JPH0455873A - Developing device - Google Patents

Abstract

PURPOSE:To obtain an image without the unevenness of density by providing a recessed and projecting part along the turning direction of a developer supply means on a surface where the developer supply means abuts on a developer carrier. CONSTITUTION:The recessed and projecting part is provided along the turning direction of the developer supply means 5 on the surface where the developer supply means 5 abuts on the developer carrier 3 so that the total surface area of the projecting part of the recessed ad projecting part may be 10-40% of total surface area. For example, the means 5 is an elastic roller having foaming skeleton sponge structure. Thus, the thin layer of one-component developer whose thickness is proper and where triboelectricity is uniformized is formed on the carrier 3, and the image without the unevenness of density is obtained by development even when the grain size of the developer is made small.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. The present invention provides an image forming apparatus such as a copying device, an image recording device, a printer, a facsimile, etc., in which an image formed on an image bearing member made of an electrophotographic photoreceptor, an electrostatic recording dielectric material, etc. The present invention relates to a developing device used to develop and visualize an electrostatic latent image, and particularly to a developing device that develops using a one-component developer that does not contain a carrier.

In image forming devices such as copying machines, image recording devices, printers, and facsimile machines, an electrostatic latent image formed on an image carrier made of an electrophotographic photoreceptor or an electrostatic recording dielectric material is
The image is developed using a developing device and visualized as a toner image.

As one of such developing devices, various dry component developing devices have been proposed and put into practical use. However, in any developing device, it is difficult to form a thin layer of toner, which is a component developer, on a developer carrier.

However, as improvements in image resolution, sharpness, etc. are currently required, it is essential to develop a method for forming a thin layer of toner and an apparatus for the same, and several measures have been proposed for this purpose. .

For example, as shown in Japanese Patent Application Laid-open No. 54-43038, an elastic blade made of rubber or metal is brought into contact with the developing sleeve of the developer carrier, and toner is passed between the contact portion of the elastic blade and the developing sleeve. By passing and regulating
A thin layer of toner is formed on the developing sleeve, and sufficient triboelectricity is imparted to the toner by friction at the contact portion.

In this case, when regulating the non-magnetic toner with the elastic blade, a separate toner supply member is required to supply the toner onto the developing sleeve. This is because in the case of magnetic toner, the toner can be supplied onto the developing sleeve by the magnetic force of the magnet in the developing sleeve, but in the case of non-magnetic toner, toner cannot be supplied by magnetic force.

Therefore, the present applicant proposed a developing device shown in FIG. 7 in Japanese Patent Laid-Open No. 58-116559.

In the conventional developing device proposed above, in the developing container 2 containing the non-magnetic toner 6 as the -component developer, a fur coat is placed in contact with the developing sleeve 3 at a position upstream of the elastic blade 4 in the rotational direction of the developing sleeve 3. Elastic roller 1 with brush structure
5 is installed so that the toner 6 remaining on the developing sleeve 3 without being consumed by development is removed by an elastic roller 15, and new toner 6 is supplied onto the developing sleeve 3.

According to this, a thin layer of non-magnetic toner 6 can be satisfactorily formed on the developing sleeve 3, and the electrostatic latent image on the photoreceptor 1 can be satisfactorily developed. It is now possible to faithfully reproduce a solid black image of an area and always obtain a stable image.

However, with the recent increase in the quality of copied images, there has been a call for smaller particle diameter developer, but if toner with small particle diameter is used in the developing device proposed above, , it is not always possible to obtain a sufficiently good image.

This is due to the following reason.

That is, since toner with a small particle size (average particle size of about 8 μm or less) has a larger surface area per unit volume than toner with a normal particle size (average particle size of about 10 to 12 μm), the developing sleeve 3
There is a high probability of friction with
The adhesion force due to the mirroring force with the sleeve 3 is large (the toner remaining on the developing sleeve 3 without being consumed in development tends to be insufficiently removed by the elastic roller 15, and the toner remains on the developing sleeve without being peeled off). The toner remaining on the developing sleeve is mixed with the newly supplied toner on the developing sleeve and sent to the contact area with the elastic blade, where it is frictionally charged together with the new toner. At this time, the new toner is charged and given the proper triboelectricity, whereas the remaining toner is triboelectrically charged again from the state where it originally had the proper triboelectricity, so it is not excessively charged. This excessively charged toner is less likely to be used for development than toner that has been given an appropriate triboelectric charge, and density unevenness occurs in the image obtained by development.In particular, the toner thin layer on the developing sleeve 3 In the case of non-contact development in which development is performed by forming an alternating electric field between the developing sleeve 3 and the photoreceptor 1 without bringing the toner into contact with the photoreceptor 1, density unevenness becomes noticeable.

