JPH0627806A - Developing device - Google Patents

Abstract

PURPOSE:To stably develop all image from solid black image to a half tone image together with a fine line without having a defect in an image in a developing device using a nonmagnetic one-component developer. CONSTITUTION:A porous conductive elastic member 2 on which a high voltage is applied, supplies a developer T to a developer carrier 1, and simultaneously electrifies the developer T, a conductive layer thickness regulating plate 3 on which the high voltage is applied regulates the thickness of the layer of the developer T onto the developer carrier 1 to form the thin layer of the developer T on the developer carrier 1, and simultaneously electrify the developer T with a specific quantity, and the developer carrier 1 constituted is such a manner that a metallic shaft 1a on which the high voltage is applied is covered with a conductive resin layer 1b, carries the thin layer of the developer T to a developing region facing a photosensitive body 10 to move the developer T in an electric field between the latent image potential of the image on the photosensitive body 10 and the surface potential of the developer carrier 1, and to execute development. Then, the developer T remaining on the developer carrier 1 after the development is scraped off by the porous conductive elastic member 2.

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 developing an electrostatic latent image with a developer, and more particularly to a developing device using a non-magnetic one-component developer.

[0002]

2. Description of the Related Art Conventionally, as a developing method for developing an electrostatic latent image, for example, an electrostatic latent image formed on a uniformly charged photoconductor by exposure based on image information, generally a toner and a carrier are used. A developing method using a two-component developer, particularly a magnetic brush developing method (hereinafter, simply referred to as a two-component magnetic brush developing method) is often used.

However, the two-component magnetic brush developing method has practical problems that the developing device becomes large, it is difficult to stabilize the mixing ratio of the toner and the carrier, and it is difficult to stabilize the charging of the toner by stirring. I have

Recently, a magnetic brush developing method (hereinafter, referred to as a "magnetic brush developing method" using a one-component developer in which the toner itself has magnetism)
The one-component magnetic brush development method) has also been put to practical use.

However, although the one-component magnetic brush developing method can achieve miniaturization of the developing device, it leaves a problem in colorization because the developer contains magnetic powder.

From the above viewpoints, a developing method using a non-magnetic one-component developer (hereinafter, simply referred to as a non-magnetic one-component developing method) has been proposed and many studies have been conducted.

Even in the non-magnetic one-component developing method, the developing method is carried out so that the developer and the electrostatic latent image holding member (for example, a photoconductor) are in contact with each other, and the developing agent and the electrostatic latent image holding member are also used. And the method of developing the toner by flying the developer onto the electrostatic latent image holding member in a non-contact manner.

Although the former contact method is excellent in terms of improving the image density and supplying the developer, the background fog is likely to occur because the developer and the electrostatic latent image holding member are in contact with each other. There are drawbacks. Further, in the colorization in the future, the one-drum color superimposing one-time transfer method, which will simplify the structure of the entire apparatus and reduce the cost, cannot be adopted because of the contact type, which causes a problem of color mixing. There are drawbacks.

From the above, the latter non-contact and flight type non-magnetic one-component developing method is required.

[0010]

SUMMARY OF THE INVENTION In the conventional developing device using the non-contact and flying type non-magnetic one-component developing method described above,
Since a non-magnetic one-component developer is used, the developer is supplied onto the developer carrier, electrified, formed into a thin layer, conveyed to the development area, and controlled in flight force, as well as removed, stirred and circulated. However, there is a problem that an image defect such as an image blur occurs if the above is not performed sufficiently.

For example, a pressure contact blade 6 as shown in FIG.
In the conventional developing device which simultaneously charges the developer T and forms a thin layer by means of No. 3, the charge amount of the developer T is not stable due to frictional charging, and changes greatly in the material and surface condition of the pressing blade 63. There was a problem that it was affected and lacked reliability.

The developer carrying member 6 is not used for development.
The developer T remaining on the developer carrier 1 is not removed from the developer carrier 61, and the developer T remaining on the developer carrier 6 is not removed.
Since it is used for the next development with the rotation of 1, the stability of the charge amount of the developer T and the stirring property of the developer T are also problems.

