JPH1195553A - Developer used for developing device and image forming device equipped with the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent image quality from degrading gradually when toner removed by a cleaner is reused as the developer. SOLUTION: A developing device has, in a developing tank 10 for storing the developer, a developing roller 11 opposite a photoreceptor 1 being an image carrier, and develops by carrying developer to a developing area opposite the photoreceptor 1 by means of the developing roller 11. In the developing device, after the latent image on the photoreceptor 1 is developed, it is transferred to paper, the toner remaining on the photoreceptor 1 is removed by the cleaner 7, and the removed toner is recovered as recycled toner into a toner hopper 14 via a connection pipe 18 and carrying means 19 serving as a recovering device. The recovered toner is recycled by controlling so that the developing tank 10 is replenished with it when necessary. In the beginning of image formation, the toner hopper 14 is filled with initial toner. However, when the initial toner is used up, the toner to which an additive different from that added to the initial toner is used for replenishment, thereby compensating the fluidity, electrification performance, etc., of the recycled toner and keeping the image quality almost the same as that obtained in the beginning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for visualizing a latent image provided in an image forming apparatus utilizing an electrophotographic system, for example, a copying machine, a printer, or a facsimile machine. The present invention relates to a developer that contributes to visualization by using a developer and an image forming apparatus that forms an image using the developer.

[0002]

2. Description of the Related Art In an image forming apparatus employing an electrophotographic method, such as a copying machine, a printer, and a facsimile machine, an electrostatic latent image is formed on the surface of a photosensitive member, which is an electrostatic latent image carrier. There is provided a developing device which supplies a developer such as a toner as a colorant to the photoconductor side to make the toner adhere to the photosensitive member in order to visualize the toner image.

The developing device develops the electrostatic latent image formed on the photoreceptor, and the developed toner image is transferred to a transfer material, such as a sheet. And after the transfer,
Part of the toner that has not been transferred remains on the surface of the photoconductor. The remaining unnecessary toner is also removed from the photoreceptor surface in order to repeatedly perform the next image formation. Therefore, a cleaning device that removes the toner remaining on the surface of the photoconductor after the transfer is provided, and the unnecessary toner removed by the cleaning device is stored in a storage unit in the cleaning device.

In the image forming apparatus provided with the developing device as described above, the toner removed by the cleaning device is temporarily stored in a storage portion of the cleaning device, and the unnecessary toner is sent to a collection container. The collection container is discarded and replaced with a new collection container. That is, when the amount of the collected toner exceeds the allowable amount, the collected container is replaced with a new empty collection container, and the collected toner is discarded.

Therefore, it has been considered that the unnecessary toner removed by the above-described cleaning device and collected in the collection container is reused without being discarded.
For example, in Japanese Patent Application Laid-Open No. 60-220380, unnecessary toner is removed by a cleaning device, and the toner is returned to a hopper for supplying toner of a developing device and reused. At this time, the toner returned to the toner hopper is charged to compensate for the insufficient charging at the time of reuse, so that the toner is used for development in the same manner as new toner, and a stable image quality is maintained. .

In Japanese Patent Application Laid-Open No. 6-202373, unnecessary toner removed by a cleaning device is returned to a developing device. By selecting a specific material as an external additive to the toner, it can be reused. The stability of the toner to be used is intended to stabilize the image quality. In other words, in the above-mentioned publication, the external additive added externally is prevented from peeling off or falling off from the toner surface due to the stress applied to the toner during the development. Therefore, as the external additive, inorganic fine particles treated with silicone oil and silicone varnish are used in order to prevent aggregation between toners.

As described above, in order to reuse the unnecessary toner once removed by the cleaning device as a recycled toner, conventionally, the stability of the toner is intended to stabilize the image quality.

[0008]

As described above, the unnecessary toner removed by the cleaning device is reused as a recycled toner without being discarded, so that no waste toner is generated, waste can be reduced, and resources can be saved. This is very advantageous in that it can be handled.

However, even if the external additive on the surface of the toner can be prevented from peeling or separating, the toner recovered through a route of development → cleaning → recovery is subjected to various stresses. Therefore, it is impossible to completely prevent the external additive from being detached or buried in the toner. Therefore, the external additive on the toner surface gradually disappears substantially, and the fluidity and the charging performance deteriorate, and the image quality gradually deteriorates as the number of formed images, particularly the number of times of development, increases.

That is, the so-called recycled toner, which reuses the unnecessary toner removed by the cleaning device, is a mechanical stress in the developing device, and a stress due to collision with a carrier in a two-component developer. In addition, the cleaning device receives a stress when the blade is scraped off, and further receives a mechanical stress and the like during the conveyance along the collection path collected from the cleaning device to the developing device side. Therefore, some of the toner is pulverized by these stresses, and the amount of the fine toner increases.

In addition, not only external additives that affect the fluidity on the toner surface due to these stresses and external additives that affect the polishing performance, but also external additives that are missing or buried on the chargeability of the toner. It happens, and it is difficult to solve this with the current technology.

Therefore, in a two-component developer,
When the above-mentioned recycled toner having reduced fluidity is returned to the developing device and supplied into the developing tank, the amount of toner in the developer, that is, the toner concentration gradually increases, and problems such as image fogging and toner scattering are caused. Occur. Further, there is a problem that a physical attraction force between toners increases, toner aggregation easily occurs, and a black center is generated on an image. In addition, the frequency of contact between the carrier and the toner is reduced, and the toner reaches the developing area with an insufficiently charged state, causing problems such as image fogging and toner scattering.

Further, the above-mentioned recycled toner in which the external additive is missing, buried, or contains a large amount of fine particles has a low fixing strength, and the toner on the transfer material is easily removed, and the image quality cannot be maintained. In addition, the fixing offset performance is deteriorated compared to the initial toner, the toner stain on the fixing roller becomes severe, and in the process of continuing the image formation, the transfer material is gradually stained, and the image quality tends to deteriorate. .

Further, in a developing device using a one-component toner, if the above-mentioned recycled toner in which the external additive is missing, buried, or has an increased amount of fine particles is used, the toner in the developing device is adsorbed to a developing area. The amount of the thin layer of toner on the developing roller to be conveyed is reduced, the developing performance is reduced, and the image density is reduced. Further, there is a problem that the physical attraction force between the toners increases, toner agglomeration or the like occurs, hinders the formation of a thin toner layer on the developing roller, and the image quality deteriorates in which white stripes or the like are partially generated.

