JPS6015073B2 - image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus capable of repeatedly forming images using a material having an optomagnetic effect.

As a conventional image forming device, an electronic copying device pre-charges a photoreceptor having a photoconductive layer, exposes the original image to form an electrostatic latent image, develops it, and transfers and fixes the visible image onto copy paper to create a copy. At the same time, the photoreceptor was cleaned so that it could be used repeatedly. However, it has been difficult to increase the copying speed because the above-mentioned one-shot process is repeated even when a large number of identical copies are obtained. The purpose of the present invention is to repeatedly obtain the same information at high speed without repeating the pre-charging and exposure processes as in the electronic copying process. means for forming a latent image, means for developing the magnetic latent image on the photoreceptor, means for transferring the visible image by the developing means onto a recording medium, means for fixing the transferred image, and the photoreceptor after transfer. An image forming apparatus having a cleaning means is provided.

That is, the photoreceptor is made of a material that has an opto-magnetic effect, and is also made to be exchangeable as a transfer master.

The optomagnetic effect is thought to be caused by the change in the magnetic properties of a magnetic material in response to irradiation and interruption of light, that is, the rearrangement of magnetic ions caused by the movement of electrons induced by light irradiation. It is being The present invention attempts to form an image pattern according to brightness and darkness by directly attaching ferromagnetic toner to the optical magnetic material by utilizing development in which the magnetic permeability of bright areas decreases (see Figure 1) when imagewise exposed to the optical magnetic material. Moreover, once the image is exposed, the pattern is memorized even after development and transfer, so that copies can be made repeatedly.

Materials used for the photoreceptor include yttrium ion garnet (YIG) and yttrium ion garnet doped with a certain amount of impurities, such as Y (S).
i), Y (Ni), Y3Fe5-xSN0,2 [X<
0.05], and gadolinium ion garnet (G
dIG) and gadolinium ion garnet doped with specific impurities, such as GdIG (Fe), G
There is dIG(Pb).

In addition, manganese bismuth alloys, manganese germanium and its impurity additives, europium oxide, europium sulfide, selenide, etc. can also be used. Manganese alloys and rare earth gadolinium are particularly effective because they can be used at room temperature. These optical magnetic materials are manufactured into sintered bodies or vapor-deposited films by sputtering, chemical paper deposition, or the like. In the case of Akatsuki Consolidation, it is applied to the substrate in advance, and after bonding, it is polished to make the surface uniform. When forming a photosensitive plate for a copying machine, it is produced by forming a coating film for forming on a drum substrate that can withstand temperatures sufficiently higher than the phosphorizing temperature.

The embodiment shown in FIG. 2 will be explained below. The entire surface of the photosensitive drum 1 is coated with gadolinium yttrium garnet, which is a magnetic material 2 exhibiting an opto-magnetic effect.

Thereafter, the pattern from the original document 3 is projected to form a magnetic latent image on the optical magnetic drum as in a normal copying apparatus.

The photosensitive wavelength is 6328A, the temperature at which exposure patterns can be written is 18° C., and a normal tungsten light bulb is used as the light source 4. Sensitivity is 0.1-0. Desk j/It is a mountainside. After exposure, the magnetic latent image is developed by a developer 5 containing magnetic ink or magnetic toner.

For example, magnetic toner is made by mixing metals such as Fe, Co, and Ni and ferromagnetic particles such as ferrite with resin for heat fixing. Often, ferromagnetic particles may be surrounded by resin, resin may be surrounded by ferromagnetic particles, or a single particle structure may be formed in which resin and ferromagnetic particles are mixed. Furthermore, if necessary, a pigment may be added with color copying in mind. The magnetic toner is charged with a corona charger or a developing electrode to improve adhesion to the photoreceptor and transfer to copy paper.

Since the unexposed areas of the exposure pattern have a higher magnetic permeability (3mm) than the exposed areas, magnetic toner adheres to the unexposed areas.

Therefore, a positive image can be obtained. The pattern resolution after development obtained by the present invention is 50 to 100 lines/
It was a fence and showed higher resolution than normal copying equipment.
4 Further, the image is transferred onto the paper 7 fed from the paper feed roller 6 by the charger 10' and fixed by the fixing device 8. Furthermore, for repeated copying, the erasing heater 9 is not activated, the photosensitive drum continues to rotate, and the developing unit 5 performs development and transfer again in the same manner as described above.

Charger 10 also facilitates separation of copy paper from the drum.

It is also possible to provide a cleaning blade for removing toner after transfer, if necessary. In addition, when erasing the exposed pattern and forming a new pattern, the erasing heater 9
By raising the temperature to 28° C. or higher, the molten image pattern on the optical magnetic drum can be erased.

Erasing is also possible with an alternating magnetic field. In the case of the present invention,
Although it depends on the characteristics of the optical magnetic material used, if the difference in magnetic permeability does not become large due to exposure, it is possible to sensitize it by applying a slight magnetic field.

In that case, a magnetic field of about 100 Oelsted is required during or before exposure or thereafter before development. Furthermore, if the optical magnetic material is covered with a photoconductive layer that is transparent to the light of the previously sensitive wavelength and a pre-charging process is taken into consideration, a magnetic electrostatic latent image is formed and the contrast of the latent image is improved.

Further, in the present invention, it is also possible to form a magnetic pattern corresponding to the original image by primary magnetizing the magnetic material and exposing it to light.

Furthermore, it is possible to form a latent image pattern by scanning exposure (light modulation, deflection) of a laser beam, and it can be used as a computer output printer. That is, by utilizing the magnetic change caused by light irradiation and the thermal effect of the laser beam,
Furthermore, it is possible to increase the sensitivity by performing a type of thermal sensitization. In other words, this is interpreted to be due to the fact that the movement of electrons induced by light irradiation is further accelerated by thermal energy, thereby promoting the movement of electrons and hastening the rearrangement of magnetic ions. It is distinguished from phase transition caused by mere application of heat above the Curie point. For example, material G
The sensitivity and recording speed can be increased by carrying out the process in the present invention using dIG and a He-Ne laser (15 W output) as the light source. Figure 3 shows the characteristics of the magnetic material and laser.

As described above, in the present invention, a magnetic material is exposed to light to form a latent image, and this is developed and transferred to obtain a visible image, making it possible to repeatedly form images through a simple process and achieve high-speed recording. can. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the optical characteristics of the optical magnetic material, FIG. 2 shows the image forming apparatus according to the present invention, and FIG. 3 shows the various properties of the magnetic material. In FIG. The developing device 9 is an erasing heater.

Figure 1 Rare Z figure Figure 5

Claims (1)

[Claims] 1. A magnetic photoreceptor having an optomagnetic effect, a means for exposing the magnetic photoreceptor to optical information to form a magnetic latent image with reduced magnetic permeability in bright areas, and developing the magnetic latent image on the photoreceptor. An image forming apparatus comprising: means for transferring a visible image produced by the developing means onto a recording medium; means for fixing the transferred image; and means for cleaning the photoreceptor after the transfer.