Further, the gap g between the developer carrying member 61 and the electrostatic latent image holding member 62 must be set to a very small value of 0.5 to 0.02 mm, which is conventionally used in aluminum or stainless steel. When a developer carrier 61 made of metal such as steel is used, if the developing bias applied from the high voltage power source 64 to the developer carrier 61 is set high, the developer carrier 61 and the electrostatic latent image carrier 62 are There is a drawback that discharge is caused between the two and the image is deteriorated, and when the developing bias is set low, sufficient developability may not be ensured. In order to prevent such a problem, if the insulating developer carrier 61 is used, the developing electrode effect disappears, and the reproducibility of a solid black image deteriorates.

In view of the above points, an object of the present invention is to provide the functions of supplying developer, charging, forming a thin layer, conveying to a developing area, controlling flight force, removing, stirring and circulating, In particular, a porous conductive elastic member that is involved in the supply, removal and charging of the developer, a conductive regulating member that is involved in stabilizing the charging of the developer, and a conductive resin layer that stabilizes the flight of the developer. It is an object of the present invention to provide a developing device capable of stably developing an image from a solid black to a halftone together with a fine line without an image defect by providing a developer carrying member having a surface.

Another object of the present invention is to supply developer, charge, form a thin layer, convey to a developing area, control flight force,
A fibrous conductive member that is involved in supply, removal and charging of the developer, and a conductive regulating member that is involved in stabilizing the charging of the developer, while having respective functional parts for removing, stirring and circulating. By providing a developer carrying member having a conductive resin layer on the surface for stably flying the agent, it is possible to stably develop an image from solid black to halftone with fine lines without image defects. It is to provide a developing device.

[0016]

SUMMARY OF THE INVENTION A developing device of the present invention comprises a developer carrier having a metal carrier coated with a conductive resin layer, and rotatably arranged in contact with the developer carrier. The porous conductive elastic member and the developer carrying layer to regulate the layer thickness of the developer to form a thin layer of the developer on the developer carrying body and a predetermined amount with respect to the developer. And a high voltage is applied to each of the developer carrying member, the porous conductive elastic member, and the conductive restricting member.

Further, the developing device of the present invention comprises a developer carrier comprising a metal carrier coated with a conductive resin layer, and a fibrous member rotatably arranged in contact with the developer carrier. A conductive member and a conductive member that regulates the layer thickness of the developer on the developer carrier to form a thin layer of the developer on the developer carrier and charges the developer by a predetermined amount. And a high voltage is applied to each of the developer carrying member, the fibrous conductive member, and the conductive restricting member.

[0018]

In the developing device of the present invention, the porous conductive elastic member to which a high voltage is applied supplies the developer to the developer carrying member and charges the developer, so that the high voltage is applied. The conductive regulating member regulates the layer thickness of the developer on the developer carrier to form a thin layer of the developer on the developer carrier, and at the same time charges the developer by a predetermined amount, An electrostatic latent image holding member carries a thin layer of the developer to a developing area facing the electrostatic latent image holding member by a developer carrying member formed by coating a conductive resin layer on a metal carrier to which a voltage is applied. Development is performed by causing the developer to move in the electric field between the image latent image potential above and the surface potential of the developer carrier, and the porous conductive elastic member remains on the developer carrier after development. Scrap off the developer.

Further, in the developing device of the present invention, the fibrous conductive member to which a high voltage is applied supplies the developer to the developer carrying member and charges the developer so that the high voltage is applied. The conductive regulating member regulates the layer thickness of the developer on the developer carrying member to form a thin layer of the developer on the developer carrying member and performs a predetermined amount of charging on the developer, A developer carrier made by coating a conductive resin layer on a metal carrier to which a high voltage is applied conveys a thin layer of developer to the development area facing the electrostatic latent image carrier and holds the electrostatic latent image. Development is performed by causing the developer to move in the electric field between the image latent image potential on the body and the surface potential of the developer carrier, and the fibrous conductive member remains on the developer carrier after development. Scrap off the developer.

[0020]

The present invention will be described in detail with reference to the drawings.