The present invention provides an image forming apparatus which can solve the above-mentioned various problems by simple means and can maintain an image quality state in an initial state even when the toner removed by the cleaning device is reused. The purpose is to:

Another object of the present invention is to provide a developer in which the causes of the above-mentioned various problems are eliminated, and by using this developer, deterioration of image quality due to deterioration of development and fixability can be prevented. Another object of the present invention is to provide a developing agent.

Accordingly, an object of the present invention is to provide a developer which is disadvantageous in using a recycled toner, and in particular, a developer which always has good charging performance and fluidity.

[0018]

According to the present invention, there is provided an image forming apparatus comprising a developing roller having a developing roller for conveying a developer containing toner to a developing area facing an image carrier. With the device, after transferring the image formed by developing the latent image formed on the image carrier with a developer,
In the image forming apparatus, the toner remaining on the image carrier is removed by a clowning device, and the removed toner is recovered to the developing device via a recovery device and reused as recycled toner. The initial developer charged at the initial stage of development and the replenishment developer newly replenished with respect to the initial developer are added to an external additive different from at least the external additive externally added to the toner of the initial developer. Wherein the replenished developer is replaced with the initial developer and replenished, and reused together with the removed toner.

For this purpose, the toner constituting the replenishment developer is treated with an external additive having a larger amount than the external additive of the toner of the initial developer or with a different external additive. . As a result, when the toner removed by the cleaning device is reused as recycled toner,
Since the amount of the external additive added to the toner of the initial developer is large, the external additive sufficiently compensates for the fluidity and the charging performance. A constant state can be maintained when used. Further, by further adding a material different from the external additive of the initial developer as an external additive, the deterioration of the image quality due to disappearance or burial of the external additive of the toner to be reused as described above is compensated for. Therefore, a stable image quality state can always be maintained.

Further, the developer used in the developing device for achieving the object of the present invention develops the latent image formed on the image carrier by supplying a developer containing toner, and transfers the developed image to a transfer material. After the transfer, the toner remaining on the image carrier is removed, and the removed toner is reused as recycled toner. A developer and a replenishment developer replenished after use of the initial developer, wherein an external additive added to the toner of the replenishment developer is an external additive added to the toner of the initial developer. A developer used in a developing device, wherein the amount or type of the developer is different.

Therefore, the external additive to be added to the toner is selected from materials which affect the fluidity or charging performance of the toner or the polishing of the image bearing member. The harmful effects that the original function of the external additive cannot be sufficiently exhibited due to the disappearance or burial of the developer can be sufficiently compensated for by the replenishment developer. As a result, the image quality state before the toner removed by the initial cleaning device is collected and reused, and the image quality state when the toner is collected and developed can be maintained substantially constant.

For example, by increasing the amount of the external additive of the replenishment developer, the external additive can be sufficiently supplemented to the collected toner, and the image quality can be kept constant. At this time, as the external additive, there are a material contributing to the fluidity, a material contributing to the charging performance, a material for polishing the image carrier, preventing image blur, and stabilizing the image quality, and the like. , Or a combination of a plurality of them, and by increasing the amount or changing the type, deterioration of image quality can be prevented.

Further, the developer used in the developing device for achieving the above object of the present invention develops the latent image formed on the image carrier by supplying a developer containing a toner, and develops the image. Is transferred to a transfer material, and the toner remaining on the image carrier is removed, and the removed toner is initially charged into the developing device and used when the removed toner is reused as recycled toner. Initial developer,
A replenishment developer replenished after use of the initial developer, wherein the glass transition point and the toner melt viscosity of the binder resin constituting the toner of the replenishment developer are different from those of the toner of the initial developer. I do.

This makes it possible to improve the fixing property and prevent the fixing offset, thereby preventing the image quality from deteriorating. In other words, the recycled toner receives stress, loses or buries the external additive, and is further pulverized into a fine powder toner, so that the fixability cannot be improved. In order to compensate for this, a sufficient fixing property can be maintained by using a developer that improves the fixing property as a replenisher, thereby preventing the image quality from lowering.

Further, the developer used in another developing device for achieving the object of the present invention described above develops the latent image formed on the image carrier by supplying a developer containing toner and developing the latent image. After the image is transferred to the transfer material, the developer remaining in the image carrier is removed, and the developer is initially charged into the developing device in a developing device in which the removed toner is reused as recycled toner. And a replenishment developer replenished after the use of the initial developer, wherein the amount of the anti-adhesive agent constituting the toner of the replenishment developer is such that the adhesion of the toner of the initial developer is reduced. It is characterized by being different from the amount of the inhibitor.

This uses a replenishing developer in which the amount of an anti-adhesive agent constituting the toner is increased, for example, so as to prevent the toner from adhering to the fixing device. As a result, it is possible to prevent a fixing offset such that the toner adheres to the fixing device side and is transferred to the sheet again when the fixing process is performed after the development is performed using the recycled toner. That is, it is possible to prevent a large amount of the anti-adhesive agent from being attached to the fixing device.

Therefore, even when the developer used in the above-mentioned developing device is composed of a one-component toner, the fluidity and the charging performance deteriorate when collected as recycled toner. It can be supplemented with a replenishment developer, that is, a replenishment toner, and similarly, image quality degradation can be suppressed. The use of the one-component toner eliminates the need for a carrier or the like, so that only the replenishment toner needs to be constantly added until the life of the developing device reaches its end. Become.

As described above, even if the toner removed by the cleaning device is reused, the image quality can be prevented from deteriorating, and it is only necessary to additionally supply a replenishing developer. Therefore, the apparatus can be simplified, and the burden on the user and the maintenance can be reduced.

[0029]

Embodiments of the present invention will be described below in detail with reference to the drawings. The image forming apparatus of the present invention,
An embodiment of a developer used in a developing device provided in the image forming apparatus will be described with reference to FIG.
In particular, in the image forming apparatus of the present invention, unnecessary toner is removed by a cleaning device, and the toner is collected in a developing device so as to be reused as a recycled toner, so as to contribute to development again. .

First, referring to FIG. 1, an image forming apparatus provided with a developing device capable of using recycled toner according to the present invention will be described.

