JPH0143954B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying apparatus using an electrophotographic method.

Conventionally, copying devices using this type of electrophotography method are basically called the Carlson method, in which a photoreceptor is charged, the document to be copied is exposed to light, and the formed latent image is exposed to light using a developer. A process in which a visible image is developed on the surface of the photoreceptor, transferred to paper using the force of an electrostatic field, the developer remaining on the surface of the photoreceptor is then cleaned using a cleaning mechanism, and the residual potential is removed using static-eliminating light. is often used.

In recent years, efforts have been made to improve the reliability of this process and to lower the cost of the apparatus, and in particular, attempts have been made to simplify the mechanism in the developing section. One of these is so-called one-component development using magnetic toner, but in order to obtain good image quality, it is desirable to make it somewhat conductive and develop by charge injection. It has the disadvantage of being difficult to transfer.

Furthermore, fusing is required to fix the visible image formed on the paper, and heat roll or pressure fixing methods are used, but they tend to get stuck in the paper in the fuser unit, make the device complicated, and are not reliable. It was causing a decline in sexuality.

The purpose of the present invention is to use simpler one-component toner development in the developing section, and to apply pressure to transfer and fix at the same time so as not to be affected by the conductivity of the paper, so as to obtain a good image. It is an object of the present invention to provide a copying apparatus which has a simpler structure, improved reliability, and reduced device cost.

The present invention is characterized in that amorphous silicon is used for the photoreceptor that forms the latent photoimage, conductive one-component toner is used for development, and transfer and fixing are performed simultaneously by applying pressure. It is something.

Next, embodiments of the present invention will be described with reference to the drawings.

In the figure, a latent image of the original 3 is formed when a photoreceptor 1 is charged with an electric charge by a charger 2 using corona discharge and an original 3 is exposed on the surface of the photoreceptor 1 by an exposure system 4. The image is developed into a visible image by the developing device 5. Paper is fed from the hopper 6 in synchronization with the transfer timing, and the transfer roller 7
The image is pressed against the photoreceptor with strong force to transfer the image onto the paper and fix it at the same time. Even if pressure transfer is performed, some toner image remains on the photoreceptor surface. This is removed by a cleaner mechanism 8 (often by a blade 11), and the charge remaining on the surface of the photoreceptor is removed by light from a static eliminator 9, and the electrophotographic process is completed.

When using magnetic toner as a single-component toner, if the toner is non-conductive, electrophotographic development using the force of an electrostatic field cannot be performed unless the toner is charged. However, without a carrier, it cannot be charged properly and many In this case, it is not possible to create a good image. In order to obtain a good image, if the powder image is made conductive, a good powder image can be obtained on the surface of the photoreceptor, but this has not been possible because it is difficult to transfer the powder image. This point also applies to development using a conductive developer.

However, it has been known that this problem can be solved by using a pressure roller for transfer, but if pressure is applied with a strong force, depending on the hardness of the photoreceptor, it may cause scratches on its surface, making it unusable. With a conventional photoreceptor, Se-Te has a Bitkers hardness of about 65°.
About 120° for Se ₃ As ₂ , and too soft for other organic materials. At this level, even a pressure of several kilograms can cause damage. However, if the photoreceptor is made of amorphous silicon, the surface hardness is Vickers hardness.
Since it is extremely high at 1200 to 1800 degrees, it will not be damaged even under pressure of about 20 kg/cm. If it exceeds this limit, scratches will occur and the product will become unusable. With this level of pressure, sufficient fixation can be achieved at about 15 kg/cm by slightly modifying the physical properties of the toner. Therefore, in conventional two-component development, there is no need to replace the developer at the end of its life, or there is no need for a control mechanism to keep the toner concentration constant. There is no need for simple toner concentration control of the developing device, and the developing system is simple without worrying about developer life, and furthermore, it is possible to achieve a simple process in which transfer and fixing by a pressure roller are performed simultaneously.

As described above, the present invention uses amorphous silicon for the photoreceptor, uses a conductive one-component toner for development, and transfers and fixes simultaneously by applying pressure, which simplifies the structure and reduces equipment costs. This has the effect of improving reliability.

[Brief explanation of drawings]

The figure is a schematic diagram of a copying apparatus using an electrophotographic method, which is an embodiment of the present invention. 1... Photoreceptor, 2... Charger, 4... Exposure system,
5...Developer, 7...Transfer roller.

Claims (1)

[Claims] 1. In a copying device using an electrophotographic method, amorphous silicon is used for the photoreceptor that forms the latent image, a conductive one-component toner is used as the developer, and transfer and fixing are performed simultaneously by applying pressure. A copying device characterized by: