JPH11317280A - Ion generating substrate and electrophotographic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve smoothness of the surfaces of electrodes. SOLUTION: Even when a substrate 1 having inferior surface smoothness, for example a ceramics substrate 1, is used, an undercoat layer 51 having the surface smoothness and electrical insulation higher than those of the surface of the substrate 1 and the main component of which is, for example, a glass material is formed on the surface of the substrate 1. First electrodes 2, and second electrodes 4, etc., which generate corona discharges between the first electrodes 2 and themselves to generate ions in the atmosphere are formed on the undercoat layer 51. Thereby, the first electrodes 2, etc., are not influenced by the surface roughness of the substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion generating substrate used for, for example, a charging device in electrophotography, and an electrophotographic recording apparatus using the same.

[0002]

2. Description of the Related Art In recent years, as an ion generating device used for a charging device of an electrophotographic recording device such as a copying machine or a laser printer, an ion generating device in which an electrode for inducing a corona discharge is formed in a film shape on a ceramic substrate. Substrates are being developed.

As this type of ion generating substrate, for example, one disclosed in Japanese Patent Application Laid-Open No. 8-82980 is known. In this ion generating substrate, two electrodes are formed on a ceramic substrate with a dielectric layer interposed therebetween by a film forming technique. Then, an AC voltage is applied between these electrodes to generate corona discharge between the two electrodes to ionize the air near the electrodes. Hereinafter, the ion generating substrate will be described in detail.

FIG. 9 is a conceptual diagram showing a conventional ion generating substrate and electric wiring when the substrate is used for a charging device. In FIG. 9, a first electrode 102 is formed on a substrate 101 by a film forming technique. The first electrode 102 and the substrate 101 are covered with a dielectric layer 103. A second electrode 104 is formed on the dielectric layer 103 by a film forming technique. The second electrode 104 is arranged so as not to be located directly above the first electrode 102. The dielectric layer 103 and the second electrode 104 are covered with a protective layer 108.

[0005] The ion generating substrate formed in this manner is, as shown in FIG. 9, in a state where it is incorporated in an electrophotographic recording apparatus as a charging device for a photoconductor, and is provided with a photoconductor 105.
Are arranged facing each other at a predetermined interval. Then, a high-frequency voltage is applied between the first electrode 102 and the second electrode 104 by the high-frequency power supply 106, and the polarity periodically changes between the first and second electrodes as indicated by the arrow in FIG. Then, positive and negative ions are generated in the air near the two electrodes, that is, on the surface of the ion generating substrate.
At this time, the DC power source 107 applies a zero potential between the second electrode 104 and the photoconductor 105 so that the photoconductor 105 is at a zero potential.
When a bias voltage having a negative side is applied, negative ions of the generated positive and negative ions are attracted to the photoconductor 105 and the photoconductor 105 is uniformly charged.

In this case, the charging potential of the photosensitive member 105 can be set by adjusting a bias voltage applied between the second electrode 104 and the photosensitive member 105.

Here, FIG. 10 is a sectional view showing the ion generating substrate conceptually shown in FIG. 9 closer to the actual form. As shown in FIG. 10, the first electrode 102 and the second electrode 1
04 is actually formed by alternately arranging a plurality.

[0008]

However, the above-mentioned ion generating substrate has the following problems.

FIG. 11 is an enlarged sectional view showing a portion including one first electrode 102 and two second electrodes 104. Ceramics such as alumina used as a material of the substrate 101 have poor surface smoothness. Therefore, as shown in FIG. 11, the surface of the substrate 101 has a large surface roughness. On the other hand, since the first electrode 102 is often a thick film formed by a pressure film technique such as screen printing in consideration of the manufacturing labor and manufacturing cost, as shown in FIG.
There is a problem that the surface roughness of the first electrode 102 is directly reflected on the first electrode 102, and the surface of the first electrode 102 also has a large surface roughness.

As described above, when the surface roughness of the first electrode 102 increases, air enters the interface between the first electrode 102 and the dielectric layer 103 formed thereon, and the dielectric layer 103
There is a disadvantage that air bubbles are generated in the liquid crystal and its withstand voltage is deteriorated. In addition, since the thicknesses of the dielectric layer 103 and the protective layer 108 are not uniform, the first electrode 102
Because the electric field tends to concentrate on the convex portions of the irregularities on the surface of the substrate, the amount of generated ions is non-uniform, and the dielectric layer 103 and the protective layer 108 are greatly deteriorated in the strong electric field portion, resulting in a shorter life. There are inconveniences.

