JPH02196255A - Developing device - Google Patents

Abstract

PURPOSE:To realize a developing device capable of non-contact development with thin layered toner by reducing circumferential speed of a toner feeder less than that of a toner feeding quantity control member. CONSTITUTION:The circumferential speed of the toner feeding quantity control member 12 is increased more than that of the toner feeder 9 and the member 12 is rotated in the opposite direction. Fluid shearing force and agitating force are generated be tween the member 12 and the toner feeder 9 and the electrostatically charged thin layered toner 8 is supplied for the toner feeder 9. The toner 8 which passed through the member 12 and a blade 13 is electrostatically charged and held by electrostatic mirror image force on the feeder 9 and fed close to a developing gap. Voltage is impressed between a holding part 2 and a conductive holding body 10 by means of a developing bias impressing means 16 and developing electric field is generated in response to the potential contrast of the electrostatic latent image of a latent image carrier 1. The toner 8 is permitted to fly toward the electrostatic latent image of the latent image carrier 1, the toner adhering quantity in response to potential contrast is obtained and the latent image is developed. The toner 8 is transferred to recording paper 18 using a transferring device 17, the toner 8 is fixed to the recording paper 18 by pressure, heat, etc., and the image is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developing device that visualizes an electrostatic latent image using toner.

[Prior Art] As disclosed in Japanese Patent Laid-Open No. 56-14264, a conventional developing device has been proposed in which a thin insulating layer is formed on the surface of a toner conveying member to prevent fluctuations in image density. .

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, when non-magnetic toner is used, the agitation effect by the magnetic brush cannot be obtained, so not only does the charge amount of the toner vary greatly, and the temperature also fluctuates greatly.
-Component There was a problem in that it was difficult to provide a color developing device using non-magnetic toner.

SUMMARY OF THE INVENTION The present invention is intended to solve these problems, and an object of the present invention is to provide a developing device that can obtain high image quality using a -component nonmagnetic developing method.

Still another object is to provide a developing device in which the amount of charge on toner that contributes to image temperature is stable. Still another object is to provide a developing device capable of producing full colors using -component non-magnetic toner. Still another object is to provide a developing device that is capable of non-contact development even when the toner is made into a thin layer and the development gap is made small.

[Means for Solving the Problems] In the developing device of the present invention, a toner conveying body is disposed adjacent to a latent image carrier that forms an electrostatic latent image, and the toner conveying body is insulated on a conductive support. In a developing device that forms a layer and makes an electrostatic latent image visible by electrostatically adhering the toner on a toner transport member to a latent image carrier, a conductive and cylindrical layer 17 adjacent to the toner transport member is used. A toner transport regulating member having the shape of
The peripheral speed of the toner transport body is smaller than the peripheral speed of the toner transport amount regulating member.

Further, the developing device of the present invention is characterized in that an electric field is applied between the toner transport body and the toner transport amount regulating member.

Furthermore, the developing device of the present invention has a 1-sq.
The thickness of the layer is smaller than the gap length between the toner transport body and the toner transport amount regulating member.

[Function] According to the above configuration of the present invention, even non-magnetic toner can be stably thinned by rotating the toner transport amount regulating member at high speed in the opposite direction to the toner transport member in a portion adjacent to the toner transport member. Alternatively, the toner can be supplied to the toner transport body by applying a high electric field to the toner near the insulating layer of the toner transport body by an electric field generating means to induce electric charge, or by using a toner transport amount regulating member, etc. Toner that is triboelectrically charged and has a stable charge amount can be supplied to the toner transport member, and the toner layer on the toner transport member can be thinned to reduce the development gap (the distance between the latent image carrier and the toner transport member). This makes it possible to reduce the gap between neighboring parts, and even when using insulating toner, a sufficient developing electrode effect can be obtained, and it becomes possible to create a developing device that can handle full color using -component non-magnetic toner. .

Hereinafter, the present invention will be explained in detail with reference to Examples.