In the image forming apparatus, a process means for forming a plurality of images is arranged around a drum-shaped photosensitive member 1 which is an image carrier which is driven to rotate at a constant speed in the direction of an arrow at a substantially central portion. I have. This image forming process means
First, a charger 2 for uniformly charging the surface of the photoconductor 1, a light image from an optical system for irradiating an image with light corresponding to an image (not shown), and a light image formed by irradiating the optical image with the above optical system A developing device 4 according to the present invention for visualizing the developed electrostatic latent image, and a transfer device 5 for transferring the developed image (toner image) to a sheet, which is a sheet-like transfer agent, which is appropriately conveyed A peeling charger 6 for peeling the transferred paper from the photoconductor 1, a cleaning device 7 for removing a residual developer (toner) not transferred to the surface of the photoconductor 1 after the transfer, and a charging remaining on the surface of the photoconductor 1. A static eliminator 8 for removing charges is arranged in this order in the rotation direction of the photoconductor 1.

Although not shown, for example, a large number of sheets are stored in a tray or a cassette. One sheet of the stored sheets is fed by feeding means, and the above-described transfer device 5 is disposed. The photoconductor 1 is transferred to a transfer area facing the photoconductor 1.
The toner is fed so as to coincide with the front end of the toner image formed on the surface. The sheet after the transfer is charged by the peeling charger 6.
It is peeled off from the photoreceptor 1 and sent to a fixing device (not shown).

The fixing device fixes the unfixed toner image transferred onto the paper as a permanent image,
A surface facing the toner image is formed of a heat roller heated to a temperature at which the toner is melted and fixed, and a pressure roller or the like is provided which is pressed against the heat roller and closely adheres the paper to the heat roller side. Make up. The sheet that has passed through the fixing device is discharged to the outside of the image forming apparatus via a discharge roller (not shown).

An optical system for irradiating the light image 3 onto the surface of the photoreceptor 1 irradiates a document placed on a document table with a copying machine, and reflects light reflected from the document on a mirror and a mirror. An image is formed via an image lens. When the image forming apparatus is a printer or a facsimile apparatus, the optical system transmits a light beam from a semiconductor laser that is ON-OFF controlled in accordance with input image data through a polarizer or the like. It is configured to irradiate the photoreceptor 1.
With this optical system, the reflected light image 3 of the document is directly radiated onto the photosensitive member 1 or the light image 3 corresponding to the image data is formed on the photosensitive member 1 to form an electrostatic latent image on the uniformly charged surface of the photosensitive member 1. Like that.

The electrostatic latent image formed on the surface of the photoconductor 1 in this manner is developed by the developing device 4 arranged so as to face the photoconductor 1 in FIG. That is, the toner as the developer is selectively adhered as an electrostatic latent image and is visualized with the toner.

The developing device 4 includes a developing roller 11 rotatably in a developing tank 10 containing the developer 9 and a stirring and conveying means 12 for conveying or (and) stirring the developer. A toner replenishing device 13 for replenishing toner as needed is provided.

The developing roller 11 is, for example, a two-component developer,
Alternatively, if a one-component toner having magnetism is used, a magnetic roller including a large number of magnetic poles is provided in a cylindrical non-magnetic sleeve, and the sleeve is driven to rotate in the direction of the arrow, The developer is attracted by the magnetic force of the magnet roll, and is conveyed to a developing area facing the photoconductor 1. Therefore, the developer 9 is attracted onto the sleeve by the magnetic force of the magnet roll, transported by the rotation of the sleeve, and transported to the developing area facing the photoconductor 1. Then, at the position of one magnetic pole of the magnet roll facing the developing area, the developer brushes like a brush, which rubs against the surface of the photoreceptor 1 and forms a toner on the electrostatic latent image formed on the surface of the photoreceptor 1. Adheres and develops.

The developer 9 is, for example, a two-component developer composed of a toner and a magnetic carrier, a one-component developer having a magnetic property of the toner itself, and a developer composed of a non-magnetic one-component toner. Is known.

Although not shown in FIG. 1, the developer adsorbed on the developing roller has a regulating member (doctor) so that the amount of the adsorbed developer becomes constant before being conveyed to the developer position. Is partially removed. In other words, one end of the regulating member is fixed to the developing tank 10 and the other end of the regulating member is arranged with a fixed gap (interval) from the developing roller 11, so that the amount of the developer passing through the regulating member is regulated to a fixed amount. A thin layer of the developer 9 is formed on the surface of the developing roller 11 and is conveyed to the developing area.

The toner replenishing device 13 has a replenishing roller 15 for replenishing toner as a developer in a hopper 14 for storing toner. The replenishing roller 15 is made of, for example, a porous member (for example, sponge), and holds the toner in a porous portion to replenish the toner through a replenishing port formed in the developing tank 10.

The developing tank 10 described above faces the supply port.
A stirring and conveying means 12 is arranged on the side, and the supplied toner is stirred with the developer 9 in the developing tank 10 and supplied to the developing roller 11.

As described above, the developer 9 is a two-component system composed of a carrier and a toner, and a one-component system composed of only a toner.
In addition to one-component systems, there are non-magnetic one-component systems. In the case of a non-magnetic one-component toner, the toner cannot be attracted to the surface of the developing roller 11 by a magnetic force. As the developing roller 11 in this case,
A member such as rubber is often used. Then, the toner layer adsorbed on the surface of the developing roller 11 by a regulating member (not shown) is made to be a constant thin layer.

In the case of the developer 9 made of a one-component toner, since there is no need to control the toner concentration in the developer, the toner supply device 13 is not provided, and the developer tank 10 is connected to the developing tank 10 via a toner cartridge or the like. It is configured to be replenished once. When it is necessary to replenish the developing tank 10 with a certain amount of one-component toner, the toner in the toner cartridge is replenished to the toner replenishing device 13 at one time. The toner will be supplied accordingly.

According to the above configuration, the developer 9 in the developing tank 10 is sufficiently agitated by the agitating / conveying means 12, and the developer is charged to a predetermined polarity, for example, positive. The charged developer is supplied to the developing roller 11 and the developing roller 1
For example, it is magnetically attracted to the recording medium 1 and transported to the developing area.

Then, the remaining developer which has not contributed to the development after the development is returned into the developing tank 10, is scraped off from the developing roller 11, is agitated by the agitating / conveying means 12, and is again supplied to the developing. Is circulated and supplied.

Hereinafter, an example of an image forming apparatus in which the toner removed by the cleaning device 7 according to the present invention is reused as a recycled toner, and an example of a developer used in a developing device will be sequentially described.

(First Embodiment) FIG. 1 shows an image forming apparatus for making recycled toner usable according to the present invention.
As shown in (1), the toner remaining on the surface of the photoreceptor 1 after the transfer is removed by the cleaning device 7, and the removed toner is collected in the developing device 4, especially in the hopper 14 of the toner replenishing device 13, and the collected toner is collected. The toner is configured to be reused.

