JPS6013186B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for forming an image according to a magnetic latent image using a material having a magneto-optical effect.

Conventionally, as a device for forming a visible image from a magnetic molten image, there is a device as disclosed in Japanese Patent Publication No. 90342, ie, a device that visualizes a magnetic latent image written on a magnetic material by sprinkling magnetic toner on it with a magnetic head. Are known. This cannot be used to create a visible image from an optical image, so-called copying. Another device is the one described in U.S. Pat. No. 3,717,460, in which a magnetic material and a photoconductive material are used to form a pattern of different conductivity on the photoconductive material according to an optical image, and the magnetic material is electrically connected to the photoconductive material through the conductivity pattern. A known technique is to heat the magnetic latent image to form a magnetic latent image, which is then visualized by sprinkling toner on it. This requires electrical heating, which makes the device complicated. In addition, a known electronic copying device pre-charges a photoreceptor having a photoconductive layer, exposes the original image to form a static latent image, develops the image, transfers and fixes the visible image onto copy paper, and obtains a copy. 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 present invention provides an image forming apparatus that uses a magnetic material having a magneto-optic effect and eliminates the above-mentioned drawbacks.

That is, a magnetic latent image is formed in advance on a material having a magneto-optical effect such as the magnetic Faraday effect or Kerr effect, and this magnetic latent image is generated as an optical density image, which is then projected and transferred onto a photoconductive material. An electrostatic latent image is formed on the image forming apparatus, and this latent image is developed to form an image. By forming these materials into a drum, multiple copies can be made from a single latent image. There are two methods for forming a magnetic image on a magneto-optical material: one is to scan the material with a well-known recording magnetic head and convert the electrical signal into a magnetic port image, and the other is to irradiate a light pattern image onto the material and use the action of light. There are those that change the magnetic properties to form a latent image according to the optical pattern, and those that scan the material while modulating the brightness and deflecting the light beam to change the magnetic properties by the action of the light beam. There are some that form images.

Magneto-optical materials are materials whose optical properties can be changed by the influence of magnetic fields, light, etc. applied to the materials.
It is made of materials such as AI foundation and MnBi, which have a large change in magnetic permeability and can operate at room temperature. The magnetic latent image referred to here refers to a pattern of changes in optical properties in response to changes in the magnetic field, light, etc.
This change in optical properties varies depending on the material, but is given as a change in the Fuadi effect, in which the plane of deflection of transmitted light rotates, and a change in the Kerr effect, in which the plane of deflection of reflected light rotates. In order to read this change in optical properties as a change in optical density, the entire surface of the material is irradiated with light or a light beam is scanned, and the resulting transmitted or reflected light is observed through a polarizing plate.

In this case, it is necessary to apply a magnetic field to the material at right angles to the incident light on the material, and the magnitude of the applied magnetic field ranges up to 1000 Oersteds, which varies depending on the composition and thickness of the magneto-optical material, but in most cases. is given a magnetic field of 500 oersteds. This magnetic field needs to be applied at the same position as the discussion light beam spot. However, if the magnetic material itself generates a magnetic field through the above-mentioned magnetic port image forming operation, a magnetic field is not necessary when observing changes in optical properties. In the present invention, the gradation image thus read out is transferred to a photosensitive material close to the magnetic material, and a latent image corresponding to the gradation is formed on the photosensitive material.

If the material is a photosensitive material or a photoconductive material, an electrostatic latent image corresponding to the projected image is formed.

This electrostatic port image is developed by applying toner, and if necessary, this visible image is transferred to other copying material to obtain a copy.
The process after transferring the grayscale image to the photoconductive layer is performed by the well-known Carlson or NP type electrophotographic process. Magnetic materials are generally capable of retaining changes in their properties, so the formed latent magnetic image does not disappear.

Therefore, electrostatic images can be repeatedly formed from the same magnetic latent image. If a magnetic material or a photoconductive material is formed into a drum shape and made into a structure in which they touch each other as shown in Figure 1A, or a structure in which they are stacked in a ring shape as shown in Figure 1, a large number of copies can be obtained from the same magnetic latent image. .

In the figure, 1 is an electrostatic port image forming section including a primary corona charger, 2
3 is a developing section, 3 is a transfer charger, and 4 is a roller for cleaning residual toner.

Further, in order to form a new magnetic image on the magnetic material, the magnetic latent image can be erased by the erasing means 9 after being transferred to the photosensitive material.

As the demagnetization means, one of DC demagnetization, AC demagnetization, carry point control, etc. is used. 5 is a magneto-optical material, 6 is a polarizing material, 7
8 is a photoconductive material, and 8 is a conductive substrate.