Another problem is that the conventional first electrode 1
12, the dielectric layer 103 immediately above the first electrode 102 rises as shown in FIG. 12, and the dielectric layer 103 is formed on each of the first electrodes 102 as shown in FIG. There is also a problem that it is difficult to make the thickness of the layer 103 uniform. This is more remarkable as the thickness of the first electrode 102 is larger.

In the portion where the thickness of the dielectric layer 103 is large, there is a disadvantage that the impedance to the leakage electric field penetrating through the dielectric layer 103 is increased and the ionic current is reduced. Therefore, for example, when the ion generating substrate is used as a charging device for the photoconductor, there is a problem that a sufficient amount of ions cannot be obtained and the photoconductor 105 cannot be charged to a desired potential.

An object of the present invention is to provide an ion generating substrate and an electrophotographic recording apparatus having excellent withstand voltage.

Another object of the present invention is to provide a long life ion generator and electrophotographic recording apparatus.

Another object of the present invention is to provide an ion generating substrate and an electrophotographic recording apparatus having excellent ion generating characteristics.

[0016]

According to a first aspect of the present invention, there is provided an ion generating substrate, comprising: a substrate; an undercoat layer formed on the substrate and having an electrical insulating property and a surface smoothness higher than the surface of the substrate; A first electrode formed on the undercoat layer,
A second electrode formed on the undercoat layer at a distance from the first electrode and causing a corona discharge between the first electrode and the first electrode to generate ions in the atmosphere; and a protection covering the first electrode and the second electrode. And a layer.

Structures in the present claims and the following claims are defined as follows unless otherwise specified.

The "substrate" is suitably a ceramic substrate such as alumina, aluminum nitride or silicon nitride for reasons of ease of formation and low cost, but is not limited thereto. In addition, the forming method is not limited.

The "undercoat layer" is formed mainly of, for example, a glass material. For example, it is formed by applying lead borosilicate glass by a screen printing method and firing it. By forming the undercoat layer with such a material, surface smoothness higher than the surface of the substrate is easily imparted to the undercoat layer. Further, since the periphery of the first electrode is completely covered with the electric insulating layer, it is easy to secure electric insulation between the first electrode and the outside.

The "first electrode" and the "second electrode" can be formed, for example, by applying and firing a conductive paste containing silver as a main component (silver / palladium alloy, silver / platinum alloy, etc.) by a screen printing method. However, the material and the forming method are not particularly limited. The first electrode and the second electrode may be formed using different materials and different forming methods. The first electrode and the second electrode may be formed of a conductor of an organometallic compound, as in the invention described in claim 7 described later. In this case, it can be formed by applying a conductive paste containing an organometallic compound as a main component by a screen printing method and firing it.

The "protective layer" can be, for example, a glass layer formed by a screen printing method using a lead borosilicate glass paste, a film of silica or the like, or a film of resin (polyimide, epoxy, silicone) or the like. However, the material and the forming method are not limited to these.

Further, in order to favorably generate ions in the protective layer, it is preferable that the thickness of the portion covering the electrode is about 10 μm or less, but this is not necessary.

Further, "a second electrode which is formed separately from the first electrode and generates a corona discharge between the first electrode and ions in the atmosphere" means, for example, the first electrode and the second electrode. 2
By arranging the electrodes side by side on the same surface, or forming one electrode on top of the other with the one electrode shifted left and right so that it does not completely cover the upper part of the other electrode, etc. This means that each electrode is formed so that a leakage electric field generated between the first electrode and the second electrode can be present in the atmosphere.

According to the first aspect of the present invention, when a high-frequency voltage is applied between the first electrode and the second electrode, both electrodes are caused by corona discharge between the first electrode and the second electrode. Positive and negative ions are generated in the space in the vicinity. When the ion generating substrate according to the first aspect of the present invention is used as, for example, a charging device for charging a photoconductor, the ion generating substrate is opposed to the photoconductor, and the first electrode or the second electrode is connected to the photoconductor. During that time, for example, a bias voltage is applied so that the photoconductor has zero potential and the electrode side is negative. As a result, the photoconductor is uniformly charged at a negative potential.

At this time, the first electrode or the first and second electrodes formed on the undercoat layer have a smooth surface due to the surface smoothness of the undercoat layer. Therefore, the first electrode or the first electrode and the second electrode
It is possible to prevent air from entering the interface between the electrode and the protective layer, and to maintain good withstand voltage at that portion. In addition, since the first electrode or the first electrode and the second electrode have excellent surface smoothness, an electric field is not locally concentrated, whereby the ion generation amount is made uniform and the ion generation characteristics are improved. And the life is prolonged.