That is, as shown in the drawing, the cleaning device 7 is provided with a cleaning blade 16 whose tip contacts the surface of the photoconductor 1 with an appropriate pressure and scrapes off the toner on the surface of the photoconductor 1. The toner 17 removed by the above is temporarily stored in the container 17 of the cleaning device 7. The housing 17 of the cleaning device 7
Is provided with, for example, a screw-shaped conveying means (not shown) for conveying the removed toner 18 in one direction.

One end of the cleaning device 7 is provided with a toner hopper 14 on the toner replenishing device 13 side of the developing device 4.
Connecting pipe 19 forming a toner conveying path communicated with
A screw-shaped conveying means 20 for collecting the toner 18 to the toner hopper 14 is provided in the connecting pipe 19.

The transport means provided in the cleaning device 7 for transporting the removed toner 18 (not shown) to the connecting pipe 19 and the connecting pipe 19 are provided in such a relationship that the toner 18 is sent to the connecting pipe 19. The cleaned toner 18 is collected in the toner hopper 14 of the toner supply device 13.

The toner hopper 13 is replenished with new toner 21 for replenishing toner into the developing tank 10 in advance.
8 are mixed and supplied to the developing tank 10 when necessary.

The toner is supplied from the toner replenishing device 13 into the developing tank 10 by a toner concentration sensor (not shown).
0, and toner supply is performed when the toner density sensor detects that the toner density is insufficient.
That is, the supply roller 15 is rotated, and the toner held by the supply roller 15 is supplied into the developing tank 10. At this time, the toner 18 collected in the toner hopper 14 together with the new toner 21, that is, the recycled toner may be supplied at the same time.

With the above configuration, the toner 18 removed by the cleaning device 7 is transported from the cleaning device 7 by the connecting pipe 19 by the transporting means 20 as a recovery device, and is recovered to the toner hopper 14. This toner 1
8 is supplied together with new toner 21 to the developing tank 10 by the toner replenishing device 13 as a recycled toner, and contributes again to the development via the developing roller 11. Therefore, the unnecessary toner removed by the cleaning device 7 is reused, and it is not necessary to dispose of the removed toner and to provide a container for collecting the discarded toner.

At this time, in the present invention, when the image forming apparatus is newly arranged, when the developing device 4 is newly replaced, or when the developer 9 in the developing tank 10 of the developing device 4 is replaced.
Is replaced with a new developer, the developer used in the initial development by the developing device 4, for example, in the case of a two-component developer, the initial toner and the initial toner in the toner hopper 14 are lost, and additional replenishment is performed. In the replenishment toner at the time, the amount of the external additive by the new toner or the material of the external additive is different. For example,
The external additive is made different between the initial toner and the replenished toner that is newly replenished after the initial toner has run out.

Accordingly, in the image forming apparatus, the toner hopper 14 is filled with the initial toner when the electrostatic latent image on the photosensitive member 1 is developed by the developing device 4 for the first time, and the development is performed with the initial toner. Thus, the initial toner in the toner hopper 14 gradually decreases. Then, when the amount of toner in the toner hopper 14 becomes equal to or less than a predetermined amount, the image forming apparatus notifies the user or the like to newly fill the toner.

Thus, the user newly replenishes the toner into the toner hopper 14. At this time, the replenishment toner differs in the amount and material of the external additive added to the above-described initial toner. That is, an external additive is added to the toner in order to improve fluidity and chargeability.

For example, by setting the amount of the external additive of the new toner to be replenished to the toner hopper 14 larger than the amount of the external additive of the initial toner, the toner is removed by the cleaning device 7 and the toner hopper is recycled. Even when the toner 18 collected and reused by the toner 14 is subjected to stress, since many external additives are externally added to the replenishment toner, the surface of the toner recovered and reused by the external additive is large. In addition, an external additive is sufficiently added, and it is possible to suppress deterioration of image quality due to poor fluidity and charging performance.

The material of the external additive is different between the new toner and the replenishment toner. For example, by adding an external additive of a different material that is not externally added to the external additive of the initial toner to the replenishment toner, the external additive is sufficiently added to the collected and recycled toner as described above, Deterioration of chargeability and fluidity can be prevented. As a result, even if the toner 18 removed by the cleaning device 7 is reused for development again, it is possible to prevent the image quality from being greatly deteriorated.

Examples of the external additives externally added to the toner include silica, titanium oxide, zinc oxide and the like which improve the fluidity of the toner and prevent aggregation of the toner. Examples of the external additives that affect the charging performance include imidazole dielectrics and hydrosaltite compounds.

Further, as an external additive, there is magnetite or the like as a material which affects the polishing of the surface of the photoreceptor 1.
In this method, the surface of the photoconductor 1 is polished in order to eliminate the deterioration of the image quality when toner adheres or is oxidized on the surface of the photoconductor 1, in particular, the image blur.

Therefore, when silica is added as an external additive of the initial toner, the amount of silica is increased, or zinc oxide or hydrosaltite compound is added in addition to silica. I do. The external additive may be used alone or in combination of two or more, and may be set as needed.

Examples are shown below to confirm the effect of the present invention that the above-described deterioration in image quality does not occur.

(Embodiment 1) In an image forming apparatus, a general electrophotographic type shown in FIG.
As the developing device 4, a magnetic brush developing method was used to develop the electrostatic latent image formed on the photoreceptor 1. In this case, the photoconductor 1 used was an OPC photoconductor composed of an organic photoconductive layer. Then, the cleaning blade 1 is cleaned by the cleaning device 7.
6, the unnecessary toner was removed, and was collected in the toner hopper 14 of the developing device 4 by the collecting device (19, 20), and the toner was reused.

Therefore, the composition of the toner contained in the developing tank 10 of the developing device 4 before adding the external additive of the developer is 90 parts by weight of polystyrene as a binder resin and carbon black as a colorant. , 5 parts by weight of a charge controlling agent, and 3 parts by weight of a polyethylene wax as an antiblocking agent are sufficiently stirred and mixed with a mixer, and the mixture is kneaded with a screw extruder under heating.
The kneaded product was cooled and then coarsely pulverized. The coarsely pulverized product was finely pulverized by a jet pulverizer, and the finely pulverized product was subjected to a classification treatment to obtain a toner having an average particle diameter of about 9 μm before external addition.