<First Embodiment> FIG. 1 is a sectional view showing the arrangement of a developing apparatus according to the first embodiment of the present invention. The developing device according to the present embodiment includes a developer carrier 1 rotatably supported so as to face a photoconductor (electrostatic latent image carrier) 10 on which an electrostatic latent image is formed with a gap g, and a developer carrier. Development is performed by regulating the layer thickness of a roller-shaped porous conductive elastic member 2 rotatably supported while partly contacting the body 1 and a nonmagnetic one-component developer (hereinafter, simply referred to as developer) T. Conductive layer thickness regulating plate (conductivity regulating member) that forms a thin layer of the developer T on the agent carrier 1 and charges the developer T by a predetermined amount.
3, a stirring paddle 5 for stirring the developer T in the developer supply section, a leakage prevention cover 6 for preventing the developer T from leaking from the upper portion of the developer carrier 1, and the above-mentioned members to attach the developer T. Developer container 7 forming a developer supply section for accommodating
And a high-voltage power source E1 connected to the porous conductive elastic member 2.
And a high-voltage power supply E2 connected to the conductive layer thickness regulating plate 3,
The main part is composed of a high voltage power source E3 connected to the developer carrying member 1.

The developer carrying member 1 has a specific resistance of 10 ⁴ to 10 ¹² which is made of a resin in which conductive powder is dispersed on a metal shaft (metal carrier) 1 a such as aluminum or stainless steel.
It is formed by covering the conductive resin layer 1b having a thickness of Ωcm and a thickness of 1.5 to 5 mm.

The conductive powder includes conductive carbon, aluminum powder, silver powder and the like, and the resin includes thermosetting resin such as phenol resin, urea resin, melamine resin and thermoplastic resin such as polystyrene resin and acrylic resin. Resins may be mentioned.

The conductive resin layer 1b has a specific resistance of 10 ⁴ to 1 by dispersing 5 to 50% by weight of conductive powder in the resin.
0 ¹² [Omega] cm is capable of a range of coating on the metal shaft 1a of the conductive resin layer 1b forms a cylindrical cylinder made of a conductive resin, which a conductive adhesive to the metal shaft 1a It is carried out by adhering by means such as the above, or by press-fitting into the metal shaft 1a. The specific resistance 1 is placed on the metal shaft 1a.
As a method for providing the conductive resin layer 1b having a resistance of 0 ⁴ to 10 ¹² Ωcm, a polyurethane resin in which a conductive powder having a specific resistance of 10 ⁴ to 10 ¹² Ωcm such as conductive carbon, aluminum powder or silver powder is dispersed is used. There is also a method of applying a coating material such as a polyester resin or the like, but with this method, the adhesive force of the conductive resin layer 1b to the metal shaft 1a is insufficient, and there is a risk of peeling during long-term use. It is not practical because it may cause pinholes. Moreover, the specific resistance 10 in which the conductive powder is dispersed except for the flange portions on both sides without the metal shaft 1a is provided.
There is also a method in which the cylindrical cylinder itself made of a conductive resin of ⁴ to 10 ¹² Ωcm is used as the developer carrying member, but the high voltage power source E3
The voltage applied from is not uniform in the longitudinal direction of the developer carrier, especially the outer diameter is 30 mm or less and the length is 200 mm.
In the case above, there is a possibility that deflection due to insufficient rigidity may occur, and it is difficult to secure the roundness of the developer carrier, which is related to the most important density unevenness of the image. There is.

The porous conductive elastic member 2 is made of a material such as soft polyurethane foam having a three-dimensional skeletal structure containing conductive carbon and is a metal supported by the wall of the developing tank container 7 and rotatable. It is formed in a roll shape on the shaft 2a. To bond the porous conductive elastic member 2 to the metal shaft 2a, a conductive adhesive such as a silver (Au) filler-containing epoxy adhesive or a carbon filler-containing acrylic adhesive is used. The porous conductive elastic member 2 has a specific resistance of 10
^{3-10 6} is about [Omega] cm, and since the conductive resin layer 1b of the developer carrying member 1 is in the specific resistance ¹⁰ 4 ^{~10 12} Ωcm, the high pressure is connected to the porous conductive resilient member 2 Power There is no leakage between E1 and the high voltage power source E3 connected to the developer carrying member 1, and the porous conductive elastic member 2 and the developer carrying member 1 can maintain their respective high voltage potentials. There is. The polarity of the high voltage power source E1 and the charging polarity of the developer T are the same.

The porosity level of the porous conductive elastic member 2 is preferably 15 or more and 45 or less per 25 mm as the number of cells (holes). Further, the contact depth (the amount of bite) of the porous conductive elastic member 2 to the developer carrying member 1 is
From the viewpoint of the transportability of the developer T and the effect of removing the developer T remaining on the developer carrier 1 after development, 0.5 to 1.0.
mm was experimentally good.

