JPH03100670A - Image forming method - Google Patents

Abstract

PURPOSE:To allow the stable formation of images over a long period of time by superposing a recording medium on an electrified photoconductive layer and effecting the photoimage irradiation in the state of maintaining the electric charge between this layer and the recording medium, thereby selectively removing the charge between the recording medium and the photoconductive layer and forming latent images. CONSTITUTION:The surface of a photosensitive body 1 formed by laminating the transparent conductive layer 11 and the photoconductive layer 12 on a transparent substrate 10 is electrified by an electrifying means 2 and thereafter, the recording medium P is superposed on the electrified photoconductive layer 12 to hold the charge on the surface of the photoconductive layer 12 between the layer and the recording medium P. The photosensitive body 1 is then exposed by a photoimage exposing means from the transparent substrate 10 side thereof to selectively remove the charge between the photoconductive layer 12 and the recording medium P. The electrostatic latent images on the recording medium P are developed by a developing means 3. The need for making the toner development of the photosensitive body 1 is eliminated in this way and the latent images are stably formed on the recording medium P.

Description

[Detailed description of the invention] [Table of contents] Overview Industrial field of application Prior art (Figure 3) Means for solving the problem to be solved by the invention (Figure 1) Working example (a) 1 DESCRIPTION OF EMBODIMENTS (FIG. 2) (b) DESCRIPTION OF OTHER EMBODIMENTS Effects of the Invention [Summary] This invention relates to an image forming method for forming an image on a recording medium by exposing a photoreceptor to a light image.

The purpose is to form stable images over a long period of time.

After the surface of the photoreceptor, which has a transparent conductive layer and a photoconductive layer laminated on a transparent substrate, is charged by a charging means (secondary charging).

A recording medium is superimposed on the charged photoconductive layer.

retaining the charge on the surface of the photoconductive layer between it and the recording medium;
The transparent substrate side of the photoreceptor is exposed to light by a photoimage exposure means to selectively remove the charge between the photoconductive layer and the recording medium, and the electrostatic latent image on the recording medium is developed by a developing means. develop.

[Industrial application field]

The present invention relates to an image forming method for forming an image on a recording medium by exposing a photoreceptor to a light image.

2. Description of the Related Art Image forming methods in which an image is formed on a recording medium using a photoreceptor are used in various devices such as laser printers, facsimile machines, and copying machines.

In such an image forming method, it is required to be able to form an image stably over a long period of time. [Prior Art] FIG. 3 is an explanatory diagram of the prior art.

3 (Alt=As shown, the surface of the photoreceptor 1, in which a transparent conductive film (layer) 11 and a photoconductive film (layer) 12 such as selenium are laminated on a transparent substrate 10, is connected to a charging power source 21. Uniform charging is performed using a corotron charger 20.

Next, as shown in FIG. 3B, the photoconductive layer 12 is irradiated with a light image using a laser light source or the like to perform exposure corresponding to two image information to form an electrostatic latent image.

Furthermore, as shown in FIG. 3 (q), a developing device (roller) 30
Toner T charged to the same polarity as the --like charge Q by
is electrostatically attached to this electrostatic latent image by an electric field generated by the developing bias 32 to form a toner image.

Thereafter, as shown in FIG. 30, the toner Q on the photoconductive layer 12 is charged on the recording paper P by the transfer power source 41 and the transfer corotron 40, so that the toner Q on the photoconductive layer 12 is charged on the recording paper P by the transfer corotron 40. Toner T is transferred to P.

The toner image transferred onto the recording paper P in this manner is fixed by a fixing device (not shown).

On the other hand, toner remaining on the photoconductive layer 12 is removed by neutralization and cleaning.

[Problem to be solved by the invention]

In such conventional image forming methods, it is difficult to completely remove the toner remaining on the photoconductive layer 12, and when used for a long period of time, the toner adheres to the photoconductive layer 12 and print quality deteriorates. There was a problem.

Also, if two paper jams occur in the recording paper conveyance system.

