JPH05165300A - Color image recording method - Google Patents

Abstract

PURPOSE:To enable image recording with a simple stage and simple device by exposing the conductive color toners applied on photosensitive member according to image data and transferring the color toners through which light is transmitted to image recording paper by a pressure. CONSTITUTION:The conductive color toners 3 to 5 having light transmittability are applied in one layer onto zinc oxide paper 1 which is the photosensitive member electrified to minus by a primary electrifier. The zinc oxide paper 1, then, receives the exposing light 2 according to the image, by which the color toners are divided to the yellow and magenta toners 3, 4 to allow the transmission of the wavelength of the exposing light 2 and the cyan toner 5 to prohibit the transmission of this wavelength. The potential of the zinc oxide paper 1 under the exposed parts of the toners 3, 4 is decreased and the electrostatic attraction between the toner photosensitive bodies is substantially eliminated. The zinc oxide paper 1 with its toner sticking surface directed downward is placed on the recording paper 7 and is squeezed in a direction 9 by applying a pressure toward an arrow 8, by which the toners 3, 4 of the exposed parts are transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color printer, and more particularly to an image recording method for a one-shot color printer using a conductive color toner.

[0002]

2. Description of the Related Art In the present information society, copying machines, printers and the like are commercially available as color image forming apparatuses as means for easily and accurately transmitting the information. There is a demand for a color image forming apparatus that can print more easily, more finely, cheaper, and faster. In order to meet this demand, a color image forming apparatus using an electrophotographic system has been proposed. There are two types of methods, a multi-process method and a one-shot method. The need for a large-diameter drum, which was a drawback of the multi-process method, has already been solved by increasing the number of drums, and it has been commercially available. However, the problem of high-precision mechanical alignment mechanism associated with overlay still remains, which is a drawback that makes the device heavy and expensive.

On the other hand, the one-shot color system which does not require superposition is, for example, Japanese Patent Publication No. 55-273.
No. 41, a method of using a special color toner, and JP-A No. 63-285566, a method of obtaining a color print by combining three color toners are disclosed. However, in these methods, it was necessary to solve the problems caused by the special toner and the lack of expression colors.

A method for obtaining a color print is disclosed in Japanese Patent Application No. 2-263878 as a one-shot color system which solves the problems of these methods. This is a method for obtaining a color print by the method described below. The electrophotographic photosensitive member 13 of FIG. 3 uses an organic photo semiconductor having sensitivity to red light, green light, and blue light. The surface of the electrophotographic photosensitive member is charged and cyan toner C that transmits blue light and green light and absorbs red light, magenta toner M that transmits blue light and red light and absorbs green light, and transmits green light and red light. The yellow toner Y that absorbs blue light is uniformly applied to each layer in each color. By using the exposure light 14 in which the intensity of red light IR, the intensity of green light IG, and the intensity of blue light IB are adjusted according to the image,
The color toner on the photoconductor and the electrostatic force of the photoconductor are reduced to select and transfer the image to the recording paper. At this time, the relationship between the exposure light and the peeling or transfer toner is as shown in Table 1 on the next page.

A known method for further layering is to use a conductive color toner. When using the one-shot color method that does not require downsizing of the image forming apparatus and precision of superposition, further improvement is an important issue.
It is known that the use of conductive color toner is easy. A printer using a toner having a high electric conductivity, which has a very low resistance to a conventional insulating toner, has already been produced. However, coated paper and insulating coated paper have been mainly used as image recording paper for printers using conductive color toner. This is because the transferred image on the plain paper is blurred by the conventional transfer method using corona discharge.

[0006]

As described above, the one-shot color system which does not require superposition has a problem in transfer onto plain paper or the like. SUMMARY OF THE INVENTION It is an object of the present invention to provide an image recording method which solves such a problem and which can be performed by a simple process and a simple device.