In order to prevent the above-mentioned problems such as uneven image density, it is necessary to improve the ability of the elastic roller 15 to remove the toner remaining on the developing sleeve 3.

As described above, the elastic roller 15 has the function of not only removing the toner 6 from the developing sleeve but also supplying the developer onto the developing sleeve 3.

With regard to the toner supplying ability of the elastic roller 15, it must be kept in mind that especially when toner of small particle size is used, the fluidity of the toner of small particle size is poorer than that of toner of normal particle size.

Therefore, by making full use of both the toner 6 peeling and supplying capabilities, a good amount of toner 6 can be deposited on the developing sleeve 3.
In order to form a thin layer and obtain a good image without density unevenness through development, it is desirable to understand and appropriately define the factors that affect both of the elastic rollers 15.

Therefore, an object of the present invention is to reliably strip off the one-component developer remaining on the developer carrier without being consumed during development and supply new developer, so that the developer can be properly coated on the developer carrier. A developer that forms a thin layer of a one-component developer with a uniform triboelectric layer thickness and a uniform triboelectric layer, making it possible to easily obtain images with uniform density even when the particle size of the developer is reduced. The purpose is to provide equipment.

The above-mentioned object is achieved by the developing device according to the present invention. To summarize, the present invention supplies a one-component developer contained in a developer container onto a developer carrier by a developer supply means rotating in the opposite direction at a contact portion with the developer carrier, and causes the developer to be carried thereon. While the developer is formed into a thin layer by an elastic regulating member that is in contact with the developer carrier, the developer is transported by the developer carrier to a developing section facing the image carrier, and the image is formed. In a developing device that develops a latent image formed on a carrier, the surface of the developer supplying means that comes into contact with the developer carrying member is provided with an uneven portion along the rotating direction of the developer supplying means. The total surface area of the convex portions of the uneven portion is 10 of the total surface area.
40%. According to one aspect of the present invention, the developer supply means is an elastic roller having a foam skeleton-like sponge structure.

15F Examples of the present invention will be described in detail below.

FIG. 1 is a schematic diagram showing an embodiment of the developing device of the present invention.

In FIG. 1, reference numeral 2 denotes a developer container containing non-magnetic toner 6 as a one-component developer, and the present developing device includes an image carrier that rotates in the direction of arrow a in the figure as a developer carrier in the developer container 2. A developing sleeve 3 is provided facing the photoreceptor l,
The electrostatic latent image on the photoreceptor 1 is developed and visualized as a toner image.

The photoreceptor 1 is, for example, a so-called xerographic photoreceptor that forms an electrostatic latent image by the Carlson process,
2-23910, a photoreceptor with an insulating layer on the surface that forms an electrostatic latent image by the NP process, an insulator that forms an electrostatic latent image by an electrostatic recording method, and a photoreceptor that forms an electrostatic latent image by a transfer method. The electrostatic latent image (
(containing a potential latent image) is used.

The developer container 2 has an opening extending in the longitudinal direction of the developing device (perpendicular to the plane of the paper), and the above-mentioned developing sleeve 3 is provided in the opening.

The developing sleeve 3 is made of a material such as aluminum or SUS. The developing sleeve 3 has its right half-circumferential surface inserted into the developer container 2 when viewed from the opening diagram, and its left half-circumferential surface exposed to the outside of the developing container 2 so as to face the photoreceptor 1.
It is horizontally installed and can be rotated freely. Developing sleeve 3 and photoreceptor 1
A small gap is provided between the two. The developing sleeve 3 is rotationally driven in the direction of the arrow with respect to the rotational direction a of the photoreceptor 1.