According to a second aspect of the present invention, there is provided an ion generating substrate formed on a substrate, an undercoat layer formed on the substrate and having an electrical insulating property and a surface smoothness higher than the surface of the substrate, and an undercoat layer. A first electrode, a dielectric layer formed over the undercoat layer and the first electrode, and a corona discharge formed between the first electrode and the first electrode to cause ions to enter the atmosphere. And a protective layer covering the dielectric layer and the second electrode.

The “dielectric layer” according to the present invention can be, for example, a glass layer formed by using a lead borosilicate glass paste by screen printing or a glass layer containing an alumina ceramic filler. However, the present invention is not limited to this, and the forming method is not limited. When the first electrode and the second electrode are formed via the dielectric layer as in the present invention, the second electrode is formed so as to be spaced apart from the first electrode via the dielectric layer in the vertical direction. Therefore, in the left-right direction, electrical insulation between the first and second electrodes can be performed without providing a large space between the first and second electrodes, and thereby the width of the ion generating substrate can be reduced. .

According to the ion generating substrate of the present invention, for example, the photosensitive member can be charged similarly to the ion generating substrate according to the first aspect. At this time, the first electrode formed on the undercoat layer has a smooth surface due to the surface smoothness of the undercoat layer. For this reason, it is possible to prevent air from entering the interface between the first electrode and the dielectric layer, and to maintain good withstand voltage at that portion. In addition, since the surface of the first electrode has excellent smoothness, the electric field does not concentrate locally, whereby the ion generation amount is uniformed, the ion generation characteristics are improved, and the life is extended. Become.

According to a third aspect of the present invention, in the ion generating substrate according to the first or second aspect, the undercoat layer is formed mainly of a glass material.

The undercoat layer according to the present invention can be implemented in various forms, for example, a glass layer formed by using a lead borosilicate glass paste by a screen printing method or a glass layer containing an alumina ceramic filler. it can. In any case, since the undercoat layer is formed using a glass material as a main component, the undercoat layer can easily have higher surface smoothness than the surface of the substrate.

Here, in the ion generating substrate according to any one of claims 1 to 3, the undercoat layer may have a multilayer structure. That is, an undercoat layer having a multilayer structure can be formed by forming an undercoat layer on the lower layer side on the surface of the substrate and forming an undercoat layer on the upper layer side thereon. In this case, the number of undercoat layers is not limited to two, but may be three or more. Thus, the undercoat layer has a multilayer structure, and the characteristics of the undercoat layer can be variously changed by using different characteristics for each undercoat layer.
For example, if the softening point of the undercoat layer on the upper layer side is higher than the softening point of the undercoat layer on the lower layer side, it is possible to reduce the influence of heat on the undercoat layer due to repeated firing after the formation of the undercoat layer. . If the softening point of the uppermost undercoat layer is lower than the softening point of the lower undercoat layer, the surface of the undercoat layer can be formed more smoothly.

According to a fourth aspect of the present invention, there is provided an ion generating substrate, comprising: a substrate; a first electrode formed on the substrate by a conductor of an organometallic compound; a dielectric layer formed over the substrate and the first electrode; A second electrode is formed on the body layer and generates a corona discharge between the first electrode and the first electrode to generate ions in the atmosphere. The protective layer covers the dielectric layer and the second electrode.

In the present invention, as the "conductor of an organometallic compound", gold, silver, platinum or the like can be used, of which gold is preferred. However, the conductor of the organometallic compound is not limited to these.

The first electrode formed by the conductor of the organometallic compound has a small thickness, and the dielectric layer immediately above the first electrode rises,
The problem that it is difficult to make the thickness of the dielectric layer uniform for each first electrode is solved. This avoids the disadvantage that the impedance with respect to the leakage electric field penetrating the dielectric layer and the protective layer increases and the ion current decreases, and the ion generation characteristics are improved.

According to a fifth aspect of the present invention, in the ion generator of the fourth aspect, the second electrode is formed of a conductor of an organometallic compound.

In the present invention, gold, silver, platinum and the like can be used as the "conductor of an organometallic compound", and among these, gold is preferable. However, the conductor of the organometallic compound is not limited to these.

