JPH1052932A - Method of manufacturing recording head and image forming apparatus provided with the recording head - Google Patents

Abstract

(57) [Problem] To manufacture a recording head using a substrate which can be manufactured accurately and at low cost. SOLUTION: A control electrode 4 is formed on a long insulating sheet so as to be divided into a plurality of groups by dividing into joints 8. Since the pitch Ph between the control electrodes 4 at the joint 8 is set to be wider than the pitch between the control electrodes 4 in the same group, the pitch Ph between the control electrodes 4 at the joint 8 is set. To prevent the occurrence of current leakage and discharge between the control electrodes 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a recording head and an image forming apparatus provided with the recording head.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus for obtaining an image on a support by controlling the passage of toner particles through an aperture by applying an image signal to an electrode having an aperture has been proposed in US Pat. No. 3,689,935. Have been.

The image forming apparatus described in US Pat. No. 3,689,935 comprises a shield electrode continuous on one side with an insulating layer interposed therebetween and a plurality of control electrodes insulated from each other on the other side. At least one of the plurality of insulated control electrodes is formed through three layers.
An aperture electrode body having apertures arranged in a row,
A means for selectively applying a potential between the control electrode and the shield electrode, a means for supplying charged toner particles to the aperture of the aperture electrode body, and a high voltage which is disposed on a side of the support opposite to the aperture electrode body. And a means for moving the support relative to the aperture electrode body to position the support in the particle flow path.

However, according to this apparatus, the recording quality is deteriorated due to the clogging of the aperture with the toner particles, and the recording speed cannot be increased too much.

The present applicant has further studied and, as shown in JP-A-6-155798, greatly improves recording characteristics by arranging a carrier holding a toner and an aperture electrode body in contact with each other. An image recording apparatus capable of performing the above has been proposed. According to this apparatus, the aperture is not clogged, the image quality is remarkably improved, and the size and cost of the image recording apparatus can be reduced.

FIG. 7 shows a recording head of this type. The recording head 100 has a conductor 103 made of 8 μm thick copper on an insulating sheet 102 made of a 25 or 50 μm thick polyimide film or the like.
Is used, and on the appropriate substrate 101,
The driving IC 105 was mounted.

[0007]

However, when manufacturing the above-described recording head, a serious problem has occurred. In other words, this recording head requires extremely fine wiring to be used for image recording, and is considerably difficult to manufacture. For example, in the case of manufacturing a recording head having a resolution of 300 dots per inch, it is necessary to arrange at least a conductor portion of about 20 to 30 microns at a pitch of 85 microns. It has been very difficult to manufacture such wiring accurately and with good yield on a substrate having a width of 200 mm or more in the width direction.

[0008] In order to manufacture such a substrate for a recording head, it has conventionally been made on a flexible substrate (hereinafter referred to as FPC) manufacturing line. In this FPC manufacturing process, a photosensitive resist is applied to polyimide with a copper film, a circuit pattern is exposed to light, developed to form a resist mask, and then masked with an etchant such as ferric chloride. No copper was removed and the circuit pattern was completed.

In such an FPC manufacturing, the conventional wiring accuracy was about 100 μm in pitch with a minimum conductor width of 50 μm. Therefore, when a high-precision substrate such as the present recording head is manufactured, there is a problem that it is not possible to sufficiently cope with mass production in terms of accuracy and yield.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a method of manufacturing a recording head capable of sufficiently coping with mass production in terms of accuracy and yield, and an image recording apparatus having the recording head. The purpose is to provide.

[0011]

According to a first aspect of the present invention, there is provided a method for manufacturing a recording head, comprising the steps of: controlling a recording material supplied from a recording material supply means directly by an electric field; In a method for manufacturing a recording head for forming an image thereon, a large number of control electrodes divided into a plurality of groups are sequentially arranged on a substrate for each group.

This makes it possible to manufacture a recording head having a highly accurate control electrode at low cost and in a stable manner.

According to a second aspect of the present invention, the pitch between the control electrodes at one end of each of the two adjacent groups is equal to or wider than the pitch of the adjacent control electrodes in the group. It forms so that it may become.

Thus, even if the control electrodes are connected to each group, the space between the control electrodes at one end of each of the two adjacent groups becomes narrow, and current leakage and discharge do not occur. Can be performed.