The binder resin constituting the toner is not limited to those described above, but may be any of styrene-based copolymers such as styrene-butadiene copolymer and styrene-acrylic copolymer, polyethylene and polyethylene vinyl acetate. Polymers, ethylene polymers such as polyethylene vinyl alcohol copolymers, phenolic resins, epoxy resins,
Allyl phthalate resin, polyamide resin, polyester resin and maleic acid resin can be used.

Examples of the coloring agent other than carbon black include, for example, nigrosine dye, aniline blue, chalco oil blue, chrome yellow, ultramarine yellow, methylene blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, and malachite green. , Oxalate, Lamp Black, Rosebergal, and mixtures thereof can be used.

Further, as charge control agents, amino compounds, quaternary ammonium compounds and organic dyes, particularly basic dyes and salts thereof, are known. Benzyldimethyl-hexadecylammonium chloride, decyl-trimethylammonium chloride, Nigrosine base, nigrosine hydrochloride, safranin, crystal violet, and the like can be used.

As an anti-adhesive agent, polypropylene wax, paraffin wax, or the like can be used in addition to polyethylene wax, and this is extremely effective in improving the releasability of the toner from a fixing device (fixing roller). I do.

On the other hand, the above-prepared toner was mixed with various external additives shown in Table 1 below by stirring with a mixer to perform external addition processing. The amount of the external additive depends on the toner 10 before the external additive.
The ratio to 0 parts by weight was shown.

[0070]

[Table 1]

Therefore, in Table 1 described above, No. 1 was used as the initial toner after the external addition. No. 1 toner was used. No. 1 is used as a replenishing toner to be replenished after consumption. 2-No. The toner of No. 7 was used, and while the toner removed by the cleaning device 7 was reused, 40,000 copies, that is, development was performed for each. The toner image after development was transferred to paper and the image state after fixing was confirmed. The results are shown in Table 2 below.

Here, for comparison, toner No. No. 1 as the initial toner, and the replenishment toner as the same No. as the initial toner. 1 is referred to as REF. The results indicated as “.” Are additionally shown.

[0073]

[Table 2]

In Table 2, fog was evaluated by making a white copy of white paper to evaluate the density of the paper before the copy and the density of the discharged paper based on the difference between the values measured by a whiteness meter. That is, as the numerical value increases, the fog increases. Also,
The toner scattering refers to the amount of toner accumulated in the lower part of the developing device 4. Further, for image blur, a line image was formed and evaluated visually. At this time, for copying, an image was formed by facilitating a test chart having a white portion and a line portion.

As can be seen from Table 2, the toner No.
No. 1 as the replenishing toner instead of No. 1. 2-No. When the toner No. 6 was used, the fogging of the image was reduced, and the scattering of the toner was also reduced. Further, the replenishment toner was designated as No. 7
By using this, an image could be obtained with good character reproducibility without image blur.

Therefore, by increasing the amount of the external additive, particularly the amount of silica, like the initial toner (No. 1) and the replenishment toner (No. 2), the toner 18 removed by the cleaning device 7 can be removed. Even when used as a recycled toner, it was possible to obtain an image with good and stable image quality without increasing fog and causing image quality deterioration.

Further, like the initial toner (toner No. 1) and the replenishment toner (toners No. 3 to No. 6), the material of the external additive is changed, that is, the external additive is different from the external additive of the initial toner. Almost the same effect as that obtained by changing the amount as described above could be obtained by further adding the additive.

Further, as in the case of the initial toner (No. 1) and the replenishment toner (No. 7), by increasing the amount of the external additive, particularly magnetite, it is possible to maintain a good image quality without image blur. Was.

On the other hand, as in the case of the initial toner (No. 1) and the replenishment toner (No. 1), the replenishment toner is used in exactly the same amount and with the same material as the external additive of the initial toner, thereby gradually becoming Fog increases, and the amount of toner scattering also increases. Then, image blurring occurred, and stable image quality could not be obtained.

When the toner 18 removed by the cleaning device 7 is used as a recycled toner, the fluidity is deteriorated due to the missing or buried external additives which affect the fluidity of the toner surface. In the above, if the toner 18 is continuously used, if the toner density control is performed using the magnetic permeability sensor for detecting the toner density, the toner density will increase, causing image fogging and toner scattering. As shown in FIG. The result shown in FIG.

On the other hand, by making the amount of silica as an external additive larger than that of the initial toner as a supplementary toner,
Even when the removed toner 18 is reused, the fluidity is supplemented. As shown in FIG. 2, fogging of the image can be prevented, so that the image quality can be stabilized. In addition, the same amount of silica and magnetite as external additives was used. The same effect can be obtained when 3 and 4 are used as supplementary toners. In this case, a stable image quality was obtained by maintaining the charge amount and the like at a predetermined value even under environmental changes, particularly under an environment such as high temperature and high humidity.

Further, as an external additive affecting the chargeability of the toner, a toner No. 1 containing an imidazole dielectric and an alkamizer separately was added. It was particularly effective when 5 and 6 were used as replenishment toners.

On the other hand, in order to maintain good image quality,
The surface is polished so as to be always in a good state. For that purpose, magnetite is more often used as an external additive to be added to the toner. Using the magnetite as toner N
o. As shown in FIG. 7, a larger amount is added than the amount of the initial toner. This makes it possible to compensate for a decrease in the polishing effect of the photoconductor 1 when the recycled toner is used, and to maintain a good image quality. In particular, the above-described magnetite is used as an external additive to remove nitrogen oxides generated in the charger 2 and the transfer device 5 on the photoreceptor 1 and to remove the nitrogen oxides. By increasing the amount of magnetite,
The polishing effect was maintained, thereby preventing deterioration of image quality, particularly image blur, etc., and as shown in Table 2, a good image quality without image blur could be maintained. Particularly, as the photoconductor 1, O
The effect becomes remarkable in the PC photoreceptor.

(Second Embodiment) In the embodiment described above, the fluidity and charging performance of the toner are kept good,
By increasing the amount of the external additive or by using a different material as an external additive for performing stable development, a stable image quality can be obtained even when the toner 18 removed by the cleaning device 7 is reused as a recycled toner. It can be maintained.

In the second embodiment, the initial toner and the replenishment toner are different from each other, and the image quality is prevented from deteriorating by stabilizing the fixability. That is, the material for the fixing property is made different between the initial toner and the replenishment toner so that a good image quality state is maintained.