[0007]

In order to achieve the above-mentioned object, the present invention further coats a photosensitive member with conductive color toners of a plurality of colors that selectively transmit light depending on the wavelength of exposure light to form an image. After exposing the color toner according to the data,
The toner is characterized in that a transfer image is obtained by utilizing the pressure of the toner, which transmits the light and loses the electrostatic attraction between itself and the photoconductor, without using the electrostatic force of the corona discharge or the electrodes.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1A shows a zinc oxide paper 1 which is a photosensitive member which is negatively charged by a primary charger, and a conductive color toner which is one layer coated on the zinc oxide paper. In addition, the conductive color toner is a light-transmitting color toner, where Y is yellow toner 3, M is magenta toner 4, and C is cyan toner 5. Although the toner is drawn like a true spherical toner in the drawing for the sake of convenience, the toner need not necessarily be a true sphere. At this point, the zinc oxide paper is negatively charged, and the conductive color toner is attached to the surface by induction charging. These operations are performed in the dark so that the surface potential of the zinc oxide paper does not drop. At this time, even if the toner-adhering surface faces downward, the layered toner does not drop.

FIG. 1B shows the zinc oxide paper 1 which has received exposure light corresponding to an image. Arrow 2 indicates exposure light.
As an example, the exposure light used here is 2 × IR. Depending on the wavelength of the exposure light, the color toner is divided into yellow and magenta toners 3 and 4 that transmit the wavelength and cyan toner 5 that does not transmit the wavelength. Since the toners 3 and 4 transmit this wavelength of the exposure light, the electric potential of the zinc oxide paper under the exposed portion is reduced, and the electrostatic attraction between the toner and the photoconductor is almost eliminated. The toner 6 in the non-exposed area and the cyan toner 5 that does not transmit the exposure light are electrostatically attached to the surface of the zinc oxide paper without reducing the surface potential of the zinc oxide paper.

After the exposure is finished, the zinc oxide paper 1 is placed on the recording paper 7 with the toner adhering surface facing downward as shown in FIG. 1 (c). To do it easily, apply pressure in the direction of arrow 8
When the zinc oxide paper is removed after squeezing in the direction indicated by (3), only the toners 3 and 4 which are the toner of the exposed portion and which transmit the wavelength of the exposure light are transferred onto the recording paper. here,
The recording paper 7 is plain paper, and the plain paper is placed on a table. The pressure may be applied either from above or below, and the movement may be on the pressure side, the photoconductor, or the recording paper side.

FIG. 2 shows a device in which the above process is simplified. Here, a metal roller 10 and a rubber roller 11 are used to apply pressure. A pressure is applied between the two rollers by a spring, and at the same time, it serves to convey the zinc oxide paper 1 which is a photoconductor and the recording paper 7 which is a plain paper. The arrows in the metal roller 10 and the rubber roller 11 indicate the rotation direction of each roller. 12 is a paper tray. The above process is performed in the dark.

[0012]

As described above, according to the color image recording method of the present invention, the conductive color toner can be easily transferred, and the transferred image can be obtained even on the plain paper. Further, since the transfer process does not depend on electrostatic force such as corona discharge, a power source for transfer is not required, and it is effective in downsizing and weight saving of the image forming apparatus.

[Brief description of drawings]

FIG. 1 is a process diagram of an image recording method of the present invention.

FIG. 2 is a schematic view of a main part of an image recording apparatus using the method of the present invention.

FIG. 3 is an explanatory diagram of image recording by a conventional one-shot color system.

[Explanation of symbols]

 1 Zinc Oxide Paper 2 Exposure Light 3 Yellow Toner 4 Magenta Toner 5 Cyan Toner 6 Conductive Color Toner of Unexposed Area 7 Recording Paper (plain paper) 8 Direction to Apply Pressing Force 9 Direction to Rub Pressing Force 10 Metal Roller 11 Rubber roller 12 Paper tray 13 Photoconductor 14 Exposure light

Claims (1)

[Claims] 1. A conductive color toner of a plurality of colors that selectively transmits light is coated on a photosensitive member in one layer, and the color toner is exposed according to image data, and the color toner through which the light is transmitted, A color image recording method characterized in that the image is transferred onto an image recording paper by pressure.