Magneto-optical materials include MnBi, hexagonal ferrite, rare orthoferrite, rare garnet, rare gadolinium, rare orthochromite, specifically M to Ti.
2Bi, M is Q3, after MnAI, MmGaW, Eu
0,Eu0(Fe),Eship,Enae,CoCr2S,G
GCo, Gdl○, C.

1P-(Ni-Fe), NeFe-PdCo-Co, C
02, Ero. Bumo. 7Fe03, YFe03:C
020, other iron. Dium alloy, Y3Fe5-xSi
Illusion, 2: (YIG), (x neck 5), Y has (Si). In particular, rare earth orthoferrite, rare orthochromite, manganese bismuth alloy, gadolinium iron garnet alloy, and iron rhodium alloy are effective as magneto-optical materials that can be written and erased by operation at room temperature.

Photoconductive materials include zinc oxide, cadmium sulfide, selenium,
Inorganic photoconductive substances such as titanium oxide, and organic light such as polyvinylcarbazole with trinitro or fluorene as a sensitizer, brominated vinylcarbazole polymers, triallyl carbonium salt, benzobylylium salt as a photosensitive component, etc. A conductive material is used.

In the case of the mouth, since the photoconductive material must be transparent, the various photoconductive materials mentioned above, such as cadmium sulfide and polypynylcarbazole, are particularly effective. Figure 4 shows the characteristics of the material and the writing light.

An embodiment based on the method shown in FIG. 2 will be described below.

FIG. 3 shows an example of the apparatus embodying the apparatus shown in FIG. 1-1 is a corona discharger for primary charging the photoconductive material 7, 1-2 is a lamp for illuminating the entire surface of the magnetic material 5, 13 is a roller for feeding the transfer paper 14, and 15 is a corona discharger. Fixing heater,
The other parts are the same as in FIG. The light guide layer 7 is formed on the polarizing plate 6 by coating (coating, vapor deposition, sputtering), and is coated with an insulating layer such as Mylar if necessary. To explain the operation, first, an original optical image is irradiated onto the magnetic material 5 by the forward movement of the document table 10 and the lamp 11, thereby changing the magnetic properties of the magnetic material 5 and thereby changing the optical properties.

At this time, the condition is that the irradiation light has a wavelength that is transmitted through the photoconductive material 7 and absorbed by the magnetic material 5. Scanning with irradiation light from a light beam such as a laser beam can change the magnetic properties and optical properties of the magnetic material due to the thermal energy exerted on the magnetic material and the resulting change in temperature to the Curie temperature. When a magnetic latent image corresponding to the original image is formed by making one revolution of the drum, the primary charger 1-1 is activated to uniformly charge the surface of the photoconductive layer 7. When the charged surface further rotates and reaches the lamp 1-2 for full-surface exposure, the lamp 1-2 is activated to irradiate the magnetic material with light. As a result, a gradation image is obtained which is projected onto the light guide layer 7 via the polarizing plate 6 according to the change in optical properties (the magnitude of the Faraday effect) caused by the change in the magnetic properties formed in the magnetic material, and this gradation light The charges on the photoconducting box layer, which has been primarily charged, are removed in accordance with the above. Deflection plate 6
By making the photoconductive layer 7 conductive, the static eliminator can release the static electricity, and by providing a conductive layer such as Nesa glass between the photoconductive layer 7 and the polarizing plate. The charge pattern is visualized by a liquid developer in the developing device 2, and the toner image is transferred onto a transfer paper 141 fed by a paper feeding roller 13 and thermally fixed by passing through a fixing device 5. The drum is further rotated, residual toner is removed by the cleaning blade 4, and the charger 1-1 lamp 1-2 is turned on again to begin the process of forming a static latent image. This process is repeated to obtain a large number of copies in succession without reciprocating the document table. When forming an electrostatic image, it is also possible to obtain a transmitted light pattern due to the Faraday effect by using a magnetic head that uniformly applies a magnetic field to the magnetic material in the light of the lamp 1-2, if necessary. Since this head is provided at an appropriate distance from the photosensitive drum, there is no reduction in the life of the head or drum due to wear. After the desired number of copies have been made, the erasing head 9 that applies an alternating magnetic field is operated to erase the latent image on the magnetic material. Then, a new magnetic port image is formed on the magnetic material by irradiating the original light and applying a uniform magnetic field as required, and the copying process is performed again. As described above, since the magnetic latent image and the static latent image are formed while rotating the drum, a large number of copies can be obtained from one magnetic latent image. When applying the original light or uniform irradiation light in a magnetic field, it is preferable to irradiate the light through a magnetic head in order to irradiate the irradiation area (slit area, beam point area) of the drum perpendicularly to the direction of the magnetic field. Therefore, the head structure can be simplified by making the roof of the magnetic head transparent. If the original light is applied to the magnetic material 5 from inside the drum and the other processing means remain in place (FIG. 4), it is also possible to apply the simultaneous magnetic field from outside the drum. 20' is a galvanometer mirror that scans the light beam, and 21' is a magnetic head.