Toner 1 removed by cleaning device 7
When the recycled toner 8 is used as the recycled toner, the fixing property is deteriorated due to the strays received by the recycled toner, and the toner adheres to a fixing roller (heat roller or the like) as a fixing device, causing an offset phenomenon such that the toner is transferred to paper. Image quality may be degraded. In addition, the fixability deteriorates, the image after fixing is peeled off, the image is disturbed, and the user's hand may be stained.

That is, the recycled toner is subjected to various stresses, so that the external additives disappear and the fine powder toner increases. As a result, the fixing strength and the fixing offset to the paper are generated,
The image on the surface of the sheet, that is, the toner image is easily peeled off, and at the same time, the sheet is stained by the offset phenomenon, and the image quality is deteriorated.

In order to solve these problems, in this embodiment, the initial toner initially filled in the toner hopper 14 disappears and the replenishment of newly replenished toner improves the fixability, thereby causing a fixing offset. Toner with no properties. Therefore, as replenishment toner,
A glass transition point and a melt viscosity of the toner which are shifted in a direction to improve the fixing strength are used.

Thus, when the finely pulverized toner in the recycled toner is collected by the toner hopper 14 and contributed to the development, the fixability and the like are deteriorated, and the deterioration of the image quality can be prevented.

As described above, as a method of changing the glass transition point of the toner, the molecular weight distribution of the binder resin and the like constituting the toner is changed. For example, by lowering the molecular weight of one binder resin of the composition constituting the toner, the glass transition point is lowered, and the melting temperature is lowered, so that the fixing strength to paper is increased.

Therefore, a binder resin having a different molecular weight between the initial toner and the replenishment toner may be selected and used. Further, as a method of making the molecular weight different, the method can be easily performed in the process of manufacturing the toner without selecting a material having a different molecular weight in advance. For example, the conditions are changed in the kneading process when manufacturing the toner. For example, the temperature and the extrusion speed are changed. For example, when the material is kneaded in a state in which stress is applied to the material by lowering the kneading temperature, the molecules are cut, and the state shifts to a low molecular weight state.

Further, in order to suppress the fixing offset phenomenon in which the toner adheres to the fixing roller and the like constituting the fixing device and is re-transferred to the sheet, the amount of the wax which is an anti-adhesive agent is changed. That is, the wax amount of the replenishment toner is increased relative to the initial toner. Thus, even when the recycled toner is collected as fine powder toner, adhesion of the toner to the fixing roller can be suppressed, and deterioration in image quality due to fixing offset can be prevented.

As described above, the glass transition point and the toner melting viscosity of the initial toner and the replenishment toner are shifted in the direction of improving the fixing strength. That is, the temperature of the glass transition point of the replenishment toner is set lower than the temperature of the glass transition point of the initial toner. Further, by changing the molecular weight, the melt viscosity of the toner is shifted in a direction for improving the fixing strength, thereby improving the fixing strength.

An example will be described below to confirm the above effect, that is, the effect of preventing the deterioration of image quality due to the deterioration of fixability when the toner after cleaning is reused as recycled toner.

(Embodiment 2) As an image forming apparatus, FIG.
The two-component developer was used as the developer to be used. This is the same as that described in the above (Example 1).

Next, the toner used in this embodiment will be described.

The composition of the toner was 90 parts by weight of polystyrene as a binder resin, 5 parts by weight of carbon black as a coloring agent, 2 parts by weight of a charge control agent, and 3 parts by weight of polyethylene wax as an anti-adhesive agent. Parts or 5 parts by weight is sufficiently stirred and mixed with a mixer, and the mixture is kneaded with a screw extruder under heating. After cooling the kneaded material, it is coarsely pulverized, the coarsely pulverized material is finely pulverized by a jet pulverizer, and the finely pulverized material is subjected to classification treatment to have an average particle size of about 9 μm.
A small amount of toner before external addition was manufactured.

Toner 1 before addition obtained as described above
External additives of 0.3 parts by weight of silica and 0.2 parts by weight of magnetite were stirred and mixed with a mixer with respect to 00 parts by weight, and subjected to an external addition treatment. Further, the physical properties of the used toner and the amount of wax which is an anti-adhesive agent are as shown in Table 3 below. In this case, various molecular weights of polyethylene as a binder resin constituting the toner were selected and used.

Here, the toner No. 8 and toner no. 9
Are different from each other in the molecular weight distribution of the binder resin.
That is, the toner No. The number average molecular weight (M
n) was lowered, so that the temperature at the glass transition point was set low. Further, the toner No. 10, the weight average molecular weight (Mw) of the distribution amount of the binder resin was increased. The amount of washes constituting No. 11 The amount was larger than the wax amount of the toner No. 10.

[0100]

[Table 3]

In Table 3, the toner No. 8 as an initial toner, and after the initial toner is exhausted,
The toner to be replenished is designated as toner No. 8 was used as a comparative example (REF.), And the other toner N
o. Table 9 below shows the results of forming 40,000 sheets of images, particularly developing (copying) each using toners 9 to 11 as replenishing toners and reusing toner removed by the cleaning device 7 as recycled toners. The results are shown in FIG.

[0102]

[Table 4]

In Table 4, dirt on the fixing roller was evaluated based on the difference between the values measured by a whiteness meter before and after passing white paper through the fixing roller. In this case, in the image formation, the image formation was performed using a test chart including images of white portions, characters, and other images. Here, it is shown that the larger the numerical value, the more severe the fouling of the fixing roller.

From the results shown in Table 4, the fixing roller was found to have the toner No. When the toner No. 8 was used as the initial toner and the replenishment toner after the initial toner was exhausted, the toner was extremely stained. In this regard, when the initial toner and the replenishment toner are different, the fouling of the fixing roller is reduced,
Further, the toner No. As shown in FIG. 11, by using a toner having a large amount of wax as a replenishing toner, the effect of reducing stains on the fixing roller is enhanced.

Further, as a result of confirming the fixing performance, in particular, the initial toner 8, and the toner to be replenished thereafter is the toner No. REF. And toner N
o. FIG. 2 shows the results of using the toner 9 or 10. In FIG. 2, in order to confirm the fixing strength, the portion where the halftone image was formed was evaluated by the ratio of the density after rubbing with the eraser to the density before rubbing. The density at this time is a value measured by a Macbeth densitometer. In FIG. 2, the higher the value, the higher the density (I) before and after rubbing with the eraser.
D) No difference, indicating good fixing strength.

As can be understood from this figure, since the fixing strength is set to be higher so that the molecular weights of the binder resin of the initial toner and the replenishment toner can be made different, the deterioration of the image quality due to defective fixing or the like is also eliminated. Was done.