The method of manufacturing a recording head according to claim 3, further comprising the step of forming an aperture between the control electrodes after the formation of a large number of control electrodes, wherein each of the plurality of control electrodes is arranged in a direction orthogonal to the arrangement direction. The electrodes are formed so that the error in the position of the control electrode for each group is equal to or less than half the size of the aperture.

Thus, the recording material is supplied to the aperture without disturbing the behavior, so that stable electric field control can be performed at any position, and uniform image recording can be realized.

According to a fourth aspect of the present invention, there is provided an image forming apparatus having a recording head for forming an image on an image receiving body by directly controlling a recording material supplied from a recording material supply means by an electric field. In, a large number of control electrodes of a recording head are divided into a plurality of groups, and each group is formed on a substrate in order.

Therefore, the present image forming apparatus can be provided with a recording head having high-precision control electrodes, and can perform high-resolution recording.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 6 is a diagram showing an outline of the image forming apparatus of the present embodiment. A columnar back electrode roller having a gap of 1 mm is provided above the aperture electrode body 1 as a recording head. 22 is rotatably provided on a chassis (not shown), and is configured to be able to transport the support 20 inserted into the gap. A toner case 11 is disposed below the aperture electrode body 1, and the toner case 11 includes a toner 16 as a recording material, a supply roller 12, and a toner carrying roller as a recording material supply unit. 14 are provided. Here, the toner carrying roller 14 carries the toner 16 and transports the toner 16 toward the aperture electrode body 1.
Reference numeral 2 denotes a unit for supplying the toner 16 to the toner carrying roller 14.

A control voltage application circuit 23 is connected between the toner carrying roller 14 and a control electrode 4 described later. The control voltage application circuit 23 is configured to apply a voltage of 0 V or +40 V to the control electrode 4 based on an image signal.

Further, a DC power supply 24 is connected between the back electrode roller 22 and the toner carrying roller 14.
A voltage of 1 kV can be applied.

Next, the recording head of this embodiment will be described.

FIG. 1 is a perspective view of a recording head for an image forming apparatus to which the present invention is applied, and FIG. 2 is an enlarged plan view particularly in the vicinity of an aperture. The aperture electrode body 1 serving as a recording head is largely composed of an insulating sheet (substrate) 2, a conducting wire 3,
C5 and aperture 6.

The insulating sheet 2 is a base material serving as a base of the aperture electrode body 1 and is required to have mechanical and electrical properties.
As the material, polyimide is usually preferable, and as a currently marketed material, upilex film (manufactured by Ube Industries), Kapton film (manufactured by Toray DuPont), and apical film (manufactured by Kanegafuchi Chemical) can be used. . The thickness of the material is desirably 50, 75, or 125 microns in view of the film rigidity, but a thickness smaller than that, for example, 25 microns can of course be used. As the material, the above-described polyimide substrate is preferable, but polyester and the like can also be used.

On the upper part of the insulating sheet 2, a conducting wire 3 is arranged. The conducting wire 3 is a so-called two-layer flexible substrate directly adhered to the insulating sheet 2 and has a copper thickness of 8 mm.
Micron. This two-layer flexible board allows finer wiring than a three-layer board in which an insulating sheet 2 and a conductive wire 3 which are usually used are bonded together with an adhesive.

At the end of the conductor pattern 3, a drive IC 5 is mounted for controlling the voltage of each hole. Drive IC5
Are mounted by a wire bonding method or a flip chip method.

Next, the aperture 6 formed on the insulating sheet 2 will be described.

As shown in FIGS. 1 and 2, the insulating sheet 2
Are formed along the longitudinal direction. Then, the control electrode 4 continuing from the conducting wire 3 is arranged so as to alternate with the aperture 6. The pitch of the control electrodes 4 is 85 microns for a resolution of 300 dpi, and the line width is 20 microns. The aperture 6 has a rectangular shape with two sides formed on the control electrode, and has a width of 80 microns.

Here, a description will be given of a main part of the present invention, in which a large number of control electrodes 4 are divided into a plurality of groups, and the groups are sequentially arranged on the insulating sheet 2 for each group.

FIG. 3 is a plan view of the circuit board in the process of forming the aperture electrode body 1. This circuit board is a so-called T
The sprocket 7 is provided on both sides of the tape because it is produced by the AB tape manufacturing process. The sprocket 7 has a rectangular hole of 1.98 mm on each side, usually 4.75 mm.
It is formed at a pitch of mm. This sprocket 7
Used to feed tapes during manufacturing. Insulation sheet 2
Is usually introduced with a slit of 40 m in length, and the control electrode 4 and the conducting wire 3 are arranged on the upper surface thereof. Between each group of the control electrode 4 and the conductive wire portion 3 arranged side by side, a joint 8 described later is shown by a two-dot chain line.

