JPS62257186A - Electrostatic recording device - Google Patents

Abstract

PURPOSE:To prevent paper powdery, components of paper, etc., from sticking and to suppress the generation of an image run on transfer paper by forming a toner image part at a no-image part which precedes a transfer image part on a photosensitive body corresponding to a paper feeding means. CONSTITUTION:At the no-image part which precedes the transfer image part 101 where transfer from the photosensitive body 10 is carried out, a toner image is formed at the part, i.e. position corresponding to a paper feed roller 31, etc., so that a part on the photosensitive body 10 where paper powder and components of paper stick specially much is rubbed and polished. In general, toner contains external additives such as abrasive silica, so a cleaning blade and a cleaning roller as a cleaning means rubs and polishes the surface of the photosensitive body 10 as well as cleaning if toner is interposed on the photosensitive body 10. Consequently, an excellent image copy is obtained which is free of image defocusing and an image flow for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrostatic recording device that forms a toner image on an electrophotographic photoreceptor and transfers and fixes the toner image onto a transfer paper.

[Conventional technology]

A transferable image (toner image) of toner is formed on the surface of a rotating and moving electrophotographic photoreceptor, and residual toner remaining on the surface of the photoreceptor after the toner image is transferred onto transfer paper;
Fine pieces of paper generated from the transfer paper and attached to the surface of the photoreceptor,
In an electrostatic recording device in which foreign matter such as rosin, talc, etc. deposited from transfer paper or corona products produced by high voltage generating members during the first image forming process are removed, the electrophotographic photoreceptor can be used repeatedly. In order to obtain high-quality hard copies, it is essential that a cleaning section provided at the peripheral edge of the photoreceptor drum completely remove residual toner and foreign matter. As a cleaning means for this purpose, it has been proposed and put into practice to use a cleaning blade, fur brush, web, etc. to rub the surface of the photoreceptor. Although these cleaning/cleaning methods in practical use are sufficiently satisfactory in removing residual toner, they are insufficient in removing fine paper particles, rosin, talc, etc. that are generated and deposited from transfer paper. That was enough.

This tendency is due to the fact that the photoreceptor is an organic photoconductor (OPC) and
This was especially true in cases of high temperature and high humidity. If such substances are not removed from the photoreceptor by the cleaning means and adhere to the surface of the photoreceptor, especially in high humidity conditions, they will absorb water and become low in resistance, resulting in blurred and washed out images and a significant reduction in copy image quality. It was something to do.

The present inventors have discovered that paper dust and paper components that cause image deletion do not adhere uniformly on the photoreceptor in the direction perpendicular to the feeding direction of the transfer paper;
It has been found that the paper feed roller or "C" which conveys the sheet of transfer paper repeatedly adheres to the separation belt or the like at a position corresponding to the portion where the transfer paper is rubbed. Therefore, when image deletion occurs on the transfer paper, the position corresponds to the paper feed roller position, and as dozens of copies are made, the adhesion gradually increases and image deletion occurs at the above location on the transfer paper. Something happened.

Conventionally, as a countermeasure against this problem, a heater was installed in the device to lower the relative humidity inside the device to prevent paper dust and paper components from adhering to the photoreceptor, and Japanese Patent Application Laid-open No. 112084/1984 As proposed in 2003, special leaning rollers have been provided to prevent adhesion.

[Problems to be Solved by the Invention] The present invention prevents the adhesion of paper powder, paper components, etc. to the photoreceptor portion without requiring any special equipment, and prevents the adhesion of paper dust and paper components onto the transfer paper. An object of the present invention is to provide an electrostatic recording device that suppresses the occurrence of image deletion.

[Means for solving the problem] The above purpose is to form a toner image area in a non-image area preceding a transfer image area on a photoreceptor corresponding to a paper feeding means that feeds transfer paper. This is achieved by a characteristic electrostatic recording device.

[For production]

Toner generally contains external additives such as abrasive silica, so when toner is present on the photoreceptor, the cleaning blade or cleaning roller used as a cleaning means scrubs and polishes the surface of the photoreceptor while cleaning. It has an effect. On the other hand, paper powder/paper components adhere to the surface of the photoreceptor, and the adhesion to the surface of the photoreceptor is particularly noticeable on OPC photoreceptors.

The polishing effect of the toner mentioned above and the adhesion of paper powder and paper components on the OPC photoreceptor are extremely small effects, and even under high humidity, if continuous copying is performed for about 3,000 copies, the above effect will occur. is only slightly noticeable. Therefore, the present invention is designed to effectively rub and polish the areas on the photoreceptor where paper dust and paper components are particularly attached, in the non-image area preceding the transferred image area on the photoreceptor. , a toner image is formed at that portion, that is, at a position corresponding to the paper feed roller or the like.