Therefore, the contamination of the fixing roller can be reduced by making the initial toner and the replenishment toner different from each other, so that the deterioration of the image quality due to the fixing offset can be prevented. At this time, the wax amount of the initial toner and the replenishment toner are made different from each other, and the wax amount of the replenishment toner is made larger.

Here, from the initial state, the toner Nos. If toners such as 9, 10, and 11 are used, problems occur in fixing in an initial state. That is, initially, the toner removed by the cleaning device 7 is not collected on the developing device 4 side, so that the toner that has not been initially stressed adheres to the fixing roller, causing an offset phenomenon, This also stains the fixing roller.

For this reason, as shown in Table 3, the initial toner and the replenishment toner are used separately.
And a good result as shown in FIG. 2 can be obtained.

(Third Embodiment) In the above-described developing device, a two-component type developer, that is, a developer composed of a carrier and a toner is used, and the toner removed by the cleaning device 7 is used as the developing device. Is collected in the toner hopper 14 and reused.

In this embodiment, a developing device using a one-component toner instead of a two-component developer will be described. Also in this one-component toner,
The same as the two-component developer, the cleaning device 7
After the transfer, the toner remains on the photoreceptor 1 and the toner is removed and reused.

In the case of the one-component toner, the developing device 4
When it is sent back to the side and reused, it is subjected to stress similarly to the above-described two-component type developer, particularly the toner, and if the image is continuously formed as it is, the image quality gradually decreases. .

Therefore, even in a one-component toner,
Similarly to the above, the initial toner and the replenishment toner are not completely the same, and the amount of the external additive added to the members related to the fluidity and the charging performance, particularly the toner, By changing, the defect of the recycled toner is sufficiently compensated for and a constant image quality is maintained.

In FIG. 1, when a one-component toner is used, particularly in the case of a non-magnetic one-component toner, the developing roller 11 is, for example, a rubber roller, and a thin layer of toner is formed on the roller surface. For this purpose, a blade (applying means or the like) that is pressed against the surface of the roller 11 is provided. The toner, which is a developer, is transported to a developing area facing the photoreceptor 1, and selectively adheres to the electrostatic latent image, and the other toner that cannot contribute to the development is returned to the developing tank 10. Is removed from the surface of the developing roller 11 and is again applied to the surface of the developing roller 1 via the above-described blade.

At this time, the toner adhering to the electrostatic latent image formed on the surface of the photoreceptor 1 is transferred to the paper by the transfer unit 5, while the untransferred toner is transferred to the crew of the clogging device 7. The toner is removed by the cleaning blade 16, and the removed toner is collected toward the developing device 4 by a collecting device including the connecting pipe 19 and the conveying unit 20. This collected toner is collected in the toner hopper 14 if a two-component developer is used. However, in the case of a one-component system, it is not necessary to control the mixing ratio with the carrier. 4 is collected in the developing tank 10.

As described above, even in the one-component toner, the toner that has been removed by the cleaning device 7 is collected in the developing tank 10 of the developing device 4 and reused as a recycled toner.

In the early stage of image formation of the image forming apparatus, the developing tank 10 is filled with the initial toner, and the toner removed by the cleaning device 7 when the developing process is continuously performed. Is gradually returned to the developing tank 10 side of the developing device 4. At this time, the removed toner is at most about 20% of the amount of toner attached to the latent image on the photoconductor 1, and is collected in the developing tank 10 when the initial toner in the developing tank 10 is exhausted. start. At this time, the user is notified that the initial toner has run out, and the user replenishes the toner. In this toner replenishment, the initial toner is filled with, for example, a replenishment toner having a different amount of an external additive or a different material.

As a result, the recycled toner collected and reused contributes to the development with substantially the same characteristics as the initial toner, and it is possible to always obtain an image with a constant image quality.

That is, in the developing device using the one-component toner using the recycled toner, the one-component toner, like the two-component developer, lacks the external additive which affects the fluidity of the toner surface. Fluidity is deteriorated due to burial, and if this toner is used as it is, the developing roller 1
1, the amount of the toner thin layer is reduced and becomes non-uniform,
For example, image defects such as poor image density and white stripes are caused. In addition, the physical attraction force between the toners increases, causing toner aggregation, hindering the formation of the thin toner layer on the surface of the developing roller 11 described above, and causing white stripes and density defects due to missing images.

For this reason, development is carried out using a one-component toner, and the toner is removed by the cleaning device 7, collected in the developing device 4, and compensates for the above-mentioned fluidity when the toner is reused. Also, a toner different from the initial toner is replenished. For example, as the replenishing toner, an external additive having a larger amount or a material to which an external additive of a different type from that of the initial toner is added is used. As a result, the external additive of the replenishment toner is added to the recycled toner, thereby sufficiently compensating for fluidity and the like, and enabling stable development. As a result, while preventing a decrease in image density, it was possible to prevent a loss of an image due to a white stripe, and to maintain a constant image quality state.

The following examples show the effects of the present invention when a one-component toner is used.

(Embodiment 3) In an image forming apparatus, a general electrophotographic system shown in FIG. 1 is used, and a developing device 4 is developed with a one-component toner, particularly a non-magnetic one-component toner. Was done. Then, the residual toner remaining on the photoreceptor 1 is removed by the cleaning device 7, and this is connected to a connecting pipe.
The toner was directly collected to the developing tank 10 side by a collecting device including a conveying device 19 and a conveying means 20.

The composition of the one-component toner before the addition of the external additive is as follows: 90 parts by weight of polystyrene as a binder resin, 5 parts by weight of carbon black as a colorant, and 2 parts by weight of a charge control agent. And 3 parts by weight of a polyethylene wax as an anti-adhesive agent are sufficiently stirred and mixed with a mixer, and the mixture is kneaded with a screw extruder under heating. The kneaded product was cooled and then coarsely pulverized. The coarsely pulverized product was finely pulverized by a jet pulverizer, and the finely pulverized product was subjected to a classification treatment to obtain a toner having an average particle diameter of about 9 μm before external addition.

The toner obtained as described above is
As shown in Table 5 below, external additives of the types were stirred and mixed by a mixer to perform an external addition process, and the initial toner (toner No. 1) was used.
2) a replenishment toner (toner No. 13) in which the amount of external additives, particularly silica, was increased, and a replenishment toner (toner N) further added with another type of titanium oxide as an external additive.
o. 14) was produced.