A large amount of toner adheres to the photoconductive layer, placing a heavy load on recording processes such as cleaning.

There was also the problem that the life of the device was significantly shortened.

Furthermore, since the photoreceptor is rubbed with a developing material or the like, there is a problem that it is easily damaged.

On the other hand, after forming the electrostatic latent image shown in FIG. 3 CB), the electrostatic latent image is transferred onto the recording paper P. A so-called latent image transfer method has also been proposed, but there are problems in that the potential of the electrostatic latent image decreases, the transfer efficiency of the latent image is poor, and stable image formation is difficult.

Therefore, it is an object of the present invention to provide an image forming method that allows stable image formation over a long period of time.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the present invention.

As shown in FIG. 1 (5), the present invention provides a photoreceptor 1 in which a transparent conductive layer 11 and a photoconductive layer 12 are laminated on a transparent substrate 10.
After charging the surface with the charging means 2, as shown in FIG.
A recording medium P is placed on the charged photoconductive layer 12 as shown in FIG. The transparent substrate 10 side of the photoreceptor 1 is exposed by a photoimage exposure means to selectively remove the charges between the photoconductive layer 12 and the recording medium P, as shown in FIG. The electrostatic latent image on the recording medium P is developed by the developing means 3.

[Effect]

In the present invention, the recording medium P is superimposed on the charged photoconductive layer 12, and a light image is irradiated with the charge held between the recording medium P and the photoconductive layer 12. Since the latent image is formed by selectively removing the charges between the two, the latent image can be stably formed on the recording medium P.

Therefore, since it is not necessary to develop the photoreceptor 1 with toner, the problems of developing the photoreceptor 1 with toner can be solved at once, and moreover, a latent image can be stably formed on the recording medium P.

〔Example〕

(a) Description of one embodiment FIG. 2 is a detailed explanatory diagram of the present invention, and shows an electrophotographic printer using LEDs.

In the figure, the same parts as shown in Figures 1 and 3 are:
They are indicated by the same symbols, and 1a is a photoreceptor belt;
As shown in FIG. 1, a transparent conductive layer 11 made of indium oxide is provided on a transparent substrate lo made of polyethylene terephthalate, and a photoconductive layer 12 made of an organic material is further provided on this, and guide rollers 138 to 13d are provided. It is guided by and circulated in the direction of arrow A.

A charger 20 serving as the charging means 2 is provided on the outside of the photoreceptor belt 1a, on the left side surface (between the guide rollers 13a and 13b), and uniformly charges the photoconductive layer 12 of the photoreceptor belt 1a.

The developing device 3 includes a developing roller 30 and a developing bias source 31 (
(see Fig. 1), and supplies toner T to recording paper P to form a toner image.

It is provided on the downstream side of the photoreceptor belt 1a in the recording paper moving direction.

4 is an LED head, which includes a large number of light emitting diodes (LE
D) is provided in the width direction of the photoreceptor belt 1a, is provided inside the photoreceptor belt 1a, and exposes a light image.

Reference numeral 6 denotes a static elimination lamp, which is provided on the outside and right side of the photoconductor drum 1a (between guide rollers 13C and 13d), and uniformly exposes the photoconductive layer 12 of the photoconductor belt 1a to eliminate static electricity. .

50 is a paper cassette that stores paper (recording paper) P, and 51 is a paper feed roller.

ν52, which supplies the recording paper P from the paper cassette 50, is a paper transport belt, which is rotated by a pair of rows 253 and 54, and transfers the supplied recording paper P to a photoreceptor belt)la,
Developing device 3. The image is conveyed to a fixing roller 7, which will be described later. Note that 55 is a counter roller provided opposite to the roller 53.

7 is a fixing roller, which is composed of a heat roller.

facing the roller 54 of the recording paper conveyance belt 52,
The upper toner image is thermally fixed.

The operation of the configuration shown in FIG. 2 will be explained with reference to FIG.

Endless photoconductor bell)la is a guide roller 138
~13d, and the conveyor belt 52 is also circulating in the direction of arrow A.

