JP2000173744A - Ion generating substrate, image forming device - Google Patents

Abstract

(57) Abstract: An ion is generated without unevenness, and the thickness of a protective film covering a second electrode is kept uniform to prevent deterioration. SOLUTION: A second electrode 5 opposed to a first electrode 3 with a dielectric layer 4 interposed therebetween includes a plurality of divided electrodes 5a arranged in parallel.
And a connecting portion 5b connecting the ends of these divided electrodes 5a.
And a part having a bent portion 5d that is bent substantially at a right angle, and the inner angles of the bent portions 5d are connected by a smooth curve. Accordingly, when the organometallic compound is baked on the surface of the dielectric layer 4 for forming the second electrode 5, the occurrence of distortion at the inner angle of the bent portion 5d is suppressed, the surface is kept flat, and ions are removed. It is generated evenly, and the thickness of the protective film covering the second electrode 5 is kept uniform to prevent deterioration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an ion generating substrate,
The present invention relates to a charging device, a transfer device, a charge removing device, and an image forming device.

[0002]

2. Description of the Related Art Conventionally, a first electrode, a dielectric layer, and a second electrode are sequentially laminated on the surface of an insulating substrate, and a voltage is applied between the first electrode and the second electrode. There is known an ion generating substrate in which a corona discharge is generated between the electrodes to ionize air near the electrodes.
It is also known to use the ion generating substrate as a charging device, a transfer device, and a static elimination device of an electrophotographic image forming apparatus.

In such an ion generating substrate, a plurality of divided electrodes arranged in parallel, a connecting portion connecting ends of these divided electrodes, and a conductive portion connecting the connecting portion to a power supply portion are provided. Some use first and second electrodes provided. Further, a method of forming a first electrode and a second electrode by baking an organic metal compound paste is known.

[0004]

By the way, organometallic compounds (Ag, Pt, M) are formed on the surface of the dielectric layer made of glass.
g and paste), the organometallic compound and the dielectric layer expand when heated and shrink in the process of dropping to room temperature. In this process, the dielectric layer and the organometallic compound are pulled, and the organometallic compound is distorted due to a difference in the coefficient of thermal expansion between the dielectric layer and the organometallic compound or a difference in the amount of the applied organometallic compound paste. appear. In the case of an electrode including a plurality of divided electrodes, a connection portion, and a conductive portion as described above, for example, a bent portion that is an intersection of two sides having different tensile directions, such as a portion where the divided electrode and the connection portion intersect. Wrinkles due to distortion occur in the inner corners of.

[0005] Since the wrinkles appear in the form of irregularities on the surface, the electric field concentrates on the convex portions during use, and unevenness occurs in the charged potential when the object to be charged is charged. Further, since the thickness of the protective film covering the surface of the electrode becomes thinner at the convex portion of the electrode, the protective film deteriorates at an early stage.

The second electrode is formed on the surface of the dielectric layer and has the above-mentioned problem. In the case of the first electrode, there is no problem when a dielectric layer (undercoat layer) is formed on an insulative substrate that does not require a dielectric layer, such as a glaze substrate, but a dielectric layer is formed on the insulative substrate. When the first electrode is formed, a problem similar to that of the second electrode occurs.

A power supply portion for applying a voltage to the electrode is formed on the insulating substrate, and a conductive portion of the electrode is connected to the power supply portion. The electrode formed on the surface of the dielectric layer is electrically conductive. Since the part is bent from the surface of the dielectric layer to the side and connected to the power supply part on the insulating substrate, the conductive part is disconnected at the boundary between the part that contacts the insulating substrate and the part that contacts the dielectric layer. Is easy to occur. This disconnection is due to a difference in the coefficient of thermal expansion between the insulating substrate and the dielectric layer when the organometallic compound is fired.

[0008] The present invention has been made in view of such a point, and an object of the present invention is to prevent the above-described problem from occurring when an electrode is formed by firing an organometallic compound on the surface of a dielectric layer. It is.

[0009]

According to a first aspect of the present invention, there is provided an ion generating substrate comprising: an insulating substrate; a plurality of divided electrodes arranged in parallel and a connecting portion connecting end portions of these divided electrodes. A first electrode formed on the surface of the insulating substrate; a dielectric layer formed on the surface of the insulating substrate so as to cover the first electrode; It has a plurality of arranged divided electrodes and a connecting portion connecting end portions of these divided electrodes, has a shape having a bent portion bent at a substantially right angle in part, and has an organic metal on the surface of the dielectric layer. A second electrode formed of a compound or a material containing the compound as a main component, wherein an inner angle of the bent portion is connected by a smooth curve; and a protective film covering the second electrode. Therefore, when the organometallic compound is baked on the surface of the dielectric layer for forming the second electrode, generation of distortion at the inner angle of the bent portion of the second electrode is suppressed.