Note that the developer carrier is not limited to a cylindrical body (sleeve) like the developing sleeve 3, but may be in the form of an endless belt that is rotationally driven. Alternatively, a conductive rubber roller may be used.

Further, in the developer container 2, an elastic blade 4 is provided above the developer sleeve 3 as an elastic regulating member, and an elastic roller 5 is provided at a position upstream of the elastic blade 4 in the rotational direction of the developer sleeve 3. .

The elastic blade 4 is provided so as to be inclined downward toward the upstream side in the rotational direction of the developing sleeve 3.
is in contact with the upper outer circumferential surface of the rotor, facing in the rotational direction.

The elastic roller 5 is in contact with a portion of the developing sleeve 3 on the side opposite to the photoreceptor 1, and is rotatably supported.

In the developing device, with the above configuration, the elastic roller 5 rotates in the direction of arrow C, and the rotation of the elastic roller 5 carries the toner 6 and supplies it to the vicinity of the developing sleeve 3. The toner 6 on the elastic roller 5 rubs against the developing sleeve 3 at the abutting portion (the protruding portion) and adheres to the developing sleeve 3 .

Thereafter, as the developing sleeve 3 rotates, the toner 6 adhering to the developing sleeve 3 enters between the elastic blade 4 and the developing sleeve 3 at the abutting part thereof, and when passing through this, the toner 6 adhering to the developing sleeve 3 enters between them. It is rubbed by both the surface and the elastic blade 4 and is sufficiently charged by friction.

The toner 6 charged in the above manner pulls out the abutting portion between the elastic blade 4 and the developing sleeve 3, forms a thin layer of toner 6 on the developing sleeve 3, and is attached to the photoreceptor 1. The toner is transported to the opposing developing unit with a small gap between them. In the developing section, between the developing sleeve 3 and the photoreceptor 1,
By applying an alternating voltage of direct current and alternating current as a developing bias, the toner 6 on the developing sleeve 3 is transferred in correspondence with the electrostatic latent image on the photoreceptor 1, adheres to the electrostatic latent image, and is developed. Visualize as a toner image.

The toner 6 remaining on the developing sleeve 3 without being consumed by development in the developing section is collected into the developing container 2 from the lower part of the developing sleeve 3 as the developing sleeve 3 rotates.

A sealing member 7 is provided in the toner collecting portion of the developer container 2. The sealing member 7 allows the toner 6 remaining on the developing sleeve 3 to pass into the developing container 2, and
Toner 6 in the developer container 2 is prevented from leaking from the lower part of the container 2.

The toner 6 collected in the developing container 2 is peeled off from the developing sleeve 3 by the elastic roller 5 at the contact portion with the developing sleeve 3. At the same time, new toner 6 is supplied onto the developing sleeve 3 by the rotation of the elastic roller 5, and the new toner 6 is conveyed to the contact area between the developing sleeve 3 and the elastic blade 4 as the developing sleeve 3 rotates again. be done.

On the other hand, most of the peeled toner 6 is conveyed and mixed with the toner 6 in the developer container 2 as the elastic roller 5 rotates, and the electrical charge of the peeled toner 6 is dispersed. Ru.

Now, the surface of the above-mentioned developing sleeve 3 is formed with a moderately uneven rough surface, which increases the probability of friction between the surface of the developing sleeve 3 and the toner 6, and improves the conveyance of the toner 6. I'm letting you do it.

This uneven rough surface can be formed by sandblasting the surface of the developing sleeve 3 with irregularly shaped alundum abrasive grains or with regular shaped glass beads so that the surface roughness Rz is 1 to 10 μm. It has gained. Alternatively, a rough surface of the projections is formed on the surface of the developing sleeve 3 using conductive particles such as metal oxide particles, graphite, carbon, etc., which can form projections by themselves, and the rough surface of the projections is formed. The particles may be bound with a binder resin such as a phenol resin or a fluororesin so that the surface of the binder resin forms recesses, thereby providing the surface of the developing sleeve 3 with an uneven rough surface.

In this embodiment, the developing sleeve 3 has a diameter of 16 mm as a base body.
An aluminum sleeve with a diameter of 1.5 mm was used, and the surface of the sleeve was subjected to a blasting process using regular glass beads (#600) to give a surface roughness Rz of about 4 μm.

