JPS62261457A - Static recorder - Google Patents

Abstract

PURPOSE:To prevent a decrease in the potential of a latent image and latent image unevenness without provision of a special heating means by holding an area including a latent image carrier and a recording head airtight and dehumidifying the atmosphere of said area. CONSTITUTION:A static latent image device is surrounded with an airtight wall 17, and paper to be supplied to a transfer part is fed to a feeder roll 11 through a flexible auxiliary airtight member 25. If paper is discharged from a fixing vessel 12 after completion of undergoing a transfer process, it is then discharged from an auxiliary airtight member 26. A dehumidifying means 18 is provided inside the airtight wall 17, and a fan 19 and a dehumidifying agent 20 are stored in the dehumidifying means 18. This design enables elimination of the degradation of a recording image due to environmental change, especially image defects due to the lowering of discharge efficiency and abnormal discharge when the humidity is high. Further, if the properties of a latent image carrier 1 itself deteriorate, a stable recording image can be obtained provided that the deterioration falls within a certain range.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrostatic recording device for recording images used in printers, facsimiles, and the like.

What is an image recording device using conventional technology electrophotography? An electrostatic latent image is formed on an image carrier, and this electrostatic latent image is visualized using a developer, and many image recording apparatuses of this type are in widespread use. Further, as disclosed in U.S. Pat. No. 4.155.093, a dielectric material is used as the latent image bearing drum,
2. Description of the Related Art There is known an electrostatic recording device that forms an electrostatic latent image on a latent image carrier drum by emitting ions due to discharge.

In this method, ions generated by an ion-emitting recording head are controlled by an image signal from an image signal source, and an electrostatic latent image corresponding to the image signal is formed on a latent image carrier drum.

The dielectric material on the surface of the latent image carrier is made of materials such as resins, metal oxides, and ceramics, but all of these materials are highly dependent on the environment such as humidity and temperature, and the latent image may deteriorate, especially in high humidity. There is a tendency that the surface resistance and volume resistance of the carrier tend to decrease.

Problems to be Solved by the Invention When the surface resistance or volume resistance of the latent image carrier decreases, the W3 image potential decreases, latent image unevenness occurs, and a good recorded image cannot be obtained. In order to solve these conventional problems, a method of heating the latent image carrier and a method of heating the vicinity of the discharge position of the recording head (Japanese Patent Laid-Open No. 60-7968
No. 9) etc. have been proposed.

However, electrostatic recording devices that use this conventional heating method are equipped with a heat source inside the device in order to stabilize the surface resistance and volume resistance of the latent image carrier. There is a problem in that it causes an adverse effect on the developer, for example, the same property of the developer and coagulation.

The purpose of the present invention is to solve these problems, that is, to provide a submerged heating system without providing any special heating means. !
The objective is to form a recorded image that does not cause potential drop or latent image unevenness.

Means for Solving the Problems In order to achieve the above object, the electrostatic recording device of the present invention includes:
a latent image carrier having a dielectric thin film layer on its surface; a recording head that faces the latent image carrier and forms an electrostatic latent image on the latent image carrier according to an image signal; and at least the latent image carrier. and a dehumidifying means for dehumidifying the atmosphere in the area.

According to the present invention, since the area including at least the latent image carrier and the recording head is dehumidified by the dehumidifying means, the electrostatic recording apparatus is not affected by environmental changes such as temperature changes and humidity changes. A stable electrostatic latent image can be formed on the latent image carrier by the recording head.

Example Embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the schematic structure of one embodiment, and FIG. 2 shows the peripheral portion of the recording head.

The recording head 2 controls the ions generated by the corotron 4 using the control electrode 5 according to the image No. 45 output from the image signal source 6, and releases the ions to the latent image carrier 1 itself, thereby printing the latent image. A predetermined electrostatic latent image is formed on the carrier 1.

The electrostatic latent image on the latent image carrier 1 is developed by a developing device 7,
These developed images are transferred by the transfer corotron 8 to the paper fed from the feed roll 11, and the transferred image is transferred to the fixing device 1.
Fixed in 2. The developer remaining on the latent image carrier 1 is
The latent image bearing member 1 that has been scraped off by the blade cleaner 13 and then cleaned is neutralized by the static eliminator L1 tron 24 in preparation for the next recording cycle.

As shown in FIG. 1, the components of the electrostatic latent image 5A are surrounded by an airtight wall 17 and kept airtight from the outside air. The material for the airtight wall 17 may be any material that does not have air permeability, such as metal or resin. The paper supplied to the transfer section passes through the flexible airtight auxiliary member 25 and passes through the feed roll 11.
After the transfer is completed and the image is ejected from the fixing device 12, the image is ejected from the airtight auxiliary member 26 to an ejection tray (not shown). It is desirable that the airtight reinforcing members 25 and 26 be made of resin such as rubber film, and treated to be electrically conductive so as to prevent frictional charging with the paper.