[Example] FIG. 1 is a cross-sectional schematic view of a developing device in an example of the present invention, in which a latent image carrier 1 has a photoconductive layer 3 on a conductive support 2. After the photosensitive layer 3 is charged to a predetermined potential using a charger 4, light emitted from a light source 5 such as a laser is emitted using a rotating polygon mirror or the like (not shown). An image is formed on the photosensitive layer 3 by the imaging optical system 6 to obtain a potential contrast and an electrostatic latent image is formed on the latent image carrier 11, while the developing device 7 charges the toner 8 which is the image forming body. The toner is conveyed by a toner conveyor 9, which has a thin insulating layer 11 formed on a conductive support 10, and has a conductive layer adjacent to the toner conveyor 9. flexible and cylindrical)/ner conveyance amount regulating member 1
Similarly, an electrically conductive flat blade 13 is provided which regulates the amount of toner conveyed, makes it uniform, and prevents scattering, and the voltage applying means 14 is connected to the conductive support 10 and the toner conveying amount regulating member, respectively. 12 to generate a high electric field in the gap)--With the insulation resistance of the toner 8 reduced, charge is injected into the toner 8 from the toner conveyance amount regulating member 12 to control the toner 8 to a predetermined amount of charge. Alternatively, the toner 8 is charged to a predetermined amount of charge by frictional charging between the toner 8 and the toner transport amount regulating member 12, and the toner 8 adhering to the toner transport amount regulating member 12 is peeled off by a scraper 15. This prevents the toner 8 from agglomerating in the gap or clogging the gap. supplying a thin layer of charged toner 8 to the toner conveyance body 9 by rotating the toner conveyance amount regulating member 12 in the direction to generate fluid shearing force and stirring force in the gap between the toner conveyance amount regulating member 12 and the toner conveyance body 9. The toner 8 is transferred backward through the toner transport amount regulating member 12 and the blade 13, is charged, is held by the toner transport member 9 by electrostatic image force, and is transported to the developing gap (latent image carrier 1 and toner transport member 1). The potential of the electrostatic latent image on the latent image bearing member 1 is increased by applying a voltage between the supporting portion 2 and the conductive support 10 by the developing bias applying means 16. A developing electric field is generated according to the contrast, and the charged toner 8 is made to fly toward the electrostatic latent image on the latent image carrier 1 to obtain an amount of toner adhering according to the potential contrast, and the latent image is visualized. Then, the toner 8 adhering to the latent image carrier 1 is electrostatically transferred to the recording paper 18 by the transfer device 17, and the 1 henna 8 is fixed on the recording paper 18 by means such as pressure or heating to form a desired image. This is what you get. ] In the figure, toner conveying body 9
The circumferential speed of the toner conveyance amount regulating member 12 is 120 mm/see, and the circumferential speed of the toner conveyance amount regulating member 12 is 600 mm/see in the opposite direction to the toner conveyance body 9.
mm/sec, the gap between the toner transport body 9 and the toner transport amount regulating member 12 is 0.2 mm, and the gap between the conductive support 10 and the toner transport amount regulating member] 2 is 1,500 mm.
When a voltage of
It is possible to stably form a toner layer as thin as 1 mm, and the amount of charge of the toner 8 on the toner conveying body 9 is 15 mm.
A stable charge amount with small variation in μC/g and charge amount distribution is obtained, and the electrostatic latent image of the latent image carrier is visualized using toner 8 which has obtained such a stable charge amount. Accordingly, it was possible to form a toner image with high resolution and gradation, and when a semiconductor laser was used as the light source 5, it was possible to form a toner image with high resolution and excellent area gradation.

Incidentally, in FIG. 1, arrows indicate the rotation directions of the respective members, but the above-mentioned numerical values do not limit the present invention.

Further, regarding the toner transport body 9, the conductive support body 10 is as follows:
In addition to conductive non-magnetic metals such as aluminum and stainless steel, a wide range of conductive materials such as iron and conductive resin can be used.
When formed from resins such as phenol, polyester, aromatic, silicone elastomer, polyurethane, epoxy resin, polyimide, cellulose, and natural rubber, it has high insulation properties, is inexpensive, and has excellent moldability with a specific resistance of 101.
It is possible to form an insulating layer with a resistance of 2ΩCm or more, and by forming the insulating layer 11 with a photoconductive material such as selenium, zinc oxide, titanium oxide, cadmium sulfide, or an organic photoreceptor, the static electricity of the insulating layer can be removed by light. It is possible to provide a developing device that performs uniform charge removal by irradiation with a simple structure, obtains a stable toner layer surface potential, and always performs development in a constant state.