The photoreceptor belt 1a has a transparent conductive layer 11 like a first country person.
is connected to the ground side and the charger 20 is connected to the positive side by the charging power source 21, and is uniformly charged by the photoconductive type positive charge Q.

In parallel with this operation, by the paper feed row 251.

Recording paper 'P is supplied from a paper cassette 50 and transported by a transport belt 52.

As a result of these operations (2), the recording paper P is sandwiched between the photoreceptor bell (la) and the conveyor belt 52 as shown in FIG. As shown in (B), the charge on the surface of the photoreceptor belt 13 continues to be held between the photoreceptor belt ()la and the recording paper P.

Next, using the I/ED head 20, a light image is irradiated from the transparent substrate 10 side of the photoreceptor belt 1a according to the two-image pattern as shown in FIG. 1(q).

As a result, the photoconductive layer 12 of the photoreceptor belt (1a) irradiated with light is separated from the photoreceptor belt (1a) and the recording paper (P) by the photoconductive effect.
An electrostatic latent image is formed between the photoreceptor belt 1a and the recording paper P.

This electrostatic latent image reaches the developing device 3 as the recording paper P moves. In the developing device 3, as shown in FIG. 1(2), the conveyor belt 52 is grounded, and a positive potential is applied to the developing roller 301 by the developing bias source 31.

A positive donor T is supplied by the electric field to form a toner image. This toner image is fixed by a fixing roller.

Further, the charge remaining on the photoconductor bell (1a) is removed by light irradiation (secondary) from the charge eliminating lamp 6, and by repeating this series of steps, image formation is performed continuously.

In this embodiment, since the photoreceptor is in the form of a belt, the recording paper P can be sufficiently sandwiched between the conveyor belt 52 and the electric charge of the photoreceptor belt (la) can be sufficiently retained between it and the recording paper P. This can contribute to stable latent image formation.

Furthermore, since the LED head 4 is provided inside the photoreceptor bell (la), it also contributes to miniaturization of the apparatus.

(b) Description of other embodiments In the above-described embodiments, the photoreceptor L is in the form of a belt, but it may also be in the form of a drum. In this case, the recording paper P is transported so as to be wrapped around a part of the drum. .

It is necessary to maintain charge between the photoreceptor 1 and the recording paper P.

Furthermore, the light image irradiation means is not limited to the LED head.

Well-known devices such as a liquid crystal shutter type and a laser scanning type can be used.

Although the present invention has been described above using examples, the present invention can be modified in various ways according to the gist of the present invention.

These are not excluded from the present invention.

〔Effect of the invention〕

As explained above, according to the present invention.

■ Since toner is not developed on the photoconductor, it is possible to prevent the photoconductor from becoming smudged or stuck, and there is no need to clean the photoconductor, and damage to the photoconductor is reduced, allowing for long-term use. This has the effect of

(2) Also, when forming a latent image on a recording medium, an electric charge is held between the photoreceptor and the recording medium.

Since a light image is irradiated, charges are sufficiently attached to form a latent image with sufficient potential, and the latent image can be stably formed.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle of the present invention. FIG. 2 is a detailed explanatory diagram of the present invention. FIG. 3 is an explanatory diagram of the prior art. In the figure, 1...photoreceptor. 2... Charging means. 3...Developing means. 10...Transparent substrate. 11...Transparent conductive layer. 12... Photoconductive layer. P...Recording medium. Next door [

Claims (1)

[Claims] Charging means (2) charges the surface of a photoreceptor (1) in which a transparent conductive layer (11) and a photoconductive layer (12) are laminated on a transparent substrate (10).
), a recording medium (P) is superimposed on the charged photoconductive layer (12), and the charge on the surface of the photoconductive layer (12) is transferred to the recording medium (P).
The photoconductive layer (12) and the recording medium (P) are exposed to light from the transparent substrate (10) side of the photoreceptor (1) by a photoimage exposure means.
An image forming method comprising: selectively removing charges between the recording medium (P) and developing the electrostatic latent image on the recording medium (P) by a developing means (3).