As described above, the second electrode formed of the organometallic compound conductor has a small thickness, whereby the protective layer immediately above the second electrode rises, and each second electrode has The problem that it is difficult to make the thickness of the protective layer uniform is solved. This avoids the disadvantage that the impedance with respect to the leakage electric field penetrating the protective layer increases and the ion current decreases, and the ion generation characteristics are improved.

According to a sixth aspect of the present invention, there is provided an electrophotographic recording apparatus comprising: a photoreceptor; a charging device formed mainly of the ion generating substrate according to any one of the first to fifth aspects to charge the photoreceptor; An image exposure device that exposes the exposed photoconductor to form an electrostatic latent image, a developing device that attaches toner to the electrostatic latent image formed on the photoconductor to develop the image, and a developing device that forms the developed image formed on the photoconductor. The image forming apparatus includes a transfer device for transferring to a transfer medium, and a fixing device for fixing a transferred image on the transfer medium.

According to the electrophotographic recording apparatus of the present invention, image recording is performed through basic processes of electrophotography such as charging, exposing, developing, and transferring a photosensitive member. And
An ion generating substrate is provided so as to face the photoconductor, and ions are generated by applying a high-frequency voltage between the first electrode and the second electrode. By applying a bias voltage between the second electrode and the photoreceptor, for example, the photoreceptor is at zero potential and the second electrode is negative, the negative ions of the positive and negative ions generated near the two electrodes are exposed to light. The photoreceptor is charged by being sucked by the body. In this case, the charging device has the function of the ion generating substrate according to any one of the first to fifth aspects.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an ion generating substrate according to the present invention will be described with reference to FIGS. FIG.
FIG. 2 is a front view showing a first embodiment of the ion generating substrate of the present invention. FIG. 2 is a rear view. FIG. 3 is a sectional view taken along line AA in FIG. FIG. 4 is a cross-sectional view showing a part of the enlarged view.

In FIG. 1, reference numeral 1 denotes a substrate. An undercoat layer 51 is formed on the substrate 1, and a first electrode 2, a dielectric layer 3, a second electrode 4, and a protective layer 5 are sequentially formed on the undercoat layer 51. . The dielectric layer 3 covers almost the entire surface of the first electrode 2 and the substrate 1. At this time, the second electrode 4 is formed without covering the upper part of the first electrode 2, and an electrode gap is formed between the first electrode 2 and the second electrode 4. The protective layer 5 covers the second electrode 4 with a thickness necessary to protect the second electrode 4. The first electrode 2 is formed integrally with the first terminal 2a, and the first electrode 2 is formed in a comb blade shape having six blades and the second electrode is formed in a comb blade shape having seven blades. The second electrode 4 is formed integrally with the second terminal 4a, and power is supplied to each electrode by the first terminal 2a and the second terminal 4a. Further, a heater 7 for heating the present ion generating substrate itself is formed on the surface opposite to the surface on which the first electrode 2 and the like are formed on the substrate 1. This heater 7
Has an effect of removing moisture adhering to the surface of the ion generating substrate on which the first electrode 2 and the second electrode 4 are formed by the heat generated. Thereby, the first electrode 2 and the second electrode 2
The leakage electric field between the electrode 4 and the electrode 4 prevents the current from flowing through the above-mentioned moisture, thereby preventing the leakage electric field in the air from affecting the amount of generated ions.

The substrate 1 is a flat rectangular member made of alumina ceramic and has a length of about 360 m.
m, a width of about 8 mm and a thickness of about 0.65 mm.

The undercoat layer 51 has a thickness of about 20 μm, for example, formed by applying a glass paste containing lead borosilicate glass as a main component on the substrate 1 by a screen printing method and then firing. . Such an undercoat layer 51 has electrical insulation properties and surface smoothness higher than the surface of the substrate 1. However, the undercoat layer 51 is not limited to such a material, and may be any material having electrical insulation and a surface smoothness higher than the surface of the substrate 1 irrespective of its type. May be.

The first electrode 2 and the second electrode 4 are formed, for example, by applying a conductive paste containing an organic metal compound as a main component by a screen printing method and then firing the paste. The width of the first electrode 2 is about 100 μm, and the width of the second electrode 4 is about 200 μm. Further, the center distance between the first electrode 2 and the second electrode 4 in the width direction is about 600 μm.