The insulating substrate includes an insulating substrate having a dielectric layer on the surface and an insulating substrate having no dielectric layer. Materials for forming the first electrode and the second electrode are Ag, Pt,
An organometallic compound containing Mg, a paste, or the like, or a material containing the same as a main component is applicable. The dielectric layer covering the first electrode is formed of a dielectric mainly composed of glass.

Further, the first electrode and the second electrode include a shape in which a plurality of divided electrodes arranged in parallel are connected in a crank shape by a connection portion, and a conductive portion is connected to a part of the crank shape body. .

According to a second aspect of the present invention, there is provided the ion generating substrate according to the first aspect, wherein the insulating substrate has a dielectric layer on a surface thereof, and the first electrode is a surface of the dielectric layer of the insulating substrate. And has a shape having a bent portion bent at a substantially right angle in a part thereof, and the inner angles of the bent portions are connected by a smooth curve. Therefore, when firing the organometallic compound on the surface of the dielectric layer for the formation of the first electrode,
The generation of distortion at the inner angle of the bent portion of the first electrode is suppressed.

The dielectric layer provided on the surface of the insulating substrate is made of a dielectric mainly composed of glass.

According to a third aspect of the present invention, in the ion generating substrate according to the first or second aspect, the first electrode and the second electrode formed on the surface of the dielectric layer feed the connection portion. A conductive portion connected to the connecting portion, wherein the conductive portion and the connecting portion are connected to each other by a smooth curve at an inner angle of a continuous bent portion. Therefore, when firing the organometallic compound on the surface of the dielectric layer for the formation of the first electrode and the second electrode,
The generation of distortion at the inner angle of the bent portion where the conductive portion and the connection portion are continuous is suppressed.

According to a fourth aspect of the present invention, there is provided the image forming apparatus according to the first aspect.
The ion generating substrate according to any one of (3) to (3) is provided around the photoconductor. Therefore, it is possible to charge the object to be charged in the image forming apparatus without unevenness.

[0016]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. FIG. 1 is a plan view showing a main part of the ion generating substrate, and FIG. 2 is a vertical sectional side view of the XX line part in FIG.

The ion generating substrate 1 includes an insulating substrate 2, a first electrode 3 formed on the surface of the insulating substrate 2, a dielectric layer 4 covering the first electrode 3, and a surface of the dielectric layer 4. Electrode 5 formed on the substrate and a protective film 6 covering the second electrode 5
And a heater (not shown) formed on the lower surface of the telephoto substrate 2
Are formed.

In the present embodiment, a dielectric layer 8 is formed as an undercoat on the surface of an insulating substrate 2 made of, for example, alumina. The dielectric layer 8 is formed by screen-printing a dielectric mainly composed of glass.

The dielectric layer 4 covering the first electrode 3 is also formed by screen-printing a dielectric mainly composed of glass. At this time, screen printing is performed twice, and a thickness of 30 μm is secured. By baking after the first screen printing, air bubbles contained in the inside can be released. The protective film 6 covering the second electrode 5 is also formed by screen-printing a dielectric mainly composed of glass. The dielectric used at this time is the same as that used when the dielectric layers 4 and 8 are formed. A material having a lower softening point than the material and easy to flow is used. The first electrode 3 and the second electrode 5 are made of an organometallic compound (Ag, Pt, Mg,
(Including a paste) on the surface of the dielectric layer 8 or 4.

As shown in FIG. 1, the first electrode 3 includes a plurality of divided electrodes 3a arranged in parallel, and these divided electrodes 3a.
a connecting portion 3b for connecting the end of the connecting portion 3a and a conductive portion 3c for connecting the connecting portion 3b to a power feeding portion (not shown). It has a shape in which a bent portion 3d bent at a substantially right angle is formed at a continuous portion of the portion 3b and the conductive portion 3c.

Similarly, the second electrode 5 includes a plurality of divided electrodes 5a arranged in parallel with the divided electrodes 3a of the first electrode 3.
And a connecting portion 5b connecting the ends of these divided electrodes 5a.
And a conductive portion 5c for connecting the connection portion 5b to a power supply portion (not shown). The divided electrode 5a and the connection portion 5b
And a continuous portion between the connecting portion 5b and the conductive portion 5c.

As shown in FIG. 2, the split electrode 3a of the first electrode 3 is arranged at a position facing the gap between the adjacent split electrodes 5a of the second electrode 5.

