JPH10198124A - Electrifier and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an electrifier reduced in cost and capable of suppressing the in-plane dispersion of the temperature of a substrate by heating the substrate to enhance discharge efficiency and incorporating a heating means for decomposing ozone. SOLUTION: This electrifier for electrifying an image carrier by creeping corona discharge incorporates the heating means 70 for the substrate around an exciting electrode 40(40a, 40b, 40c and 40d). The heating means 70 forms an electrode for heating by an electrode forming stage where it forms the electrode with the electrode 40 on the same substrate simultaneously, whereby the number of parts is reduced. The heating means 70 for the substrate 11 is disposed in a low-temperature area on the substrate 11 with high density. Namely, it is disposed at the end part 10B in the longitudinal direction of the substrate so as to constitute a wiring with high density.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device used to charge an image carrier such as a photoreceptor in an electrophotographic apparatus such as a copying machine or a printer, and more particularly to a device for decomposing ozone generated during charging. The present invention relates to a device which is provided with a heating means for reducing the cost by incorporating the heating means.

[0002]

2. Description of the Related Art In JP-A-54-53537 and JP-A-59-44797, a linear discharge electrode is provided on the surface of an alumina substrate, and a planar excitation electrode is embedded inside the substrate. There is disclosed a creeping corona discharge element in which a linear discharge electrode and a planar excitation electrode are arranged to face each other with a dielectric interposed therebetween. Japanese Patent Application Laid-Open No. Sho 60-79689 discloses a configuration in which the vicinity of a discharge region of a creeping corona discharge element is heated to decompose ozone.

[0003]

Conventionally, in an electrophotographic apparatus such as a copying machine or a printer, various charging devices have been used for charging an image carrier such as a photoconductor to form an image. I have. For example, as an apparatus for charging an image carrier such as a photoconductor, (1) a photoconductor is charged by corona discharge using a corotron charger or a scorotron charger. (2) Creeping corona discharge is carried out by a creeping corona discharge by a creeping discharge element of a linear excitation electrode provided on the surface of the alumina substrate and a planar discharge electrode buried opposite to each other via a dielectric to charge the photosensitive member. Etc.

Here, the charging device (2) will be described with reference to the drawings (see FIG. 7). Linear excitation electrode 4 on substrate 1
(A, b, c, d) are formed by thick film printing. Alternatively, after forming a dielectric layer by means such as sputtering, the excitation electrode 4 is formed by patterning by photolithographic etching. The excitation electrode 4 is connected to a power supply 5.
Further, the discharge electrode 3 connected to the power supply 5 via the dielectric 2 is formed by the same means as the excitation electrode 4 to form a surface discharge element. Further, for example, a silicon rubber-like heater (not shown) is attached to the back surface of the creeping discharge element to form a charging device.

In the above-described charging device and surface corona discharge element, the generation of nitrogen oxides and ozone adversely affects the human body and the environment. In a photographic apparatus or the like, there has been a problem that ozone floating in the apparatus peels off an external additive adhering to toner and forms an insulating film on a photoreceptor to affect an image. As a means for solving these problems, conventionally, an ozone filter has been used to forcibly discharge nitrogen oxides and ozone inside an electrophotographic apparatus such as a copying machine or a printer. However, this was not completely solved, and the problem had not been solved.

[0006] On the other hand, as a known technique, a charging device that attaches, for example, a silicon rubber-shaped heater to the back of a substrate of a creeping corona discharge element and heats the substrate 1 to increase discharge efficiency and decompose ozone is known. is there. However, application of this technology to electrophotographic devices such as copiers and printers has the problems of increasing the number of parts, leading to increased costs, and preventing the entire substrate from reaching the set temperature.

Accordingly, the present invention relates to a charging device configured to charge an image carrier such as a photoreceptor and heat a substrate to increase discharge efficiency in an electrophotographic device such as a copying machine or a printer. It is an object of the present invention to reduce the cost by incorporating a heating means for decomposing ozone and at the same time to suppress the in-plane variation of the substrate temperature.