The conductive layer thickness regulating plate 3 is made of a silicone rubber plate or the like having a hardness of about 60 to 80 ° which is made conductive by dispersing or adhering a conductive material (for example, conductive carbon) to a thickness of 2 to 2. It is formed to about 3 mm. In the conductive layer thickness regulating plate 3, the antinode portion or the antinode portion and the edge portion are in contact with the developer carrier 1, and the developer T of about 20 to 40 μm is defined by the contact pressure.
So that a thin layer of T is formed on the developer carrier 1.
The layer thickness is regulated, and the developer T is charged with a predetermined amount.

The conductive layer thickness regulating plate 3 has a specific resistance of 10 ³ to.
10 ¹⁰ is about [Omega] cm, and since the conductive resin layer 1b of the developer carrying member 1 is in the specific resistance ¹⁰ 4 ^{to 10 12} [Omega] cm, a high voltage power source E2 which are connected to the conductive layer thickness regulating plate 3 High-voltage power supply E3 connected to developer carrier 1
There is no leak between the conductive layer thickness regulating plate 3 and the developer carrying member 1, and the high voltage potentials of the conductive layer thickness regulating plate 3 and the developer carrying member 1 can be maintained. The polarity of the high voltage power source E2 and the charging polarity of the developer T are the same.

The stirring paddle 5 is not particularly limited in shape and the like, but has a shape effective for stirring and circulating the developer T in the developer supply portion in the developer tank container 7, and It is preferable that the retention portion or the agglomeration portion of the agent T is not formed.

The leakage prevention cover 6 is preferably formed with a thickness of about 0.02 mm.

Developer carrier 1, porous conductive elastic member 2
The stirring paddle 5 and the stirring paddle 5 are connected to each other outside the developing tank container 7 via a gear (not shown) so that they are simultaneously rotated in the directions indicated by the arrows with the operation of the developing process.

Next, the operation of the developing device of the first embodiment thus constructed will be described.

When the operation of the developing process is started, the developer carrier 1, the porous conductive elastic member 2 and the stirring paddle 5 are formed.
Respectively start rotating in the directions indicated by the arrows.

The developer T contained in the developer supply portion in the developing tank container 7 is rotated by the porous conductive elastic member 2 when the porous conductive elastic member 2 and the stirring paddle 5 start to rotate. 2, it is carried to the contact portion between the porous conductive elastic member 2 and the developer carrying member 1. Here, the developer T is charged by being charged by the porous conductive elastic member 2 connected to the high voltage power source E1.

The developer T, which has been charged with electric charge from the porous conductive elastic member 2, moves as shown in FIG. 2 as the developer carrier 1 and the porous conductive elastic member 2 rotate.
A part is regulated to a thickness of about 20 to 40 μm by the conductive layer thickness regulating plate 3 to form a thin layer on the developer carrying member 1, and at the same time, a charge is applied from the conductive layer thickness regulating plate 3 to be stable. The predetermined charge amount is controlled. The adhesive force between the developer carrier 1 and the developer T at this time is an electrostatic force between the electric charge of the developer T and the conductive resin layer 1b of the developer carrier 1.

The thin layer of the developer T formed on the developer carrying member 1 is carried to the developing area for developing the photoconductor 10 on which the electrostatic latent image is formed, as the developer carrying member 1 rotates. The photoconductor 10 has a distance of (gap g−thin layer thickness of the developer T).
I will be facing.

A high-voltage power source E3 is connected to the developer carrying member 1 and the surface charge densities of the image area and the non-image area on the photoconductor 10 are different in the developing area. Assuming that the charge amount is q and the electric field at the position in the developing area is E, the force F = qE acting on the developer T is different between the image portion and the non-image portion, and the developer T is only on the image portion. It flies from 1 to the photoconductor 10 side and shifts. At that time, the conductive resin layer 1b of the developer carrying member 1 has a specific resistance in the range of 10 ⁴ to 10 ¹² Ωcm, preferably about 10 ⁸ Ωcm, so that the developer T from solid black to a halftone image can be obtained. Develops well without being excessively transferred. At this time, even if the output of the high-voltage power supply E3 fluctuates, the fluctuation as an image is reduced because the conductive resin layer 1b of the developer carrying member 1 has resistance.

In order to secure the image density, the photoconductor 10
It is an effective method to keep the peripheral speed of the developer carrying member 1 higher than the peripheral speed.