The dielectric layer 3 is formed by applying and baking a glass paste containing, for example, a lead borosilicate glass as a main component in the same manner as the first electrode 2, and has a thickness of about 30 μm.
Is formed. Here, the dielectric layer 3 has a two-layer structure. The lower layer side is a lead borosilicate glass containing an alumina filler up to about 30%, and the upper layer side is a borosilicate containing no or low filler. Lead glass is used as a main component. Thereby, the lower dielectric layer 3
Has a characteristic that the dielectric layer 3 on the upper layer side is excellent in surface smoothness because it contains no filler or contains a small amount of the filler.

The protective layer 5 is formed by printing using a glass paste mainly composed of lead borosilicate glass and has a thickness of 10 μm.
m or less.

The heater 7 is formed by applying a conductive paste containing, for example, a silver-palladium alloy as a main component by a screen printing method and then firing the applied paste. The heater 7 has a U-shape, and heater terminals 7 a and 7 b for power supply are integrally formed at both ends, that is, at one end of the substrate 1. The length of the heater 7 in the U-shape is about 320 mm, and the heater 7 is formed so as to face the entire region of the first electrode 2 and the second electrode 4 in the longitudinal direction. The region where ions are generated can be satisfactorily heated.

In such a configuration, when a high-frequency voltage of, for example, 2.5 KV pp at 5 KHz is applied between the first electrode 2 and the second electrode 4, the voltage between the first electrode 2 and the second electrode 4 is increased. By corona discharge, an ion current of about 5 μA could be generated in the air near the electrode gap, specifically at a position separated by 0.7 mm from the surface of the ion generating substrate. The ambient temperature at this time was about 70 ° C.
When the ion generating substrate of the present embodiment is used, for example, as a charging device for charging a photoreceptor (not shown), the ion generating substrate is disposed so as to face the photoreceptor, and a photoreceptor is provided between the second electrode 4 and the photoreceptor. A bias voltage is applied so that the body is at zero potential and the second electrode side is negative. Then, the negative ions of the generated positive and negative ions are attracted to the photoconductor, and the photoconductor is uniformly charged.

Here, as shown in FIG. 4, since the substrate 1 is made of alumina ceramics, its surface is rough. On the other hand, the undercoat layer 51
Is formed on the undercoat layer 51 even if the surface roughness of the substrate 1 is rough because the surface smoothness is excellent.
The surface smoothness of the undercoat layer 51 is also reflected on the electrode 2, and the surface of the first electrode 2 is formed smooth. Therefore, when forming the dielectric layer 3, the first electrode 2 and the dielectric layer 3
This prevents air from entering the interface with the air bubbles and generating bubbles in the portion, and the withstand voltage of the portion is maintained satisfactorily. In addition, since the surface of the first electrode 2 is excellent in smoothness, the electric field is not locally concentrated, whereby the ion generation amount is uniformed, the ion generation characteristics are improved, and the life is improved. become longer.

The first electrode 2 is formed of a conductor of an organometallic compound. Therefore, the thickness of the dielectric layer 3 formed as an upper layer of the first electrode 2 does not rise so that a portion directly above the first electrode 2 does not rise, and the thickness of the dielectric layer 3 is reduced. Sex is maintained. Therefore, when the thickness of the dielectric layer 3 is too large, the stray capacitance between the first electrode 2 and the second electrode 4 increases by that much, and the impedance with respect to the leakage electric field penetrating the dielectric layer 3 is reduced. Inconveniences such as an increase in the ion current and a decrease in the ion current are avoided, and the ion generation characteristics are improved.

Further, in the dielectric layer 3 of the ion generating substrate of the present embodiment, as described above, the surface of the upper dielectric layer 3 has excellent smoothness, and Since the two electrodes 4 also have excellent surface smoothness, the occurrence of pinholes and variations in thickness of the protective layer 5 immediately above the second electrodes 4 can be reduced. Therefore, even when the sputtering effect due to ion collision reaches the protective layer 5, the second electrode 4 is hardly exposed, and the durability of the second electrode 4 is improved. in this case,
Since the second electrode 4 formed of a conductor of an organometallic compound has a small thickness, the surface smoothness of the second electrode 4 itself is also good. As described above, since the lower dielectric layer 3 has excellent withstand voltage, there is no fear of dielectric breakdown or the like.

A second embodiment of the ion generating substrate according to the present invention will be described with reference to FIG. FIG. 5 is a vertical sectional side view of the ion generating substrate. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, the undercoat layer 51
Has a two-layer structure. That is, the lower undercoat layer 51a is formed on the substrate 1, and the upper undercoat layer 51b is formed thereon. In this case, the softening point of the upper undercoat layer 51b is formed higher than the softening point of the lower undercoat layer 51a.