[0125]

[Table 5]

The amounts of the various external additives shown in Table 5 indicate the ratios to 100 parts by weight of the toner before external addition.

Therefore, the toner No. is used as the initial toner. 1
2 is filled in the developing tank 10 to perform development. When the toner removed by the cleaning device 7 is returned to the developing tank 10 for the first time, toner No. 13 or 1
Table 4 below shows the results obtained when 40,000 copies were made by replenishing the toner of No. 4 and collecting and reusing the toner removed by the cleaning device 7, that is, the developing process.

In order to make a comparison with the above-described case, the toner N
o. The results obtained when the toner No. 12 was used are shown in RFE. As shown.

[0129]

[Table 6]

As can be understood from Table 6, when the amounts and types of the external additives of the initial toner and the replenishment toner are the same, white stripes gradually occur, resulting in image defects. On the other hand, by increasing the amount of the external additive of the replenishment toner or increasing the type of the external additive, it was possible to maintain a constant good image quality state in which white stripes and the like did not occur.

Further, as shown in FIG. 3, the change in image density is represented by toner No. By using 13 or 14, the image density in the initial state could be maintained even when 40,000 sheets were developed. However, the replenishment toner is changed to the same toner No. as the initial toner. By performing the development of 40,000 sheets using No. 12, the image density is in a constant state in the initial state, but the image density gradually decreases and recovers after the initial toner is collected in the developing tank 10. I never did.

As described above, in the image forming apparatus according to the present invention, the initial image forming apparatus is installed, the developing device 4 is replaced, or the developer in the developing tank 10 is replaced. When an image is formed by filling the initial toner and the replenishment toner which is depleted and newly replenished, the replenishment toner different from the initial toner is used, so that the toner removed by the cleaning device 4 is developed. Even when the toner is collected and reused as a recycled toner, a constant image quality state can always be maintained.
In this case, there is no need to take measures to supplement the charging performance and fluidity of the specially collected toner, and it is not necessary to separately provide it.
As described above, it suffices to simply make the toner for replenishment different from the initial toner, so that the user does not have to take any trouble and the developing device does not need to take any special measures. Further, maintenance and the like can also be reduced.

In the developing device 4, when a two-component developer is used, the toner removed by the cleaning device 7 is collected by a toner hopper 14 for replenishing the toner. However, it may be directly collected in the developing tank 10. This is because the collected toner is at least 20% or less of the toner that has been developed and adhered to the photoconductor 1 as described above.
The toner concentration in the developer within 0 does not greatly increase, and the toner concentration does not increase until image fogging occurs.

[0134]

According to the image forming apparatus of the present invention, when reusing a clogged unnecessary toner, the image quality can be reduced without taking any special measures such as guaranteeing the characteristics of the toner. Can be maintained at the same level as the initial state, and unnecessary toner is not generated, so that waste of toner is eliminated and resource saving can be achieved.

Further, the developer and especially the toner can be dealt with by changing the amount and type of the external additive for maintaining the fluidity and the like in a predetermined state without changing the composition itself, thereby increasing the cost of the developer. No connection.

In addition, since the user only needs to replenish the toner and does not need any special operation or skill, the handling becomes very simple.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an outline of an image forming apparatus that enables toner removed by a clowning device according to the present invention to be used as recycled toner.

FIG. 2 is a characteristic diagram illustrating a relationship between a fixing strength and the number of copies, illustrating a result of an example in the second embodiment of the present invention.

FIG. 3 is a characteristic diagram illustrating the relationship between image density and the number of copies, illustrating the results of an example according to the third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoreceptor 2 Charger 3 Optical image 4 Developing device 5 Transfer device 7 Cloning device 9 Developer 10 Developing tank 11 Developing roller 13 Toner replenishing device 14 Toner hopper (toner collecting part) 15 Replenishing roller 16 Cloning blade 17 Removal toner Container for temporarily storing the toner 18 Removed toner (recycled toner) 19 Connecting pipe (recovery device) 20 Transport means (recovery device) 21 New toner

Continued on the front page (72) Inventor Toru Yoshioka 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Inside (72) Inventor Masanori Matsumoto 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Inside Sharp Corporation

Claims (7)

[Claims] A developing device that includes a developing roller that conveys a developer including a toner to a developing area facing the image carrier; and a developing device that develops a latent image formed on the image carrier with the developer. After the transferred image is transferred to the transfer material, the toner remaining on the image carrier is removed by a cleaning device, and the removed toner is recovered to the developing device via a recovery device and reused as recycled toner. An image forming apparatus comprising: an initial developer charged into a developing device at an early stage of development; and a replenishing developer newly replenishing the initial developer. The toner includes an externally added toner different from the additive, and the replenishment developer is replaced with the initial developer, replenished, and reused together with the removed toner. Image type with developing device Apparatus. 2. The toner constituting the replenishment developer, which is treated with an external additive of a different amount from the external additive of the toner of the initial developer. An image forming apparatus comprising the developing device according to claim 1. 3. A latent image formed on the image carrier is developed by supplying a developer containing toner, and after the developed image is transferred to a transfer material, the toner remaining on the image carrier is removed. A developing device that reuses the removed toner as recycled toner, wherein the developer is initially charged and used in the developing device, and replenishment development is performed after the initial developer is used. Wherein the external additive added to the toner of the replenishment developer is different in amount or type from the external additive added to the toner of the initial developer. Developer used for 4. The developing method according to claim 3, wherein the external additive added to the toner is selected from materials that affect the fluidity or charging performance of the toner or the polishing of the image carrier. Developer used for equipment. 5. A latent image formed on the image carrier is developed by supplying a developer containing toner, and after the developed image is transferred to a transfer material, the toner remaining on the image carrier is removed. A developing device that reuses the removed toner as recycled toner, wherein the developer is initially charged and used in the developing device, and replenishment development is performed after the initial developer is used. Wherein the glass transition point and the melt viscosity of the binder resin constituting the toner of the replenishment developer are different from those of the toner of the initial developer. 6. A latent image formed on the image carrier is developed by supplying a developer containing toner, and after the developed image is transferred to a transfer material, the toner remaining on the image carrier is removed. A developing device in which the removed toner is reused as a recycled toner, wherein the developer is used initially filled in the developing device, and replenishment is performed after the initial developer is used. A developer for use in a developing device, comprising a developer, wherein an amount of an anti-adhesive constituting the toner of the replenishment developer is different from an amount of the anti-adhesive of the toner of the initial developer. 7. The developer according to claim 3, wherein said developer is composed of a one-component toner.