When manufacturing with a TAB tape line, first, a photosensitive resist is applied on the copper film of the insulating sheet 2. After that, by exposing each block according to the size of one frame, the photosensitive resist reacts with light to form a latent image. Then, this one block constitutes one group of the control electrode 4 and the conductive wire portion 3 to be formed later. A chemical pattern is formed on the latent image to form a resist pattern, and the resist remains in a portion where copper wiring is to be formed. Thereafter, by spraying an etching solution such as ferric chloride on the copper surface, the copper surface of the non-resist portion is removed, the copper surface of the resist portion remains, and a conductive wire pattern is formed. This is a method commonly called lithography,
This is an indispensable method for obtaining fine wiring.

At this time, it is important that the joint 8 between adjacent blocks when the exposure is performed for each block be formed well. Here, the vicinity of the joint 8 will be described with reference to FIG. FIG. 4 is an enlarged view of the control electrode 4 near the joint 8. In this figure, the joint 8 shown by a two-dot chain line is separated, and a long T
An AB tape is produced. At this time, the displacement of the control electrodes 4 adjacent to each other across the joint 8 becomes very important. In the normal position other than the joint 8, these control electrodes 4 have an adjacent pitch of 85 μm as a matter of course, and no displacement occurs in the vertical direction.
Due to a movement error of the AB tape or the like, the control electrodes 4 adjacent to each other across the joint 8 are displaced in the vertical and horizontal directions.

Therefore, in the present embodiment, the pitch between the control electrodes 4 spanning the joint 8 (Ph in the figure)
Is set to be wider than 85 microns (specifically, 87 microns). With such a wide setting, if the right and left displacement is in the range of 2 microns, the pitch between the control electrodes 4 over at least the joint 8 can be 85 microns or more. This 8
The setting of 7 microns can be freely set according to the manufacturing error of the TAB tape manufacturing line.

FIG. 5 is an enlarged plan view of the control electrode 4 near the joint 8 on which the aperture processing has been performed. The length of the aperture 6 is 80 microns as described above, but in the present embodiment, the vertical displacement (Dv in the figure) of the control electrode 4 sandwiching the joint 8 is reduced to half of 80 microns, that is, 40 microns or less. It is set to become.

Since the aperture processing is a well-known processing using an excimer laser, a detailed description of the processing is omitted (for example, Japanese Patent Application Laid-Open No. 5-124247).

As described above, according to the method of manufacturing a recording head of the present embodiment, mass production can be performed by using a TAB tape manufacturing line, which has become very popular as a conventional method of mounting a liquid crystal drive IC. Will be possible. According to this manufacturing method, a reduced exposure is performed for each divided frame in a non-contact manner, and an optical latent image is formed on a resist, so that extremely fine wiring can be manufactured with a high yield. Therefore, a substrate on which good wiring patterns are arranged can be manufactured at low cost.

Further, the aperture electrode body 1 of the present embodiment
Is used in a direct recording apparatus using the toner 16. At this time, since the setting of the pitch (Ph) between the control electrodes 4 of the joint 8 is 85 μm or more, the distance between them is There is no case where the distance between the normal control electrodes 4 becomes narrower.

When recording is performed, plus 40 V is applied to the control electrode 4 corresponding to the dot to be printed, and 0 V is applied to the dot not to be printed, in accordance with the print data by the drive IC 5. In addition, if the pitch between the control electrodes 4 at the joint 8 is smaller than the pitch between the control electrodes 4 at the normal position, a current leaks between the control electrodes 4 or a discharge occurs in an emergency, thereby damaging the head. Was. That is, changing the pitch of the control electrodes creates a very dangerous situation for applying a voltage between the adjacent electrodes.

However, if the adjacent pitch between the control electrodes 4 at the joint 8 is larger than the adjacent pitch between the control electrodes 4 at the normal position as in the present embodiment, the control electrodes 4 adjacent at the joint 8 are different. Even if voltage is applied, the distance is longer than usual, so current leakage and discharge do not occur,
Voltage can be stably applied.