In such a configuration, the ion generating substrate of the present embodiment also has the same operation and effect as the ion generating substrate of the first embodiment. In the ion generating substrate of the present embodiment, since the softening point of upper undercoat layer 51b is higher than the softening point of lower undercoat layer 51a, it is repeated when forming each layer formed after formation of undercoat layer 51. The influence of heat on the undercoat layer 51 due to the firing is reduced.

A third embodiment of the ion generating substrate of the present invention will be described with reference to FIG. FIG. 6 is a vertical side view of the ion generating substrate. The same parts as those in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the present embodiment, the undercoat layer 51
Has a three-layer structure. That is, similarly to the second embodiment, the lower undercoat layer 51a is formed on the substrate 1, and the upper undercoat layer 51b is formed thereon. In the present embodiment, the upper undercoat layer 51a is formed.
The uppermost undercoat layer 51c is further formed on the layer b. In this case, the softening point of the uppermost undercoat layer 51c is lower than the softening point of the upper undercoat layer 51b.

In such a configuration, the ion generating substrate of the present embodiment also has the same operation and effect as the ion generating substrates of the first and second embodiments. In the ion generating substrate of the present embodiment, the softening point of uppermost undercoat layer 51c is lower than the softening point of upper undercoat layer 51b, so that the surface of undercoat layer 51 is formed more smoothly.

A fourth embodiment of the ion generating substrate according to the present invention will be described with reference to FIG. FIG. 7 is a longitudinal sectional view of the ion generating substrate. Note that the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the ion generating substrate of the present embodiment, the first
The electrode 2 and the second electrode 4 are both formed directly on the undercoat layer 51 without being positioned in a vertical relationship via the dielectric layer 3. That is, the first electrode 2 and the second electrode 4 are formed so as to be adjacent to every other on the undercoat layer 51. Therefore, in the ion generating substrate of the present embodiment, the dielectric layer 3 is not provided, and the protective layer 5 is formed directly on the first electrode 2 and the second electrode 4. The first electrode 2 of the present embodiment
The second electrode 4 is also made of a conductor of an organometallic compound, as in the first embodiment.

In such a configuration, one electrode 2 and the second electrode
When a high-frequency voltage is applied between the first electrode 2 and the second electrode 4, an ion current can be generated in air near the electrode gap by corona discharge between the first electrode 2 and the second electrode 4. When the ion generating substrate of the present embodiment is used, for example, as a charging device for charging a photoreceptor (not shown), the ion generating substrate is disposed so as to face the photoreceptor, and a photoreceptor is provided between the second electrode 4 and the photoreceptor. A bias voltage is applied so that the body is at zero potential and the second electrode side is negative. Then, the negative ions of the generated positive and negative ions are attracted to the photoconductor, and the photoconductor is uniformly charged.

Here, as shown in FIG. 7, since the substrate 1 is made of alumina ceramics, the surface roughness is rough. On the other hand, the undercoat layer 51
Is formed on the undercoat layer 51 even if the surface roughness of the substrate 1 is rough because the surface smoothness is excellent.
The surface smoothness of the undercoat layer 51 is also reflected on the electrode 2 and the second electrode 4, and the surfaces of the first electrode 2 and the second electrode 4 are formed smooth. Therefore, when the protective layer 5 is formed, air does not enter into the interface between the first electrode 2 and the second electrode 4 and the protective layer 4 and bubbles are not generated in that portion, and the withstand voltage of the portion is prevented. The properties are favorably maintained. In addition, since the surfaces of the first electrode 2 and the second electrode 4 have excellent smoothness, the electric field does not concentrate locally, whereby the ion generation amount is uniformed and the ion generation characteristics are good. And the service life will be longer.

The first electrode 2 and the second electrode 4 are formed of a conductor of an organometallic compound. For this reason,
As a result, the thickness of the protective layer 5 formed as an upper layer of the first electrode 2 and the second electrode 4 becomes small, and the portion directly above the first electrode 2 and the second electrode 4 rises. And its smoothness is maintained.
Therefore, if the thickness of the protective layer 5 becomes too large, the stray capacitance between the first electrode 2 and the second electrode 4 increases by that much, and the impedance to the leakage electric field penetrating through the dielectric layer 3 increases. Inconveniences such as a reduction in ion current are avoided, and the ion generation characteristics are improved.