Here, the inner angles of the bent portions 3d of the first electrode 3 are connected by a smooth curve. Specifically, the inner angle at which the divided electrode 3a and the connecting portion 3b are continuous is connected by a radius curve R1, and the inner angle at which the connecting portion 3b and the conductive portion 3c are continuous is connected by a radius curve R2. .

The inner angles of the bent portions 5d of the first electrode 5 are connected by a smooth curve. Specifically, the inner angle at which the divided electrode 5a and the connecting portion 5b are continuous is connected by a radius curve R1, and the inner angle at which the connecting portion 5b and the conductive portion 5c are continuous is connected by a radius curve R2. .

In this case, assuming that the distance between the divided electrodes 3a and 5a is a and the width of the connecting portions 3b and 5b is b, in this example, the radius of R1 is a / 2 and the radius of R2 is b / 4. But it is not limited to this value.

In this embodiment, the outer angles of the bent portions 3d of the first electrode 3 are connected by a smooth curve. Specifically, the outer angles at which the divided electrodes 3a and the connecting portions 3b are continuous are connected by a radius of R3. Further, the tip of the split electrode 3a on the side opposite to the connection portion 3b is R4
It is formed so as to draw a smooth curve with a given radius.

Similarly, the outer angles of the bent portions 5d of the second electrode 5 are connected by a smooth curve. Specifically, the outer angle at which the divided electrode 5a and the connecting portion 5b are continuous is connected by a radius curve of R3. Further, the tip of the split electrode 5a on the side opposite to the connection portion 5b is formed so as to draw a smooth curve with a radius of R4.

In this case, the radius of R3 is determined to be b / 4, and the width of divided electrodes 3a, 5a is assumed to be c, and the radius of R4 is determined to be c / 2, but is limited to this value. is not.

In such an ion generating substrate 1, the heater provided on the back surface of the insulating substrate 2 is driven to heat the insulating substrate 2, and the high frequency and high voltage are applied to the first electrode 3 and the second electrode 5. Is applied, the divided electrode 5a of the second electrode 5
A high alternating electric field is intensively generated in the gaps between the gaps, and high-density ions are generated. The mechanism of the ion generation is that the space charge generated in the air is accelerated by the electric field between the divided electrodes 5a, and the positive and negative ions are multiplied as they move while colliding with the gas molecules in the air in sequence. The movement of each of the multiplied ions is reversed, and the ions are further multiplied.

By the way, an organic metal compound is formed on the surface of the dielectric layer 8 or 4 by means of screen printing or the like, and this is fired to form the first electrode 3 and the second electrode 5. The heated dielectric layers 8 and 4 and the organometallic compound are contracted and pulled. At this time,
In a straight portion like the divided electrodes 3a and 5a, a tensile force acts in the longitudinal direction, but the bent portions 3d and 5d
Then, tensile forces act in two directions orthogonal to each other. For this reason, when the inside angles of the bent portions 3d and 5d are right angles, stress concentrates along a straight line that bisects the inside angles, but since the inside angles are connected by curves having radii of R1 and R2, distortion occurs. Is suppressed. Thus, no irregularities due to distortion are formed on the surfaces of the first electrode 3 and the second electrode 5.
Therefore, the electric field does not concentrate on a part of the first electrode 3 and the second electrode 5, whereby ions can be generated without unevenness. Further, a protective film 6 covering the second electrode 5
Since no irregularities are formed on the second electrode 5, the film thickness can be made uniform to prevent deterioration.

The outer corners of the bent portions 3d and 5d and the tips of the divided electrodes 3a and 5a are less likely to concentrate stress, but these portions are also formed in a curved shape with a radius of R3 or R4. There is no risk of distortion.

In this embodiment, since the first electrode 3 is formed on the insulating substrate 2 having the dielectric layer 8, the inner angles of the bent portions 3d of the first electrode 3 are connected by a curve having a radius of R1, R2. However, when the first electrode 3 is formed on an insulating substrate having no dielectric layer 8, the insulating substrate does not shrink like glass when the organometallic compound is fired.
No distortion occurs in the interior angle of d. Thus, it is not necessary to connect the inner angles of the bent portions 3d with a curve.

Next, a second embodiment of the present invention will be described with reference to FIGS. The same parts as those in the above embodiment are denoted by the same reference numerals, and description thereof is omitted. FIG. 3 is a plan view showing the connection relationship between the conductive portion 5c of the second electrode 5 and the power supply portion. FIG. 4 is a plan view showing the conductive portion 5 of the second electrode 5 in the YY line portion in FIG.
It is a vertical side view which shows the connection relationship between c and a feed part.