As mentioned above, the elastic blade 4 is in pressure contact with the developing sleeve 3, and applies the toner 6 that has entered between them under pressure onto the developing sleeve 3 to form a thin layer of the toner 6. Let it form.

The elastic blade 4 is made of a rubber material such as silicone or urethane (with a hardness of 40° to 90° as specified by JISA).
), and a part of the surface of the elastic blade 4 facing the developing sleeve 3 comes into surface contact and presses the developing sleeve 3.

In the present invention, the contact pressure of the elastic blade 4 to the developing sleeve 3 is 5 to 200 linear pressure in the generatrix direction of the developing sleeve 3.
g/cm is preferable, and in this example, a urethane rubber blade with a hardness of 65° and a thickness of 1° and 2 mm was used as the elastic blade 4, and this was brought into contact with the developing sleeve 3 with a linear pressure of 50 g/cm.

The nonmagnetic toner 6 is used as a nonmagnetic component developer, and is made by dispersing a pigment such as carbon in various thermoplastic resins such as styrene resin, acrylic resin, and polyethylene resin. In this example, toner 6 is a toner powder with an average particle size of 8 μm made of a styrene/acrylic resin, a styrene/butadiene resin copolymer, and a pigment.
The material to which 1.0% colloidal silica was externally added was used.

Next, the elastic roller 5 will be explained in detail.

As described above, the elastic roller 5 has the functions of both stripping off the toner 6 remaining on the developing sleeve 3 and supplying new toner 6.

When the supply of new toner 6 onto the developing sleeve 3 by the elastic roller 5 is insufficient, if a solid black image with a high image ratio is developed, the image will be lower than the image developed in the first rotation of the developing sleeve 3. A phenomenon occurs in which the density of images developed after the second rotation becomes lighter. This means that the amount of toner supplied by the elastic roller 5 is smaller than the amount of toner consumed by the first rotation of the developing sleeve 3.

The phenomenon that occurs when the toner 6 remaining on the developing sleeve 3 without being consumed in development is not sufficiently removed by the elastic roller 5 is as explained in Section 2 of the prior art section.

That is, the toner 6 remaining on the developing sleeve 3 without being consumed by development in the developing section is sent to the contact portion with the elastic roller 5 as the developing sleeve 30 rotates, and is stripped off by the elastic roller 5. Remaining toner 6 removed by elastic roller 5
If the toner 6 is not peeled off and remains on the developing sleeve 3, it passes through the contact area between the elastic roller 5 and the developing sleeve 3, and the toner 6 that is not removed and remains on the developing sleeve 3 passes through the contact area between the elastic roller 5 and the developing sleeve 3, and the new toner 6 supplied by the elastic roller 5 passes through the contact area between the elastic roller 5 and the developing sleeve 3. Mixed with the toner 6, the elastic blade 4
The toner is sent to the contact portion between the toner and the developing sleeve 3, where it is subjected to frictional electrification together with new toner 6.

At this time, the new toner 6 is charged and given an appropriate triboelectricity, whereas the remaining toner 6 is triboelectrically charged again from the state where it originally had a proper triboelectricity, so it becomes excessively charged. be done. This excessively charged toner 6
Compared to the toner 6 that has been given a proper tribo, the mirroring force with the developing sleeve 3 is greater and the toner adheres firmly to the developing sleeve 3, making it difficult for the toner to fly in the developing section and to be used for development. , the image obtained by development causes density unevenness as a whole.

In this embodiment, as shown in FIG. 2, the elastic roller 5 is an elastic roller having a foam skeleton-like sponge structure in which a metal core 51 is provided with a sponge body 52 such as polyurethane foam or rubber sponge. FIG. 3 shows a plan view of the surface of the zero-elastic roller 5 that comes into contact with the developing sleeve 3, that is, the outer circumferential surface.

As shown in FIG. 3, the sponge body 52 of the elastic roller 5 has a structure in which air bubbles are surrounded by partition walls of the sponge.
On the surface of the sponge body 52, the air bubbles are exposed as concave portions 52a, and the partition walls are exposed as convex portions 52b.