Even when copying is performed, the toner image is not transferred to the transfer paper, so it is supplied as it is to the pressure contact part of the cleaning blade or cleaning roller, and the toner is swept away by the cleaning means and effectively transferred to the photoreceptor. The surface will be rubbed and polished. The present invention prevents paper powder and paper components from adhering to the surface of the photoreceptor through this rubbing and abrasive action.

〔Example〕

FIG. 1 is an electrostatic recording apparatus showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the positional relationship of toner image areas, etc. according to the present invention.

First, a general explanation of the electrostatic recording apparatus will be given with reference to FIG.

There is a charging electrode 11 on the periphery of the photoreceptor drum 100 that rotates in the direction of the arrow to uniformly charge the surface of the photoreceptor.
There is an optical system 12 configured to form an image of a document placed thereon onto a photoreceptor 10 . The uniformly charged photoreceptor 10 forms a latent image by imagewise exposure.

13, an ID array consisting of a large number of elements is connected to the photosensitive drum 1;
An image frame forming section provided parallel to the axial direction of the photoreceptor 10 irradiates the area other than the image area to be transferred by the control section.
Remove the charge on top.

1. The latent image on the photosensitive drum 10 is developed by the developing device 1. By development, toner adheres to the charged latent image portion on the photoreceptor lO, forming a toner image.

On the other hand, the cassette 30 containing many sheets of transfer paper P is
The toner images on the photoreceptor 10 are transferred onto the transfer paper P by the transfer poles 15 after contacting the photoreceptor drum 10. A transcription is made. The transfer paper P having the toner image is transferred to the photoreceptor drum 10 by the separating section 1G.
The paper is separated, fixed by the fixing device 33, and then discharged from the device.

After completing the transfer process, the photosensitive drum 10 is cleaned of residual toner by a cleaning means 17 such as a cleaning blade or a cleaning roller.

FIG. 2 shows the transfer paper P, the paper feed roller 3I that separates and conveys the transfer paper P by squeezing it one by one, the transfer unit that transfers the image to the transfer paper P on the surface of the developed photosensitive drum 10, and the transfer FIG. 4 is an explanatory diagram showing the positional relationship of a toner image portion formed in a non-image area preceding the toner image portion according to the present invention.

This toner image area is formed on the photoreceptor 10 by providing a black frame plate 22 at the tip of the document table 21 shown in FIG.
A latent image of the toner image area can be formed on the photoconductor lO, or it can be formed by stopping the irradiation of a part of the image frame forming section 13 that irradiates the outside of the transferred image area on the photoreceptor lO with the LED array. can.

The toner image area 102 is formed at a position corresponding to the paper feed roller 31 preceding the transfer image area 101.
The toner image area 102 was set at an interval of about 5 mm ahead of the transferred image area 101, slightly wider than the paper feed roller 31 in the width direction, and had a length of about 10 mm in the direction of photoreceptor movement.

The present inventors conducted a comparative test on the case where the above-mentioned toner image area was formed and the case where the toner image area was not formed. Regarding the photoreceptor, the applicant filed a patent application in 1982-5.
9423 to Japanese Patent Application No. 58-59425, or Japanese Patent Application No. 59-171741 to Japanese Patent Application No. 59-17174
Although many OPC photoreceptors have been disclosed in Japanese Patent No. 7, etc., tests were conducted on general OPC photoreceptors.

Continuous copying of 5,000 sheets was carried out using Al1 size transfer paper at a room temperature of 33° C. and a relative humidity of 80%. As a result, when a toner image area was not formed, blurring and image deletion were observed on the transfer paper at a location corresponding to the paper feed roller after about 1,4000 sheets. On the other hand, when a toner image area was formed, no change was observed even after copying 50υO sheets.

As described above, the effect of forming a toner image area has become clear. As is well known, the reflection density of the toner image area can be measured and used as an information source for setting development conditions and toner replenishment, so the toner image area according to the present invention can be used in combination with such information sources. It is also possible.

[Effects of the Invention] According to the present invention, an electrostatic recording device capable of producing good image copies without image blurring or image deletion over a long period of time can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an outline of an electrostatic recording apparatus to which the present invention is applied, and FIG. 2 is an explanatory diagram showing the positional relationship of toner image areas, etc. according to the present invention. 20...Photoreceptor (drum) 11...Charging electrode 13...
・Image frame forming part n...Black frame plate 31...Paper feed roller 101...Transfer image part 102...Toner image part P...Transfer paper applicant Konishiroku Photo Industry Co., Ltd. Figure 2

Claims (2)

[Claims] (1) An electrostatic recording device characterized in that a toner image area is formed in a non-image area preceding a transfer image area on a photoreceptor, which corresponds to a paper feeding means for feeding transfer paper. (2) The electrostatic recording device according to claim 1, wherein the photoreceptor is an organic photoconductor.