A through hole 10 surrounded by a conductive film 9 is formed in the insulating substrate 7. In this case, the conductive film 9 is formed by screen printing an alloy such as silver / palladium or silver / platinum. As shown in FIG. 2, the first electrode 3 is covered with dielectric layers 4a and 4b formed by performing screen printing twice. Since the surface of the dielectric layer 4b and the surface of the insulating substrate 7 have different height levels, the conductive portion 5c has a high level to connect the second electrode 5 formed on the surface of the dielectric layer 4b to the conductive film 9. A step portion 5e having a difference is formed.

The second electrode 5 is formed on the dielectric layer 4b by sintering the organometallic compound in the same manner as in the above embodiment, but the second electrode 5 is pulled by the shrinkage after heating. Can be At this time, the step portion 5 of the conductive portion 5c
e has a portion that contacts the dielectric layer 4b and a portion that contacts the insulating substrate 7, and the boundary between the two portions is the dielectric layer 4b.
Distortion occurs due to the difference in the coefficient of thermal expansion between b and the insulating substrate 7. Moreover, the thickness of the step portion 5e becomes thin because the material flows downward before it is solidified.

However, by setting the width of the step portion 5e to be larger than the width of the divisional electrode 5a (see FIG. 1), the strength of the step portion 5e can be reinforced and disconnection can be prevented.

The area of the second dielectric layer 4b to be formed is determined so as to cover the end of the first dielectric layer 4a, and the material of the dielectric layer 4b is glass or the like having a low softening point. When the dielectric layer 4b is used for screen printing, the dielectric layer 4b can easily flow through the dielectric layer, and the side surfaces of the dielectric layers 4a and 4b can be formed in a gentle shape. Thereby, the step portion 5e of the second electrode 5 can be connected to the conductive film 9 while maintaining a gentle shape.

When the dielectric layers 4a and 4b are screen printed in two separate steps, the size of the second dielectric layer 4b is adjusted so that the end of the first dielectric layer 4a is located outside the end. The step portion 5e can be formed in a gentle shape also by making the position smaller.

When the first electrode 3 is formed on the dielectric layer 8 of the insulating substrate 7 as shown in FIG. 2, the height of the surface of the dielectric layer 8 and the surface of the insulating substrate 7 are Since the levels are different, the conductive portion 3 is required to connect the first electrode 3 to the conductive film 9.
A step portion having a height difference is formed in c.
In this case, by making the width of the step portion wider than the width of the divided electrode 3a, disconnection during firing can be prevented.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a front view illustrating a schematic configuration of the image forming apparatus.

In the figure, reference numeral 20 denotes a photosensitive member which is driven to rotate clockwise. Around this photoreceptor 20, a charging device 21 for charging the surface of the photoreceptor 20, a static eliminator 22 for removing charges from the photoreceptor 20, and an exposure device (not shown) for writing an electrostatic latent image on the photoreceptor 20 are provided. ), The developing device 23 and the photoconductor 2
A transfer device 24 that transfers the image on the transfer paper S to the transfer paper S, a peeling device 25 that peels the transfer paper S from the photoconductor 20, and a cleaning unit 26 that cleans the surface of the photoconductor 20 are arranged. Reference numeral 27 denotes a paper feed cassette for storing a large number of transfer papers S in a stacked state, and feeds the transfer papers S in the paper feed cassette 27 one by one to a paper passage 29 extending from the paper feed cassette 27 to the fixing device 28. Paper feed roller 30 for paper
And a registration roller 31 that rotates in synchronization with an image forming process on the photoconductor 20 are arranged.

In such a configuration, the surface of the photoconductor 20 is charged by the charging device 21 in the process of being driven to rotate clockwise, and a laser beam 32 modulated based on an image signal is applied to the charged portion of the exposure device. , An electrostatic latent image is formed. This electrostatic latent image is developed by the developing device 23. On the other hand, the transfer paper S fed by the paper feed roller 30 reaches the nip of the registration roller 30 and stands by, and when the registration roller 31 is driven in synchronization with the image forming process, the transfer paper S Paper is fed between the transfer device 20 and the transfer device 24. The developed image on the photoconductor 20 is transferred to the transfer sheet S by the transfer device 24, and the transferred image is fixed by the fixing device 28 when the transfer sheet S reaches the fixing device 28. The fixed transfer sheet S is discharged to a discharge tray (not shown). The remaining toner remaining on the photoconductor 20 is wiped by the cleaning unit 26.

By the way, the charging device 21, the static elimination device 22,
The transfer device 24 includes the ion generating substrate 1 described with reference to FIGS. Of course, the peeling device 25
Alternatively, a configuration including the ion generating substrate 1 may be used. For this reason, the charging device 21, the static elimination device 22, the transfer device 24,
In the peeling device 25, ions can be generated without unevenness.