According to such an elastic roller 5, the toner 6 remaining on the developing sleeve 3 is removed by rubbing the developing sleeve 3 with the convex portion 52b of the sponge body 52 as it rotates. Also, as the toner 6 rotates, new toner 6 is held in the recess 52a and on the convex part 52b, conveyed, and rubbed against the developing sleeve 3 by the convex part 52b, thereby supplying and adhering the new toner 6 to the developing sleeve 3. will be carried out.

According to the experiments of the present inventor, in order to stably strip off the toner 6 remaining on the developing sleeve 3 and supply new toner 6 by the elastic roller 5, it is necessary to use the sponge body 5.
The function of the convex portion 52b of No. 2 is important, and when the elastic roller 5 is configured without the convex portion 52b, for example, when the surface layer is a skin layer of urethane rubber, it exhibits the specified performance at the initial stage of use. However, if the developing operation is repeated, the effect of rubbing the toner 6 on the developing sleeve 3 becomes too strong, causing the toner 6 to fuse onto the developing sleeve 3, which is not desirable. Furthermore, since the pressure acting on the toner 6 is too strong, it also results in accelerated deterioration of the toner 6 itself.

On the other hand, if the elastic roller 5 having the convex portion 52b on the sponge body 52 is used as in this embodiment, it is possible to stably remove the remaining toner 6 on the developing sleeve 3 and supply new toner 6. can be done.

The direction of rotation of the elastic roller 5 is preferably opposite to the direction of the arrow C with respect to the developing sleeve 3 rotating in the direction of the arrow A at the contact portion with the developing sleeve 3. If this direction is set in the forward direction, the elastic roller 5 The toner 6 is placed on the developing sleeve 3 by
could not be sufficiently supplied, which was not desirable.

Now, as mentioned above, the sponge body 52 of the elastic roller 5
The convex portion 52b removes the remaining toner 6 on the developing sleeve 3.
This is an influential factor that has a strong influence on the removal of toner 6 and the supply of new toner 6.

Therefore, in order to find appropriate conditions for the above-mentioned influencing factors, we determined the ratio of the total area of the surface of the convex portion 52b to the total area of the surface of the sponge body 52 of the elastic roller 5, that is, the ratio of the total area of the surface of the convex portion 52b to the total area of the surface of the sponge body 52 of the elastic roller 5, that is, the area occupied by the shaded portion of the total area in FIG. An image formation experiment was conducted and examined by changing the area ratio into multiple stages.

The elastic roller 5 used was one with an outer diameter of 14 mm, in which a metal core 51 with an outer diameter of 5 mm was coated with polyurethane foam (trade name: Malt Filter) as a sponge body 52 in the form of a roller.

The area ratio of the surface of the convex portion 52b of the sponge body 52 is 10.
5 types of 15.25.40.50%, sponge body 52
By heat-treating five identical elastic rollers covered with polyurethane foam to different degrees of foaming of the polyurethane foam, the area ratio of the surface of the convex portion 52b of the sponge body 52 was reduced to 10.15 as described above.
．． Five types of elastic rollers were obtained with a ratio of 25%, 40%, and 50%.

The above five types of elastic rollers are used as the elastic roller 5 of the developing device shown in FIG.
5, development was carried out while the remaining toner 6 on the developing sleeve 3 was removed and new toner 6 was supplied, a copying operation was performed, and the image quality of the obtained image was examined. In addition, regarding the deterioration in image quality due to continuous copying of a large number of sheets, 2000 sheets were continuously copied and the deterioration in image quality at that time was investigated.

There are various causes and phenomena of image quality deterioration due to continuous copying of a large number of sheets mentioned above.
This occurs when the peeling and supplying ability of the material is increased too much.

When toner particles are damaged by an external force, the charging ability of the toner particles decreases and they are unable to receive appropriate triboelectric charging, and the damaged toner particles are not consumed in development, but as copying operations are repeated. It gradually accumulates in the developer container 2. When the proportion of damaged toner particles in the developer container 2 increases, the probability of rubbing between the damaged toner and normal toner increases, and the amount of toner with an inverted polarity opposite to the desired polarity increases. This results in so-called inversion fog, which is caused by adhesion to non-image areas on the photoreceptor. The above is the details of image quality deterioration due to continuous copying of a large number of sheets.