The developer T on the developer carrying member 1 which has not been used for development is stored in the developer supplying section in the developing tank container 7 as the developer carrying member 1 is rotated so that the developer T of the leak preventing cover 6 can be stored again. Is conveyed in the direction. The leakage prevention cover 6 is in contact with the developer carrying member 1 but is in soft contact therewith,
Further, since the developer T hits the curved portion, the developer T is guided by the leakage prevention cover 6 into the developing tank container 7 without being stripped from the developer carrier 1.

The developer T remaining on the developer carrying member 1 introduced into the developing tank container 7 is conveyed toward the porous conductive elastic member 2 as shown in FIG. The conductive elastic member 2 scrapes off the developer carrying member 1,
As shown in (2) in FIG. 2, the porous conductive elastic member 2 is rotated and carried toward the stirring paddle 5 in the developing tank container 7. Therefore, the developer T is circulated and stirred in the developing tank container 7 so as to contribute to the development again.

Here, making the peripheral speed of the porous conductive elastic member 2 faster than the peripheral speed of the developer carrying member 1 has an effect of scraping off the developer T remaining on the developer carrying member 1. Not only can it be improved, but it is also effective in supplying the developer T to the developer carrying member 1 by the porous conductive elastic member 2 for the next developing process cycle and charging it.

By repeating the above operation, the developing process proceeds.

With the consumption of the developer T, the developing tank container 7
When the developer T is replenished to the developer supply section in the inside, it can be done by opening the supply lid 7a, or by a cartridge.

In the developer supply section in the developing tank container 7, the residual developer T and the unused developer T are mixed as the developer T, but all the developer T that contributes to the photoreceptor 10 by adhesion. Since the porous conductive elastic member 2 and the conductive layer thickness regulating plate 3 are brought into contact with each other and transported, the charge amount is controlled by the charge imparted there, and the charge amount is stable regardless of the history of the developer T until then. Become. This stabilizes the flight force F = qE of the developer T to the image portion, which is most important for development, and stabilizes the image.

Although a DC power supply is shown as the high-voltage power supply E1, it is also effective to use a DC + AC superimposed power supply in order to prevent the developer T from aggregating and improve the transportability. However, it is necessary that there is a direct current component such that the polarity of the developer T does not change even when the alternating current is superposed.

In the developing device of the first embodiment shown in FIG. 1, the conductive layer thickness regulating plate 3 is composed of a single member, but the conductive layer thickness regulating plate 3 is not limited to this. However, as shown in FIGS. 3 (a) to 3 (c), if the portion including the surface in contact with the developer carrying member 1 can apply a high voltage and has a predetermined specific resistance, that portion is The function of the conductive layer thickness regulating plate 3 is satisfied by providing a mechanical contact condition with the developer carrying member 1 by the supporting member. FIG. 3A shows an example of the conductive layer thickness regulating plate 3 in which the conductive material 32 is formed on the surface of the elastic material 31 such as urethane rubber. Although there is a method of coating the conductive material 32 on the elastic material 31, the method of joining with an adhesive or the mechanical fixing method is more stable in terms of life and stability. Further, FIG. 3B shows that a conductive material 34 is attached to the tip of an elastic metal plate 33 such as phosphor bronze or spring steel.
Another example of the conductive layer thickness regulating plate 3 in which is fixed is shown. Further, in FIG. 3C, a conductive material 37 is formed on the surface of the elastic material 36 and is fixed to the tip of an elastic metal plate 35 such as phosphor bronze or spring steel. Another example is shown.

<Second Embodiment> FIG. 4 is a sectional view showing the arrangement of a developing apparatus according to the second embodiment of the present invention. In the developing device of this embodiment, a fibrous conductive member 8 is used instead of the porous conductive elastic member 2 in the developing device of the first embodiment shown in FIG. Therefore,
The other members are configured in the same manner as the members in the developing device of the first embodiment shown in FIG. 1, so corresponding members are designated by the same reference numerals and detailed description thereof is omitted.