In the ion generating substrate of the present embodiment, as described above, since it is formed on the undercoat layer 51 having excellent smoothness and formed of the conductor of the organometallic compound, Because the thickness is thin,
The surface smoothness of the first electrode 2 and the second electrode 4 is excellent. For this reason, the occurrence of pinholes and variations in thickness of the protective layer 5 immediately above the first electrode 2 and the second electrode 4 can be reduced. Therefore, even when the sputtering effect due to ion collision reaches the protective layer 5, the first electrode 2 and the second electrode 4 are hardly exposed, and their durability is improved.

An embodiment of the electrophotographic recording apparatus according to the present invention will be described with reference to FIG. FIG. 8 is a schematic side view showing the inside of the embodiment of the electrophotographic recording apparatus of the present invention. The same parts as those described with reference to FIGS. 1 to 11 are denoted by the same reference numerals, and description thereof will be omitted.

First, a paper feed path 13 is provided for connecting a paper feed device 12 for storing transfer paper 11 as a transfer medium and a paper discharge unit (not shown). The paper feed path 13 includes a fixing device 14. An image processing unit 15 is provided.

The image processing section 15 is mainly composed of a photosensitive drum 16 having a photosensitive drum configuration. Around the photoconductor 16, a charging device 17, a developing device 18, a transfer device 1
9, a peeling device 20, and a cleaning device 21 are arranged in this order. An exposure position EX is defined between the charging device 17 and the developing device 18, and the image processing unit 15 supplies a laser beam (hereinafter, referred to as a laser beam) to the exposure position EX.
An image exposure device (not shown) for irradiating the light is provided. Here, as the charging device 17, the charging device 17 including a desired one of the ion generating substrates of the above-described embodiments is used.

Next, the operation of the image processing section 15 will be described. In the image processing unit 15, first, the charging device 1
7, the photosensitive member 16 is uniformly charged with negative charge. Since the photoconductor 16 is uniformly charged at the exposure position EX, by irradiating the exposure position EX with a light beam from an image exposure apparatus according to image information,
An electrostatic latent image is formed on the photoconductor 16. Here, photoconductor 1
In No. 6, since the electrical resistance is reduced only in the portion irradiated with the light beam, the charged electric charge is erased and an electrostatic latent image is formed. The developing device 18 visualizes the electrostatic latent image formed on the photoreceptor 16 by attaching toner having a potential difference to the electrostatic latent image on the photosensitive member 16 at the exposure position EX. The transfer device 19 sucks the developed image on the photoconductor 16 by a potential difference,
Peeling device 20 for transferring the developed image to transfer paper 11
Removes the transfer paper 11 after the transfer of the developed image from the photoconductor 16. The cleaning device 21 performs cleaning by, for example, scraping off toner remaining on the photoconductor 16 after the transfer process. The fixing device 14 is disposed downstream of the transfer device 19 in the paper passage path 13 and fixes unfixed toner adhering to the transfer paper 11 after passing through the transfer device 19 by a heating / pressing action. I do.

In such an electrophotographic recording apparatus,
Since the charging device 17 including a desired one of the ion generating substrates of the above-described embodiments is used as the charging device 17, the charging device 17 also has the same effect as the ion generating substrate used. Become.

In this embodiment, the example in which the ion generating substrate shown in each of the above embodiments is used for the charging device 17 has been described. However, in the embodiment, the ion generating substrate may be used for the transfer device 19. Although it is not provided in the electrophotographic recording apparatus of the embodiment, it may be applied to a photoreceptor 16 removing device.

[0070]

According to the first aspect of the present invention, the first electrode or the first electrode is provided on the undercoat layer having excellent surface smoothness.
Since the electrode and the second electrode are formed, the surface of the first electrode or the first electrode and the second electrode can be formed smoothly by the surface smoothness of the undercoat layer, whereby the first electrode or the first electrode can be formed. In addition, it is possible to prevent air bubbles from entering the interface between the second electrode and the protective layer due to the intrusion of air, and it is possible to maintain good withstand voltage at that portion. In addition, since the smoothness of the surface of the first electrode or the first electrode and the second electrode is excellent, local concentration of an electric field on the first electrode or the first electrode and the second electrode can be prevented. The ion generation amount can be made uniform by improving the ion generation amount, and
The life of the ion generating substrate can be extended.

According to the second aspect of the present invention, since the first electrode is formed on the undercoat layer having excellent surface smoothness, the surface of the first electrode is formed smoothly by the surface smoothness of the undercoat layer. Accordingly, it is possible to prevent the generation of air bubbles due to the intrusion of air into the interface between the first electrode and the dielectric layer, and it is possible to maintain good withstand voltage at that portion. In addition, since the surface of the first electrode is excellent in smoothness, local concentration of an electric field on the first electrode can be prevented, whereby the ion generation amount can be made uniform and the ion generation characteristics can be improved. In addition, the life of the ion generating substrate can be extended.