The experimental conditions were such that the surface potential of the electrostatic latent image on the photoreceptor 1 was changed to -
600V, bright area -150V, the gap between the photoreceptor 1 and the developing sleeve 3 is 250LLm, and the developing bias applied between the photoreceptor 1 and the developing sleeve 3 is set at a frequency of 18.
A DC voltage of -250V was superimposed on an AC voltage of 00Hz and a peak-to-peak voltage of 1200V. Further, the circumferential speed of the developing sleeve 3 was set to 70 mm/sec while the circumferential speed (process speed) of the photoreceptor 1 was approximately 50 mm/sec.

The elastic roller 5 is brought into contact with the developing sleeve 3 shown in FIG. 2 with a contact width d of 5 mm, and the direction of rotation at the contact portion is opposite to that of the developing sleeve 3 as described above.
It rotated at a circumferential speed of 50 mm/sec.

When experiments were conducted under the above conditions, the results shown in Table 1 were obtained.

When the area ratio of the convex portion of the sponge body 52 of the first front elastic roller 5 is decreased, the remaining toner 6 on the developing sleeve 3 is insufficiently removed by the elastic roller 5 and the new toner 6 is insufficiently supplied. As shown in Table 1, in terms of image quality, when the convex area ratio was 8%, the followability of solid black images deteriorated slightly due to insufficient supply of toner 6, and image unevenness also occurred due to insufficient peeling. . When the area ratio of the convex portions was 10% or more, neither the phenomenon of deterioration in followability of a solid black image due to insufficient supply of toner 6 nor the phenomenon of image unevenness due to insufficient peeling occurred.

On the other hand, regarding image quality deterioration due to continuous copying of a large number of sheets (indicated as image quality deterioration due to durability in Table 1), the above-mentioned elastic roller with a urethane rubber skin layer as its surface layer (
That is, image quality deterioration occurred when the convex area ratio was 100%, but in this experiment, image quality deterioration occurred even when the convex area ratio was 50%. When the convex area ratio was 40% or less, image quality deterioration due to continuous copying of a large number of sheets did not occur.

As is clear from the above, the area ratio of the convex portion of the elastic roller 5 is preferably set to 10 to 40%, thereby stabilizing the removal of the toner 6 remaining on the developing sleeve 3 and the supply of new toner 6. By doing so, it is possible to obtain a good image without deterioration in image quality through development.

FIG. 4 is a side view showing an elastic roller in another embodiment of the developing device of the present invention. In this embodiment, an elastic layer 72 made of a foam adhered and covered in a cylindrical shape is provided on a metal core 71, and a rubber skin layer made of a rubber material such as urethane rubber or silicone rubber is provided on the elastic layer 72. The feature is that an elastic roller 17 having a structure provided with a roller 73 is used.

As shown in the figure, the surface of the rubber skin layer 73 of the elastic roller 17 is provided with a groove-shaped recess 73a extending in the axial direction of the roller 17, thereby forming an uneven part in the circumferential direction. By adjusting the width, the area ratio of the total area of the surface of the convex portion 73b to the total area of the surface of the rubber skin layer 73 is set within the above-mentioned range of 10 to 40%.

In this embodiment, the width of the concave portion 73a is 1.5 mm, and the width of the convex portion 73a is 1.5 mm.
The width of b is 0.8 mm, and the area ratio of the convex portion 73b is 3.
It was set at 5%.

With such an elastic roller 17, as in the previous embodiment, it is possible to stably remove the toner 6 remaining on the developing sleeve 3 and supply new toner 6, and there is no deterioration in image quality due to development. Good images can be obtained.

In the above description, groove-shaped recesses 73a extending in the axial direction of the roller 17 are provided in the rubber skin layer 73 of the elastic roller 17 to form irregularities in the circumferential direction. By providing groove-like recesses inclined with respect to the direction, uneven portions may be formed in the rubber skin layer 73 in the circumferential direction. An annular recess extending in the circumferential direction is provided in the rubber skin layer 73 to form a roller 1.
If the axially uneven portion 7 is formed in an annular shape, the remaining toner 6 will not be removed and new toner 6 will not be supplied at all at the location of the developing sleeve 3 corresponding to the annular recess. It cannot be adopted.