[0044]

According to the first aspect of the present invention, the second electrode facing the first electrode with the dielectric layer interposed therebetween is composed of a plurality of divided electrodes arranged in parallel and the ends of these divided electrodes. And a connecting portion to be connected, and is formed in a shape having a bent portion that is bent at a substantially right angle in part, and since the inner angles of the bent portions are connected by a smooth curve, the dielectric is formed for forming the second electrode. When baking an organometallic compound or a material containing the same as a main component on the surface of the body layer, it is possible to suppress the occurrence of distortion at the inner angle of the bent portion of the second electrode. Thereby, the surface of the second electrode can be maintained flat, and ions can be generated without unevenness. Further, the thickness of the protective film covering the second electrode can be maintained uniform to prevent deterioration.

According to the second aspect of the present invention, the first electrode formed on the dielectric layer provided on the insulating substrate and facing the second electrode connects the plurality of divided electrodes and the ends of these divided electrodes. It has a connection part, and has a shape having a bent portion that is bent at a substantially right angle in part, and the inner angles of the bent portion are connected by a smooth curve, so that the dielectric layer of the dielectric layer for forming the first electrode is formed. When baking an organometallic compound or a material containing the same as a main component on the surface, it is possible to suppress occurrence of distortion at an inner angle of a bent portion of the first electrode. Thereby, the surface of the first electrode can be maintained flat, and ions can be generated without unevenness.

According to the third aspect of the present invention, the first electrode and the second electrode formed on the surface of the dielectric layer have a conductive portion for connecting the connection portion to the power supply portion. Are connected by a smooth curve,
When firing an organometallic compound or a material containing the same as a main component on the surface of the dielectric layer for forming the first electrode and the second electrode, distortion at an inner angle of a bent portion where the conductive portion and the connection portion are continuous. Can be suppressed.

According to a fourth aspect of the present invention, there is provided the image forming apparatus according to the first aspect.
Since the ion generating substrate according to any one of the first to third aspects is provided around the photoreceptor, the object to be charged in the image forming apparatus can be charged without unevenness, so that the image quality can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view showing a main part of an ion generating substrate according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional side view of an XX line part in FIG. 1;

FIG. 3 is a plan view showing a connection relationship between a conductive portion of a second electrode and a power supply portion according to a second embodiment of the present invention.

4 is a vertical sectional side view showing a connection relationship between a conductive portion of a second electrode and a power supply portion in a YY line portion in FIG. 3;

FIG. 5 is a front view illustrating a schematic configuration of the image forming apparatus.

[Explanation of symbols]

 1: Ion generation substrate 2, 7: Insulating substrate 3: First electrode 3a: Split electrode 3b: Connection 3c: Conductive portion 3d: Bent portion 4, 4a, 4b: Dielectric layer 5: Second electrode 5a: Split electrode 5b: connection portion 5c: conductive portion 5d: bent portion 5e: stepped portion 6: protective film 20: photoconductor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shiro Ezaki 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation F-term (reference) 2H003 BB11 BB16 CC01 EE08 2H032 AA02 BA13 BA23 2H035 AA03 AA04 AB03

Claims (4)

[Claims] A first electrode formed on a surface of the insulating substrate, the insulating substrate having: a plurality of divided electrodes arranged in parallel; and a connecting portion connecting ends of the divided electrodes. A dielectric layer formed on the surface of the insulating substrate so as to cover the first electrode; a plurality of divided electrodes arranged in parallel to the divided electrodes of the first electrode; and ends of these divided electrodes. Having a shape having a bent portion bent at a substantially right angle in part, formed on the surface of the dielectric layer by an organometallic compound or a material containing it as a main component, A second electrode in which the inner angles of the bent portions are connected by a smooth curve; a protective film covering the second electrode;
An ion generating substrate comprising: 2. The insulating substrate includes a dielectric layer on a surface,
The first electrode is formed on the surface of the dielectric layer of the insulating substrate from the organometallic compound or a material containing the organometallic compound as a main component, and has a shape having a bent portion that is bent at a substantially right angle in a part thereof. 2. The ion generating substrate according to claim 1, wherein the inner angles of the portions are connected by a smooth curve. 3. The first electrode and the second electrode formed on the surface of the dielectric layer have a conductive part connecting the connection part to a power supply part, and the conductive part and the connection part are continuous. The inner angles of the bent portions are connected by a smooth curve.
Or the ion generating substrate according to 2. 4. An image forming apparatus comprising the ion generating substrate according to claim 1 around a photoreceptor.