According to the third aspect of the present invention, since the undercoat layer is formed mainly of a glass material,
Surface smoothness and electrical insulation higher than the surface of the substrate can be easily imparted to the undercoat layer, and the production thereof can be facilitated.

According to the fourth aspect of the present invention, since the first electrode is formed of a conductor of an organometallic compound, the first electrode can be formed thin, and thus, the dielectric layer formed as an upper layer of the first electrode can be formed. In the layer or the protective layer, it is possible to prevent the portion directly above the first electrode from rising, and to improve the ion generation characteristics.

According to the fifth aspect of the present invention, since the second electrode is formed of a conductor of an organometallic compound, the second electrode can be formed thinly, whereby the protective layer formed as an upper layer of the second electrode can be formed. In this case, it is possible to prevent the portion directly above the second electrode from rising, and to improve the ion generation characteristics.

According to the sixth aspect of the present invention, the charging device is excellent in withstand voltage, has a long life, and has a high ion generating characteristic due to the function and effect of the ion generating substrate according to any one of the first to fifth aspects. An electrophotographic apparatus including a charging device having excellent characteristics can be provided.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of an ion generating substrate of the present invention.

FIG. 2 is a rear view thereof.

FIG. 3 is a sectional view taken along line AA in FIG.

FIG. 4 is a longitudinal sectional view showing a part of the enlarged view.

FIG. 5 is a longitudinal sectional view showing a second embodiment of the ion generating substrate of the present invention.

FIG. 6 is a longitudinal sectional view showing a third embodiment of the ion generating substrate of the present invention.

FIG. 7 is a longitudinal sectional view showing a fourth embodiment of the ion generating substrate of the present invention.

FIG. 8 is a schematic side view showing an embodiment of the electrophotographic recording apparatus of the present invention.

FIG. 9 is a conceptual diagram showing an example of a conventional ion generating substrate and electric wiring when the substrate is used for a charging device.

FIG. 10 is a longitudinal sectional view showing an example of a conventional ion generating substrate.

FIG. 11 is an enlarged longitudinal sectional view showing a part thereof.

FIG. 12 is a vertical cross-sectional view showing a part of the image further enlarged.

[Explanation of symbols]

 1: Substrate 2: First electrode 3: Dielectric layer 4: Second electrode 5: Protective layer 14: Fixing device 16: Photoconductor 17: Charging device 18: Developing device 19: Transfer device 51: Undercoat layer

Claims (6)

[Claims] An undercoat layer formed on the substrate and having electrical insulation and a surface smoothness higher than the surface of the substrate; a first electrode formed on the undercoat layer; A second electrode formed on the coat layer and spaced from the first electrode and causing a corona discharge between the first electrode and the first electrode to generate ions in the atmosphere; a protective layer covering the first electrode and the second electrode And an ion generating substrate comprising: 2. a substrate; an undercoat layer formed on the substrate and having electrical insulation and a surface smoothness higher than the surface of the substrate; a first electrode formed on the undercoat layer; A dielectric layer formed over the coat layer and the first electrode; and a second electrode formed on the dielectric layer and causing a corona discharge between the first electrode and the first electrode to generate ions in the atmosphere; A protective layer that covers the dielectric layer and the second electrode. 3. The ion generator according to claim 1, wherein the undercoat layer is formed mainly of a glass material. A first electrode formed on the substrate by a conductor of an organometallic compound; a dielectric layer formed over the substrate and the first electrode; a dielectric layer formed on the dielectric layer;
An ion generating substrate, comprising: a second electrode that generates corona discharge by generating corona discharge between the first electrode and the first electrode; and a protective layer that covers the dielectric layer and the second electrode. 5. The ion generating substrate according to claim 4, wherein the second electrode is formed of a conductor of an organometallic compound. 6. A photoreceptor; a charging device formed mainly of the ion generating substrate according to claim 1 for charging the photoreceptor; and exposing the photoreceptor charged by the charging device to static electricity. An image exposure device for forming an electrostatic latent image; a developing device for applying toner to an electrostatic latent image formed on the photoconductor to develop the image; and a transfer device for transferring a developed image formed on the photoconductor to a transfer medium A fixing device for fixing a transferred image on a transfer medium;