The fibrous conductive member 8 is, for example, a conductive resin fiber such as nylon or rayon in which conductive carbon is dispersed, or a conductive resin such as nylon or rayon having a conductive material layer in the center. The fibers are formed into a brush shape. For making the fibers conductive, there is also a method of making the conductive carbon or the like fine particles and attaching them to the surface to make them conductive by a post-treatment. As the conductive resin fiber, the thickness of hair is 100 to 2000 denier / 100, that is, 1
The thickness when the material of g is stretched to 9000m is 1 denier, and 1 to 20 denier (100 to 100 denier)
It is considered appropriate that the density is 2000 denier and the density is about (10 to 1000) × 10 ³ per square inch.

Like the porous conductive elastic member 2, the fibrous conductive member 8 is formed like a brush on a rotatable metal shaft 8a supported by the wall of the developing tank container 7. As in the case of the porous conductive elastic member 2, the fibrous conductive member 8 is bonded to the metal shaft 8a by using a conductive material such as a silver (Au) filler-containing epoxy adhesive or a carbon filler-containing acrylic adhesive. Adhesive is used.

By setting the contact depth of the fibrous conductive member 8 with the developer carrying member 1 to be about 0.5 to 2.0 mm, the desired function can be provided.

Although the rotational speed of the fibrous conductive member 8 varies depending on the diameter of the fibrous conductive member 8, it is preferable that the peripheral speed is equal to or higher than the peripheral speed of the developer carrying member 1. The points are the same as in the case of the porous conductive elastic member 2.

Regarding the operation of the developing device of the second embodiment,
It goes without saying that it is almost the same as the case of the developing device of the first embodiment shown in FIG.

<Third Embodiment> FIG. 5 is a sectional view showing a developing device according to a third embodiment of the present invention. The developing device of this embodiment is an example in which the rotation direction of the developer carrying member 1 in the developing device of the first embodiment shown in FIG. 1 is reversed. Therefore, the corresponding members are configured similarly to the members in the developing device of the first embodiment shown in FIG. 1 except for the following, so that the corresponding members are designated by the same reference numerals. The detailed description thereof is omitted.

In the developing device of the third embodiment, the conductive layer thickness regulating plate 3 is arranged on the upper side of the developer carrying member 1, and the leakage prevention cover 6 is arranged on the lower side. Further, the stirring paddle 5 is provided above the porous conductive elastic member 2 in the developing tank container 7.
To prevent the developer T in the vicinity from directly reaching the developer carrying member 1 without being involved in the porous conductive elastic member 2 and being carried to the developing zone in forming a thin layer by the conductive layer thickness regulating plate 3. The developer T that has been blocked and the developer T remaining after development is recovered by the developer tank 1 as the developer carrier 1 rotates and scraped off by the porous conductive elastic member 2. A partition plate 9 having a shape to be introduced near the stirring paddle 5 in the developing tank container 7 is provided.

The partition plate 9 may be made of resin or the like,
It is effective that the developer T is formed of a metal material and grounded in view of the charge of the developer T and the chargeability of the developer T thereafter.

Although the partition plate 9 may contact the porous conductive elastic member 2, the porous conductive elastic member 2 is not
^Since it has a specific resistance of about ³ to 10 ⁶ Ωcm, it does not leak the high voltage of the high voltage power source E1.

The operation of the developing device of the third embodiment is almost the same as that of the developing device of the first embodiment shown in FIG. Also in the case of the developing device of the third embodiment, the porous conductive elastic member 2 is used.
Instead of the above, it is possible to provide the fibrous conductive member 8 like the developing device of the second embodiment shown in FIG. Further, the rotation direction of the porous conductive elastic member 2 is an example,
The rotation may be reversed. Also in this case, the partition plate 9 should be provided.

By the way, in each of the above-mentioned examples, as a result of various experiments, good images were obtained under the following conditions. Gap g 0.1 mm Specific resistance of conductive resin layer 1b 10 ¹⁰ Ωcm Peripheral speed of developer carrier 1 75 mm / sec Specific resistance of porous conductive elastic member 2 (or fibrous conductive member 8) 10 ⁴ Ωcm Porous voltage 4 00V high-voltage power supply Shitsushirube conductive elastic member 2 (or fibrous conductive member 8) voltage 6 00V high-voltage power supply E2 specific resistance 10 ⁶ [Omega] cm high voltage source E1 of the peripheral speed 125 mm / sec conductive layer thickness regulating plate 3 Voltage of E3 500V Peripheral speed of the photoconductor 10 50mm / sec Voltage of image part on the photoconductor 10 50V Voltage of non-image part on the photoconductor 10 600V (reverse development)

Further, it is possible to control the image density depending on the magnitude relation of the power sources of the high voltage power sources E1, E2 and E3. For example, | voltage of the high voltage power source E1 >> | voltage of the high voltage power source E3 | Image temperature increases with
Even when the voltage of the high-voltage power source E2 | <| the voltage of the high-voltage power source E3 |, the image density increased . The image density increased even when the voltage of the power source E3 was set to |.