FIG. 2 shows the relationship between the toner conveying body and the toner conveying amount regulating member with respect to the circumferential speed ratio b/a between the circumferential speed a of the toner conveying body and the circumferential speed S of the toner conveying amount regulating member in another embodiment of the present invention. b
/ By making the value of a larger than 1, d /
The value of c can be made smaller than 1, the toner layer can be made sufficiently thin without increasing the precision of mechanical parts, and the mutual agitation effect between the toner transport body and the toner transport amount regulating member can be improved. Accordingly, toner charged to a predetermined amount can be selectively supplied to the toner conveying body. In addition, by controlling the circumferential speed ratio and making the toner layer thinner without increasing the precision of mechanical parts, the thickness of the toner layer can be made smaller than the gap length between the toner transport body and the toner transport amount regulating member. Make it smaller,
Even in a non-contact developing device in which the toner and the latent image carrier do not come into static contact, the development gap can be made small, and sufficient developing electrode effects can be obtained even without contact, producing images with high resolution and high resolution. It is possible to perform non-contact development using non-magnetic component toner, and it is possible to obtain excellent images with little color mixture even when used as a full-color developing device.

Although the embodiments have been described above, the present invention can be applied not only to the above embodiments but also to a wide range of developing devices such as electrophotographic recording devices, full-color printers, copying machines, and monochrome video printers that record television images. It is effective if applied to developing devices that use -component toner, such as copying machines, page printers, and facsimile machines.

[Effects of the Invention] As described above, according to the present invention, by making the circumferential speed of the toner transport body smaller than the circumferential speed of the toner transport amount regulating member, the toner can be made into a thin layer and the development gap can be reduced. To provide a developing device capable of non-contact development, capable of stabilizing the amount of charge of toner that contributes to image density, and capable of obtaining high image quality using a -component development method. -component non-magnetic toner -
Using this, it is possible to provide a developing device that can handle full color. Further, by applying an electric field between the toner transport body and the toner transport amount regulating member, the amount of charge on the toner can be stably controlled.

Furthermore, by making the thickness of the toner layer on the toner transport body smaller than the gap length between the toner transport body and the toner transport amount regulating member, the toner layer can be made thinner without using parts with high mechanical precision. This has the effect that it is possible to provide a developing device that can produce high-resolution and high-temperature images.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional schematic diagram of a developing device in an embodiment of the present invention, and FIG. 2 is a diagram showing the circumferential speed a of the toner conveying member and the circumferential speed of the toner conveyance amount regulating member in the second embodiment of the present invention. FIG. 3 is a diagram showing the amount of change in the length ratio d/C between the gap length C between the toner transport member and the toner transport amount regulating member and the thickness d of the toner layer on the toner transport member with respect to the circumferential speed ratio b/a. Latent image carrier Toner Toner carrier Conductive support Insulating layer Toner transport amount regulating member Above Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kizobe Meiki (1 other person) 1 Latent image carrier? b/a Figure 1 Figure 2

Claims (3)

[Claims] (1) A toner conveying body is disposed adjacent to a latent image carrier that forms an electrostatic latent image, and the toner conveying body is formed by forming an insulating layer on a conductive support, and the toner conveying body is formed by forming an insulating layer on a conductive support. In the developing device for making the electrostatic latent image visible by electrostatically adhering the toner to the latent image carrier, a conductive and cylindrical toner transport amount regulating member is provided adjacent to the toner transport member. A developing device characterized in that the peripheral speed of the toner transport body is smaller than the peripheral speed of the toner transport amount regulating member. (2) The developing device according to claim 1, wherein an electric field is applied between the toner transport body and the toner transport amount regulating member. (3) The developing device according to claim 1 or 2, wherein the thickness of the toner layer on the toner transport member is smaller than the gap length between the toner transport member and the toner transport amount regulating member.