[0008]

A charging device for charging an image carrier by creeping corona discharge according to the present invention has a structure in which a heating means for a substrate is built in around an excitation electrode. This charging device has a configuration in which an electrode for heating is formed on the same surface as the excitation electrode to reduce the number of parts. The means for heating the substrate is arranged at a high density in a low-temperature region of the substrate, that is, a high-density wiring is provided at the longitudinal end of the substrate.

The method of manufacturing a charging device according to the present invention includes an electrode forming step of simultaneously forming a linear excitation electrode and a linear heating electrode disposed close to the excitation electrode on the same substrate; The method includes a dielectric layer forming step of forming a dielectric layer on the substrate on which the excitation electrode and the linear heating electrode are formed, and a discharge electrode forming step of forming a discharge electrode at a position on the dielectric layer corresponding to the excitation electrode. In this method of manufacturing a charging device, a heating electrode is formed on the same surface as an excitation electrode by the same process, thereby reducing the number of components and simplifying the process.

Here, the two electrode shapes are formed simultaneously by a thin film method in which an Au film is formed by using a thick film printing method or sputtering and patterned by photolithographic etching.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a schematic plan view showing the overall configuration of the charging device, FIG. 2 is a schematic cross-sectional view taken along line AA of FIG.
FIG. 3 is a plan view of a discharging portion for charging. Charging device 10
Are located at predetermined positions on the alumina substrate 11.
0 (a, b, c, d) and the heating electrode 70 are formed.
The electrodes 40 and 70 are formed by a thick film printing method.
A u film is formed on the alumina substrate 11, or a heating electrode 70 is pattern-formed so as to surround four linear discharge dielectric electrodes 40 near the electrode 40 in the center of the substrate 11 by photolithographic etching. I do.

The dielectric layer 20 is formed on the excitation electrode 40 and the heating electrode 70. The dielectric layer 20 has a low dielectric constant. Further, a discharge electrode 50 is formed on the dielectric layer 20. The discharge electrode 50 is formed by patterning a Ni or LaB6 film at a position corresponding to the excitation electrode 40 by a thick film method. The protection layer 30 is formed on the discharge electrode 50.

The protective layer 30 is formed by opening a window 35 so that a part of the discharge electrode 50 is exposed. The excitation electrode 40 and the discharge electrode 50 are connected to a high-voltage power supply 60, and the heating electrode 70 is connected to an electrode 80. Here, the conductive film for forming the excitation electrode 40 and the heating electrode 70 is formed of chromium, copper, tungsten, aluminum, platinum,
Conductivity such as titanium may be formed by a method such as sputtering, and may be patterned by photolithographic etching.

As described above, the charging device 10 has the four linear excitation electrodes 40 at the center and the heating electrodes 70 disposed in the vicinity of the excitation electrodes 40. The formation of each electrode is performed by a separate process. Are formed at the same time by using a thick film printing method, a sputtering method, or the like without using a thin film. The charging device 10 thus formed is set so that the gap between the photoconductor 200 and the protective film 30 is 800 to 900 μm, and charges the surface of the image carrier such as the photoconductor 200. The arrangement of the heating electrodes 70 of the charging device 90 configured by this method can be freely determined.

Here, the temperature distribution of the substrate 11 will be examined. Comparing the substrate central portion 10A and the longitudinal end 10B, both ends 10B are lower by about 5 ° C. than the central portion 10A. Therefore, in this embodiment, a heating means is arranged so as to surround the periphery of the discharge electrode 50 at the end portion 10B, which is a low-temperature portion, so that the heating value is compensated for and the temperature is secured. The temperature is made uniform. An example of the arrangement of the heating electrodes in this embodiment will be described below.