In each of the above-described embodiments, the case of the developing device using the positive charging type developer T has been described, but the present invention is also applicable to the developing device using the negative charging type developer T. Needless to say, it is applicable to.

[0061]

As described above, according to the present invention,
It had the functions of supplying developer, charging, forming a thin layer, conveying to the developing zone, controlling flight force, removing, stirring, and circulating, which are important in forming a development process using a non-magnetic one-component developer. In particular, by providing a developer carrying member formed by coating a conductive resin layer on a metal carrier, a porous conductive elastic member or a fibrous conductive member and a conductive regulating member, In addition to eliminating the instability of the developing conditions due to the structure that ignores triboelectric charging and the flow of the developer, the developing electrode effect of the developer carrying member can be set to a condition that favorably develops from solid black to halftone image development. , It is easy to set appropriate development conditions such as fine line reproduction can be set well (that is, each parameter can be set individually), and stable image development can be realized. Come, there is an effect that becomes excellent also in terms of reliability.

Further, due to the internal structure of the developing device, even when foreign matter is mixed in, it reaches the upper vicinity of the porous conductive elastic member or the fibrous conductive member, but thereafter the porous conductive elastic member or Since the developer is sent by the fibrous conductive member, foreign matter rarely proceeds to the next step, and there is an effect that the reliability becomes excellent also in this respect.

Further, in terms of environmental characteristics, the frictional charging method, which is greatly affected by the surrounding environment and the surface condition of the material, is not used, so that there is an effect that stable characteristics are exhibited.

Furthermore, by using the developer carrying member in which the conductive carrier layer is coated on the metal carrier, the image fluctuation is small and the fog does not occur when the developing bias is applied to the developer carrying member. The effect that a sharp image is not obtained, there is no fear of discharge due to the application of a high-voltage developing bias, and it is possible to achieve mechanically high precision even with a small-diameter and long-sized developer carrier. There is.

Further, the image temperature can be controlled by controlling the voltage applied to the developer carrying member, the porous conductive elastic member or the fibrous conductive member, and the conductive regulating member. Even if the electric resistance of the constituent members fluctuates or the lots vary, it is possible to adjust the image density level by controlling each applied voltage.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a developing device according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of an essential part showing the flow of developer in the developing device of the first embodiment shown in FIG.

3 is a cross-sectional view showing a modified row of the conductive layer thickness regulating plate in FIG.

FIG. 4 is a sectional view showing the structure of a developing device according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a developing device according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing an example of a conventional developing device.

[Explanation of symbols]

 1 Developer Carrier 1a Metal Shaft (Metal Carrier) 1b Conductive Resin Layer 2 Porous Conductive Elastic Member 2a Metal Shaft 3 Conductive Layer Thickness Control Plate (Conductive Control Member) 5 Stirring Paddle 6 Leak Prevention Cover 7 Development Tank container 7a Supply lid 8 Fibrous conductive member 8a Metal shaft 9 Partition plate 10 Photoconductor (electrostatic latent image holder) E1, E2, E3 High-voltage power supply T Developer

Claims (2)

[Claims] 1. A developer carrier comprising a metal carrier coated with a conductive resin layer, and a porous conductive elastic member rotatably disposed in contact with the developer carrier, A conductive regulating member for regulating the layer thickness of the developer on the developer carrier to form a thin layer of the developer on the developer carrier and for charging the developer by a predetermined amount. At the same time, a high voltage is applied to the developer carrying member, the porous conductive elastic member, and the conductivity regulating member, respectively. 2. A developer carrier comprising a metal carrier coated with a conductive resin layer, a fibrous conductive member rotatably arranged in contact with the developer carrier, and the developing device. A conductive regulating portion B for regulating the layer thickness of the developer on the developer carrier to form a thin layer of the developer on the developer carrier and charging the developer with a predetermined amount. At the same time, a high voltage is applied to the developer carrier, the fibrous conductive member, and the conductivity regulating member, respectively.