In the drum of FIG. 3, if the magnetic material 5 is placed on the outside and the photoconductive layer of the photoconductive material 7 is placed on the inside, and the magnetic material is made of an insulating material such as ferrite, it is possible to provide the uniform light source 1-2 on the outside of the drum. This makes it possible to arrange each processing means on the circumference of the drum.

Further, when forming a magnetic latent image, when a magnetic field is applied to the light irradiation or when the latent image is formed by the magnetic field itself, the edge effect of the image can be reduced and the sensitivity can be increased in the following manner. In other words, when forming a magnetic book image recorded using magnetism, the angle of incidence of the magnetic field lines on the recording medium and the strength of the magnetic field lines vary depending on the structure of the magnetic head, the distance between the magnetic head and the recording medium, and the properties of the magnetic material. The magnetic field is not necessarily applied uniformly because the magnetic field tends to change significantly. As a result, homogeneous magnetism is not applied to the entire magnetized area where the magnetic latent image is to be applied, but rather is biased towards the periphery. Therefore, when a static latent image formed using a magnetic latent image is developed with toner, the image after development is dark at the periphery and thin at the center, a so-called edge effect, which deteriorates the image quality.

Therefore, as shown in FIGS. 5 and 6, strong magnetism is first applied to the magnetic recording medium by the first magnetic head.

After that, the edge effect can be weakened by forming an optical magnetic head that simultaneously inputs a magnetic head or an optical pattern that changes according to external input, so that the polarity is opposite to that of the terminal of the former magnetic head. . When an optical magnetic material is used to cause the magnetic properties, that is, magnetic permeability, of the optical magnetic material to change in accordance with the intensity of the original light pattern, the magnetic properties will be significantly different between the pattern exposed area and the non-exposed area. Generally, the magnetic field in the unexposed area is large and the magnetic field in the exposed area is small. Therefore, the material shown in FIG. 5 may provide a sensitizing effect especially when the magnetic change caused only by light irradiation does not have a sufficient size for development among optical magnetic materials.

In the case of magneto-optical materials, the one shown in Fig. 6 is preferable, as by applying a large magnetic field in advance, rotational development of the deflection surface can be more completely performed on the magneto-optical material, so the size of the magnetic tower image is determined by the application of the magnetic field. It differs markedly depending on the size of the image and increases the contrast. Furthermore, since the size of the magnetic latent image is suppressed by the reverse magnetic field, the edge effect is reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an image forming apparatus according to the present invention, FIG. 2 is a cross-sectional view of an example of an image forming apparatus according to the present invention, FIG. 3 is a schematic cross-sectional view of another example of an image forming apparatus according to the present invention, and FIG. 5 and 6 are cross-sectional views of the magnetic head. In FIG. 1, 5 is a magneto-optical material, 6 is a polarizing plate, 7 is a photoconductive material, 1 is a static exposure latent image forming section, 2 is a developing device, 3 is a transfer roller, and 4 is a cleaning brush. Figure 1 Leopard Figure 2 Figure 4 Figure 5 Strategy Figure 6

Claims (1)

[Scope of Claims] 1. A rotating magnetic material having a magneto-optic effect, means for forming a magnetic latent image on the magnetic material, a rotating electrostatic latent image carrier having a photoconductive material, and the above-mentioned It has a light source that irradiates light onto a magnetic latent image formed on a magnetic material, and a polarizing means that receives the light that has passed through the magnetic latent image, and converts the magnetic latent image into a light density image to carry the electrostatic latent image. An image forming apparatus that includes an optical means for exposing a body to light, and a means for developing an electrostatic latent image formed on an electrostatic latent image carrier by this exposure using toner. 2. The image forming apparatus according to claim 1, wherein the electrostatic latent image carrier is drum-shaped, and the magnetic material is disposed inside the photoconductive material. 3. The image forming apparatus according to claim 1, wherein the electrostatic latent image carrier is drum-shaped, and the magnetic material is also drum-shaped, and is disposed outside the electrostatic latent image carrier. .