70: 1. 15. The toner according to claim 1, wherein the inorganic fine particles are made of one or more of alumina, titania and silica subjected to hydrophobic treatment. 16. The toner according to claim 1, wherein the charge amount of the toner by a suction Faraday cage method is -5 to -45 .mu.C / g. 17. The toner according to claim 1, further comprising a charge controlling agent comprising at least one of a metal salt of salicylic acid, a metal complex of salicylic acid, and an organic boron compound. 18. The binder resin is a polyester resin prepared by polycondensation of an alcohol and an acid, and has at least a succinic acid monomer and a terephthalic acid monomer as an acid component. Acid value is 5-30 KOHmg / g
The toner according to any one of claims 1 to 5, wherein 19. The binder resin is a polyester resin prepared by the condensation polymerization of an alcohol and an acid, and has at least a fumaric acid monomer and a terephthalic acid monomer as an acid component. Acid value is 5-30 KOHmg / g
The toner according to any one of claims 1 to 5, wherein 20. A GPC chromatogram of a toner which has been subjected to mixing and kneading of a toner constituent material comprising a binder resin and a colorant has a molecular weight distribution of 2 × 10 ^{3 to} 3 × 1.
0 at least one molecular weight maximum peak in the ^fourth region, the toner according to any of claims 1 to 5 having at least one molecular weight maximum peak or shoulder in the region of ^{3 × 10 4 ~1 × 10 6} . 21. A toner comprising at least a binder resin and a colorant, wherein the molecular weight distribution of the toner in a GPC chromatogram has at least one maximum molecular weight peak in a region of 2 × 10 ^{3 to} 3 × 10 ^4. 3 × 10 ⁴
It has at least one maximum molecular weight peak or shoulder in the region of 1 × 10 ⁶ , and the height of the maximum molecular weight peak existing in the region of 2 × 10 ^{3 to} 3 × 10 ⁴ is defined as Ha, 3 × 10 ⁴ to
Assuming that the maximum molecular weight peak or shoulder height existing in the 1 × 10 ⁶ region is Hb, Hb / Ha is 0.15 to 0.15.
The toner according to any one of claims 1 to 5, which has a value of 0.90. 22. A toner comprising at least a binder resin and a colorant, wherein the molecular weight distribution of the toner in a GPC chromatogram is at least one molecular maximum peak in a region of 2 × 10 ^{3 to} 3 × 10 ⁴ , 3 × 10 ⁴ -1 × 1
At least one molecular weight maximum peak or shoulder in the region of 0 ^6, in larger area than the molecular weight value corresponding to the maximum peak or shoulder in the molecular weight distribution exists in a molecular weight region of 3 × 10 ⁴ ~1 × 10 ⁶ In the molecular weight curve, assuming that the maximum peak of the molecular weight distribution or the height of the shoulder is 1, the molecular weight corresponding to 90% of the maximum peak of the molecular weight or the height of the shoulder is M90, and 10% of the height of the maximum peak or the shoulder of the molecular weight. When the molecular weight corresponding to is M10, M
The toner according to any one of claims 1 to 5, wherein 10 / M90 is 6 or less. 23. A toner comprising at least a binder resin and a colorant, wherein the molecular weight distribution of the toner in a GPC chromatogram is at least one molecular weight maximum peak in a region of 2 × 10 ^{3 to} 3 × 10 ⁴ , 3 × 10 ⁴ -1 × 1
At least one molecular weight maximum peak or shoulder in the region of 0 ^6, in larger area than the molecular weight value corresponding to the maximum peak or shoulder in the molecular weight distribution exists in a molecular weight region of 3 × 10 ⁴ ~1 × 10 ⁶ In the molecular weight curve, assuming that the maximum peak of the molecular weight distribution or the height of the shoulder is 1, the molecular weight corresponding to 90% of the maximum peak of the molecular weight or the height of the shoulder is M90, and 10% of the height of the maximum peak or the shoulder of the molecular weight. When the molecular weight corresponding to is M10,
(M10-M90) / M90 is 5 or less.
5. The toner according to any one of 5. 24. A waste toner recycling means for recovering the toner remaining on the image carrier after the transfer process into a developing device and reusing it in the developing process.
An electrophotographic apparatus using the toner described in the above. 25. An electrostatic latent image on the image carrier is made visible by inserting a transfer material between the image carrier and the conductive elastic roller and applying a transfer bias voltage to the conductive elastic roller. An electrophotographic apparatus comprising a toner transfer means for transferring an imaged toner, wherein the toner according to any one of claims 1 to 23 is used. 26. A developing roller made of a silicone resin or a urethane resin rotatably supported by a shaft and abutting on an image carrier, supplies the toner by a supply roller made of a urethane resin rotatably supported and abutting on the developing roller. A contact-type non-magnetic one-component means for supplying a developing roller, contacting a doctor blade on the developing roll to form a toner layer, and bringing the developing roller and an image carrier into contact to perform development; Item 14. An electrophotographic apparatus using the toner according to any one of Items 1 to 23. 27. The electrophotographic apparatus according to claim 26, wherein an AC bias is superimposed on a DC bias between the image carrier and the developing roll. 28. A surface of the intermediate transfer member, which is obtained by bringing a toner image obtained by visualizing an electrostatic latent image formed on an image carrier into contact with the surface of an endless intermediate transfer member. A primary transfer process for transferring the toner image to the transfer material is repeatedly performed a plurality of times, and thereafter, the overlap transfer toner image formed on the surface of the intermediate transfer body is collectively transferred onto the transfer material by performing the primary transfer process a plurality of times. An electrophotographic apparatus comprising a transfer system configured to execute a secondary transfer process for transferring, and using the toner according to any one of claims 1 to 23. 29. A plurality of movable image forming members each having at least a rotating image carrier and developing means having toners of different colors, wherein toner images of different colors are formed on the image carrier. An image forming unit, an image forming position composed of a single exposure position and a single transfer position,
An image forming unit group in which the plurality of image forming units are arranged in an annular shape, and each of the plurality of image forming units,
A moving unit for rotating the entire image forming unit group to sequentially move to the single image forming position, an exposure unit for generating a signal light, and the rotation center of the image forming unit group substantially at the center of rotation. 24. The toner according to claim 1, further comprising a color image forming system having a mirror that guides light from an exposure unit to the exposure position, and transferring a toner image of a different color onto a transfer material in a superposed manner. An electrophotographic apparatus characterized by using: 30. Recording of toner using a heat-resistant belt having a heat-resistant and deformable surface layer having a surface layer made of any one of silicone rubber, fluorine rubber and fluorine resin, a fixing roller, a pressure roller and a heating member. 24. An electrophotographic apparatus comprising a fixing system for fixing on a material by the action of heat and pressure, wherein the toner according to claim 1 is used. 31. The electrophotographic apparatus according to claim 30, wherein a heating portion of the heat-resistant belt and a fixing portion for fusing and fixing the toner are different portions.