FIG. 5 is a side view showing an elastic roller in still another embodiment of the developing device of the present invention, and FIG. 6 is a plan view showing a mesh member provided on the elastic roller of FIG. 5.

In this embodiment, as shown in FIG.
An elastic layer 8 made of foam adhered and coated in a cylindrical shape on top.
2 is provided, and nylon, Teflon, PT is provided on the elastic layer 82.
Elastic roller 1 configured with a mesh member 83 such as FE
The feature is that 8 is used.

As shown in FIG. 6, the mesh member 83 is formed in a grid shape, and the elastic roller 1 rotates in the direction of the arrow.
The grid portion 83b of the mesh member 83 is provided on the elastic layer 82 in an oblique position with respect to the axis of the mesh member 83.

As a result, the mesh member 83 is attached to the surface of the elastic roller 18.
An uneven portion is formed in the circumferential direction, with the hollow portion 83a as a recess and the lattice portion 83b as a convex portion. The area ratio of the total area of the surface of the convex portions consisting of the lattice portions 83b to the total area of the surface of the rubber elastic layer 82 is within the range of 10 to 40% described above.

With the elastic roller 18 as described above, as in the previous embodiment, the remaining toner 6 on the developing sleeve 3 can be removed stably and new toner 6 can be supplied, and image quality deterioration due to development can be prevented. No good images can be obtained.

Furthermore, by forming the mesh member 83 from a material that has a low coefficient of friction with respect to the developing sleeve 3, there is an advantage that the torque of the driving source of the developing device that obtains the driving force for the developing sleeve 3 etc. can be reduced.

In all of the above embodiments, the toner 6 of the -component developer is
Although non-magnetic toner is used as the embodiment, magnetic toner may be used by installing a magnet inside the developing sleeve 3. Further, although no bias voltage was applied to the elastic roller, the elastic roller may be made semi-conductive and a bias voltage may be applied for the purpose of peeling off the toner 6 on the developing sleeve 3, etc.

New Year's J Since the contoured uneven portions were provided such that the total surface area of the convex portions of the uneven portions was 10 to 40% of the total surface area, one component remaining on the developer carrier without being consumed during development. The developer supply means reliably strips off the developer and supplies new developer to form a thin layer of one-component developer with an appropriate layer thickness and uniform tribo on the developer carrier. Therefore, even if the particle size of the developer is reduced, ghosting can be prevented and a uniform image can be easily obtained once developed, making it possible to faithfully create high-density, wide-area solid black images. Can be reproduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the developing device of the present invention. 2 is a side view showing a part of the elastic roller provided in the developing device of FIG. 1. FIG. FIG. 3 is a plan view showing a portion of the elastic roller. FIG. 4 is a side view showing an elastic roller in another embodiment of the developing device of the present invention. FIG. 5 is a side view showing an elastic roller in still another embodiment of the developing device of the present invention. 6 is a plan view showing a mesh member provided on the elastic roller of FIG. 5. FIG. FIG. 7 is a schematic configuration diagram showing a conventional developing device. : Photoreceptor: Developing container: Developing sleeve: Elastic blade 7.18: Elastic roller: Toner 73b: Convex portion; Grid portion 5, 152 b 1 3b Fig. 3 Fig. 2 Fig. 4

Claims (1)

[Scope of Claims] 1) A one-component developer contained in a developer container is supplied onto a developer carrier by a developer supply means that rotates in the opposite direction at a portion in contact with the developer carrier, and is caused to be carried thereon. , while the developer is formed into a thin layer by an elastic regulating member that is in contact with the developer carrier, the developer is transported by the developer carrier to a developing section facing the image carrier; In a developing device that develops a latent image formed on an image carrier, a surface of the developer supplying unit that comes into contact with the developer carrier is provided with an uneven portion along the rotating direction of the developer supplying unit, A developing device characterized in that the total area of the convex portions of the uneven portions is 10 to 40% of the total surface area. 2) The developing device according to claim 1, wherein the developer supplying means is an elastic roller having a foam skeleton-like sponge structure.