Further, the vertical displacement (D
As described with respect to v), the aperture 6 is formed between the control electrodes 4 as described above, and the portion of the control electrode 4 extending from the tip of the aperture 6 in the direction opposite to the direction of the drive IC 5 is: It has been found that it greatly affects the print quality. If this length is approximately half or more of the length of the aperture 6, when a voltage is applied during printing, the moving state of the transported toner 16 is affected by the electric field, and a cause of fogging occurs. Would.

Therefore, in the normal section, the amount of protrusion of the control electrode 4 is set to an extremely small value, for example, about several microns as compared with the size of the aperture 6. Regarding the joint 8, the amount of vertical displacement (Dv) is restricted to at least half the length of the aperture 6 from the restriction of the amount of protrusion. Thereby, when the apertures 6 are formed in a line, the amount of the control electrodes 4 protruding from the apertures 6 also increases with respect to the group of the control electrodes 4 adjacent at the joint 8.
Since the amount is within the specified amount, good printing can be performed.

The present invention is not limited to the embodiment described in detail above, and various changes can be made without departing from the gist of the present invention. The gist of the present invention is to use a tape-shaped substrate created for each block, divide a large number of control electrodes into a plurality of groups, and sequentially form each group on the substrate, so that an accurate and inexpensive recording head can be obtained. To manufacture.

For example, in this embodiment, an example in which the present invention is applied to a recording head of a direct recording type printing apparatus has been described. However, the present invention can be applied to a liquid crystal panel or a driving circuit applied to an ink jet head.

[0045]

As is apparent from the above description, according to the method of manufacturing a recording head according to claim 1 of the present invention,
Since a large number of control electrodes divided into a plurality of groups are sequentially formed on the substrate for each group, a recording head having high-precision control electrodes can be stably manufactured at low cost. Will be possible.

According to the method of manufacturing a recording head of the present invention, the pitch between the control electrodes at one end of each of two adjacent groups is the same as the pitch of adjacent control electrodes in the group. Alternatively, since the recording head is formed so as to be wider, a recording head capable of performing reliable recording without adversely affecting image recording can be manufactured even if the control electrodes are connected for each group.

Furthermore, according to the recording head manufacturing method of the present invention, the error in the position of the control electrode for each group in the direction orthogonal to the direction in which the plurality of groups are arranged is less than half the size of the aperture. Since the supplied recording material is supplied without disturbing the behavior, stable electric field control can be performed at any position, and a recording head capable of realizing uniform image recording can be manufactured.

According to the image forming apparatus of the present invention, a large number of control electrodes of the recording head are divided into a plurality of groups, and the control electrodes of each group are sequentially formed on the substrate. High-resolution recording can be performed by a recording head having highly accurate control electrodes.

[Brief description of the drawings]

FIG. 1 is a perspective view of an aperture electrode body according to an embodiment of the present invention.

FIG. 2 is a detailed plan view near the aperture of the aperture electrode body.

FIG. 3 is a plan view of wiring on a circuit board in a process of forming the aperture electrode body.

FIG. 4 is a plan view showing a vicinity of a joint of the circuit board.

FIG. 5 is a plan view showing the vicinity of a joint of the circuit board on which an aperture is formed.

FIG. 6 is a configuration diagram of an image forming apparatus provided with the aperture electrode body.

FIG. 7 is a perspective view of a conventional recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aperture electrode body 2 Insulating sheet 3 Conductor wire 4 Control electrode 6 Aperture 8 Joint

Claims (4)

[Claims] 1. A method of manufacturing a recording head for forming an image on an image receiving body by directly controlling a recording material supplied from a recording material supply means by an electric field, comprising the steps of: forming a plurality of control electrodes divided into a plurality of groups; Forming a recording head on a substrate in a group. 2. The method according to claim 1, wherein the pitch between the control electrodes at one end of each of the two adjacent groups is equal to or wider than the pitch of the adjacent control electrodes in the group. Item 2. The method for manufacturing a recording head according to Item 1. 3. The method according to claim 1, further comprising the step of forming an aperture between the control electrodes after the formation of the large number of control electrodes, and an error in the position of the control electrodes for each group in a direction orthogonal to the arrangement direction of the plurality of groups. 2. The method according to claim 1, wherein the aperture is formed so as to be equal to or less than half the size of the aperture. 4. An image forming apparatus comprising a recording head for forming an image on an image receiving body by directly controlling a recording material supplied from a recording material supply means by an electric field, wherein a plurality of control electrodes of the recording head are provided. Is an image forming apparatus provided with a recording head, wherein the image forming apparatus is divided into a plurality of groups and is formed on a substrate in order for each group.