(Embodiment 1) FIG. 4 is an explanatory view showing this embodiment. Discharge means by the excitation electrode 40 and the discharge electrode 50 is formed, and the heating electrode 700 is formed.
The heating electrode 700 is formed simultaneously with the formation of the excitation electrode 40 by a thick film printing method, sputtering, or the like. The heating electrode 700 is provided in the longitudinal direction of a region where the discharge electrode and the like provided on the substrate 11 are not formed. The heating electrode 700 has a thick electrode 700A at the central portion in the longitudinal direction of the substrate, narrows the line width according to the longitudinal end direction, and forms the heating electrode 70 at the substrate end 100B.
Numeral 0 indicates a thin line electrode 700B having a reduced line width. The heating electrode 700 is connected to a power supply 800. The charging device in which the heating electrode 700 has a bold shape is simple in shape, but the wiring resistance of the heating electrode 700 is increased toward the both ends in the longitudinal direction to secure a heat generation amount.

(Embodiment 2) FIG. 5 is an explanatory view showing this embodiment. In the heating electrode 750 in this embodiment, the heat generation amount is ensured by increasing the wiring length at both ends in the longitudinal direction, which is the low temperature portion of the substrate. In the charging device shown in this embodiment, the end portion in the longitudinal direction of the substrate 11 which is the low temperature portion, the end portion 150B
, The wiring density of the heating electrode 750 provided at a high level is configured to be high. The heating electrode 750 shown in the drawing has a bent portion 755 to increase the wiring density of the heating electrode 750 at the end. In addition, the wiring pattern is not limited to the illustrated shape, and can be set arbitrarily as long as the space on the substrate 11 allows.

[0018]

As described above, the charging device according to the present invention has a configuration in which the number of parts is reduced to avoid complication of the manufacturing apparatus and increase in cost. Decompose ozone efficiently while maintaining the rate. A method for manufacturing a charging device according to the present invention provides a charging device capable of heating the entire surface of a substrate to a constant temperature with a configuration that avoids complicated manufacturing and cost increases.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the overall configuration of a charging device.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a plan view of a discharging portion of the charging device.

FIG. 4 is a schematic plan view showing the overall configuration of the charging device of the embodiment.

FIG. 5 is a schematic plan view showing the overall configuration of a charging device according to another embodiment.

FIG. 6 is a schematic diagram of a conventional charging device.

FIG. 7 is a sectional view taken along the line BB in FIG. 6;

[Explanation of symbols]

10, 100, 150 Charging device, 10B, 100
B, 150B substrate end, 11 alumina substrate,
2,20 dielectric, 3,30 protective film, 4,40
Excitation electrode, 6,50 Discharge electrode, 5,60 High voltage power supply, 70, 700, 750 Heating electrode, 80, 8
00, 850 Heating power supply, 200 Photoconductor.

Claims (5)

[Claims] 1. A plurality of linear excitation electrodes juxtaposed on the surface of a plate-like substrate formed of a dielectric, and a plurality of discharge electrodes arranged corresponding to the linear excitation electrodes via a dielectric. A charging device comprising: a heating means for heating a substrate around the excitation electrode. 2. The charging device according to claim 1, wherein the heating means for the substrate is arranged at a high density in a low temperature region of the substrate. 3. The charging device according to claim 1, wherein the heating means for the substrate comprises high-density wiring at the longitudinal end of the substrate. 4. The charging device according to claim 1, wherein the substrate heating means is formed of the same material and in the same process as the excitation electrode formed on the substrate surface. 5. A plurality of linear excitation electrodes juxtaposed on the surface of a plate-like substrate formed of a dielectric, and a plurality of discharge electrodes arranged corresponding to the linear excitation electrodes via a dielectric. A method for manufacturing a charging device comprising: a linear excitation electrode; and an electrode forming step of simultaneously forming a linear heating electrode disposed in close proximity to the excitation electrode on the same substrate. Production of a charging device including a dielectric layer forming step of forming a dielectric layer on a substrate on which a linear heating electrode is formed, and a discharge electrode forming step of forming a discharge electrode at a position corresponding to an excitation electrode on the dielectric layer Method.