A dehumidifying means 18 is provided inside the airtight wall 17, and a fan 19 and a moisture absorbent 20 are stored inside the dehumidifying means 18. The moisture absorbent uses a desiccant agent such as silica gel to dehumidify the inside of the airtight wall 17. ? The fan 19 is rotated at a predetermined time to keep the ambient humidity constant.

By doing this, deterioration of recorded images due to environmental changes,
Especially high school students! It is possible to eliminate image defects caused by a decrease in discharge efficiency, abnormal discharge, etc. at the time of ii1, and even if the characteristics of the latent image carrier 1 itself deteriorates, it can be stabilized to a certain extent by the moisture absorption function of the dehumidifying means 18. A recorded image can be obtained.

In general, the relationship between the humidity around the latent image forming area and the upper layer of the latent image is as shown in FIG. 4, and as the humidity increases, the latent image potential relatively decreases. By keeping the humidity within a predetermined range, the latent potential of the electrostatic latent image formed on the latent image carrier 1 is kept almost constant, resulting in a stable recorded image that is not affected by the external environment. can be formed.

FIG. 3 shows the main part of another embodiment of the present invention, in which the dehumidifying means is controlled according to the output signals of two types of humidity sensors.
211.

When the airtight wall humidity sensor 30 provided inside the airtight wall 17 detects that the humidity is above a predetermined humidity, the valve opening/closing circuit 33 is driven by a command from the control circuit 32 and the circulating air discharge valve 26 is closed. Together with 2! (iii) The wind discharge valve 27 is opened, the power source 35 drives the heater 28 in response to a command from the heater control circuit 34, and the fan 19 is rotated to vaporize the moisture contained in the moisture absorbent 20 and remove this wet air. is discharged to the outside from the damp air discharge valve 27.

Next, when it is detected by the dehumidifying means humidity sensor 31 that the humidity inside the dehumidifying means 18 has decreased below a predetermined value, it is assumed that the moisture absorbent 20 has dried, and the control circuit 32
In response to the command, the circulating air discharge valve 26 is heard and the MJII discharge valve 27 is closed, and the heater 28 is stopped in response to the command of the heater control circuit 34, and the air inside the airtight wall 17 is dehumidified by the rotation of the fan 19. By taking in the moisture absorbent 2 into the circulation 7M discharge valve 26,
0 to dehumidify the inside of the airtight wall 17.

The moisture absorbent 20 absorbs moisture, and the humidity sensor 31 as a dehumidifying means
When the humidity is again detected to be higher than the predetermined value, the above operation is repeated to keep the smallpox inside the airtight wall 17 within a constant range at all times.

In this way, the humidity inside the airtight wall 17 is kept within a certain range, so the ion recording output by the recording head 2 is stabilized, and the electrostatic latent image on the latent image carrier 1 is reduced to image defects such as humidity unevenness. This results in stable electrostatically recorded images with no blemishes. Furthermore, since no special heating means is provided, power consumption can be saved.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, at least the area including the latent image carrier and the recording head is kept airtight and the atmosphere in this area is dehumidified, so that the area is not affected by the external environment. Therefore, when performing D main recording, a stable recorded image with good reproducibility and less environmental dependence can be formed.

Further, according to the present invention, since the latent image carrier, the recording head, etc. can be used in a stable environment, the selection range of materials used for the dielectric a film layer provided on the surface of the latent image carrier is expanded. By using a suitable dielectric thin film material, an electrostatic recording device can be manufactured at low manufacturing cost.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and FIG. 2 is a diagram showing the peripheral area of the recording head. FIG. 3 is a schematic diagram showing another embodiment of the present invention, and FIG. 4 is a graph showing the relationship between the humidity around the latent image forming part and the latent image potential. DESCRIPTION OF SYMBOLS 1...Latent image carrier, 2... Recording head, 11
... Co[] Totrolone 5... Control electrode, 6.
...Image signal source, 7.Developing device, 8.Transfer corotron, 18.Dehumidifying means, 19.Fan, 20.Moisture absorbent.

Claims (1)

[Claims] Electrostatic recording comprising a latent image carrier having a dielectric thin film layer on its surface, and a recording head facing the latent image carrier and forming an electrostatic latent image on the latent image carrier according to an image signal. In the device,
An electrostatic recording apparatus comprising: an airtight maintaining means for keeping an area including at least a latent image carrier and a recording head airtight; and a dehumidifying means for dehumidifying the atmosphere in the area.