JPH08118721A - Manufacture of ion flow electrostatic recording head - Google Patents

Abstract

PURPOSE: To manufacture a low-cost ion flow electrostatic recording head in which highly minute image of the same degree as a mica can be formed without deteriorating a dielectric layer even at a temperature for a long period. CONSTITUTION: This method for manufacturing an ion flow electrostatic recording head comprises the steps of forming a thin film 13 made of at least an organic metallic compound as the forming material of a dielectric layer 3 at a first electrode 2 side on an insulating board 1, and then forming the layer 3 having a thickness of 1 to 5μm on the electrode 2 by the film 14 of the metallic oxide formed by burning the film 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an ion flow electrostatic recording head used for electrostatic printing and copying.

[0002]

2. Description of the Related Art Generally, for example, in electrostatic printing,
There is known an electrostatic recording apparatus in which ions having a high current density are generated, which are extracted and selectively applied to a member to be charged to charge the member to be charged on an image.

In an ion flow electrostatic recording head used in this electrostatic recording apparatus, as shown in FIGS. 2A and 2B, it extends substantially linearly in the same direction on an insulating substrate 1 and has a substantially linear shape. A plurality of first electrodes 2 arranged in parallel are provided. These first electrodes 2 are fixed to one surface of the dielectric layer 3.

A plurality of second electrodes 4 extending in a direction different from the extending direction of the first electrode 2 are fixed to the other surface of the dielectric layer 3. The plurality of first electrodes 2 ... And the plurality of second electrodes 4 ... Form a matrix.
Further, an opening 4a for ion generation is formed in a portion of the second electrode 4 corresponding to the matrix.

Further, a third electrode 6 is provided on the opposite side of the second electrode 4 from the first electrode 2 with an insulator layer 5 interposed therebetween. Openings 5a and 6a corresponding to the openings 4a of the second electrode 4 are formed in the insulator layer 5 and the third electrode 6, and the ion flow passage opening 7 is formed by these openings 5a and 6a. Has been done.

Then, by alternately applying a high voltage between the first electrode 2 and the second electrode 4 corresponding to the selected portion of the matrix between the first electrode 2 and the second electrode 4, Positive and negative ions are generated in the vicinity of the opening 4a of the second electrode 4 facing the portion.

A bias voltage is applied between the second electrode 4 and the third electrode 6, and only ions determined by the polarity thereof are selectively extracted from the generated ions and passed through the ion flow passage port 7. The member to be charged, which is arranged so as to face the third electrode 6, can be partially charged. Therefore, electrostatic recording by dots can be performed by selectively driving the electrodes having the matrix structure.

By the way, it is required that the dielectric material forming the dielectric layer 3 used in the ion flow electrostatic recording head does not cause dielectric breakdown even with a high voltage applied for ion generation. Further, since the dielectric layer 3 needs to have a thickness sufficient to efficiently generate ions and withstand dielectric breakdown, a layer having a high dielectric constant is suitable.

Conventionally, mica has been used as the dielectric material of the dielectric layer 3, and this mica has been fixed to the electrode via the adhesive 8 made of an organic polysiloxane adhesive, but the yield of mica is poor. However, since it is expensive, the dielectric layer 3 is recently formed by dispersing fine particles of titanium oxide in an organic polymer material such as a silicone-modified polyester-alkyd resin as disclosed in JP-A-2-153760. The method to do is proposed.

Here, when the dielectric layer 3 is formed, a fine powder of titanium oxide is dispersed in an organic polymer material such as a silicone-modified polyester-alkyd resin to form a paste, which is directly applied onto the electrode. , A method of curing is shown. In this case, the paste is dried and cured at 100 ° C. for 1 hour and 150 ° C. for 5 hours at a high temperature for a long time.

[0011]

By the way, at the time of driving the ion flow electrostatic recording head, by discharging under a high voltage between the first electrode 2 and the second electrode 4, members around this,
Particularly, the dielectric layer 3 existing between the electrodes 2 and 4 is exposed to high temperature. When an organic polymer resin is used as the binder of the dielectric layer 3, the binder of the dielectric layer 3 undergoes thermal oxidative deterioration in a relatively short time, the polymer chains are cut into pieces, and the dielectric layer 3 You can see the phenomenon that powder gradually blows from the surface.

Therefore, each opening 4 of the second electrode 4 is aged with time.
Due to the change in the electrical characteristics in a, the existence of parts where ions cannot be generated uniformly, and the occurrence of electrical leakage and short circuit, the image quality of the electrostatically recorded image is also degraded, and a high-definition image can be obtained. There is no problem.

Further, the conventionally used mica as a dielectric material is superior to other dielectric materials in electrical characteristics and durability, but since it is a natural material, it has a uniform thickness and uniform electrical characteristics. It is very difficult to select and select a material that satisfies characteristics such as pinholes and other defects, and homogeneity. Therefore, the cost becomes high, and the dielectric layer 3 made of mica is produced.
There is a problem that the ion flow electrostatic recording head using is expensive.

The present invention has been made in view of the above circumstances, and an object thereof is that the dielectric layer does not deteriorate even at a temperature for a long time, a high-definition image similar to that of mica can be formed, and it is inexpensive. Another object of the present invention is to provide a method of manufacturing an ion flow electrostatic recording head that can be manufactured.

[0015]

According to a first aspect of the present invention, a thin film made of at least an organometallic compound as a material for forming a dielectric layer is formed on the first electrode side of an insulating substrate of an ion flow electrostatic recording head. After that, a dielectric layer forming step of forming a dielectric layer having a thickness of 1 μm or more and 5 μm or less on the first electrode is provided by using a metal oxide thin film formed by heating and baking this. It is a method of manufacturing an ion flow electrostatic recording head.

According to a second aspect of the present invention, there is provided the method of manufacturing an ion flow electrostatic recording head according to the first aspect, wherein at least the thin film made of the organometallic compound is an energy ray hardening type forming material.

According to a third aspect of the present invention, a wettability of the gold surface is formed by forming a polar surface of ozone on the gold surface formed on at least one of the first electrode and the second electrode of the ion flow electrostatic recording head. A method of manufacturing an ion flow electrostatic recording head, comprising: a wettability improving step for improving the wettability; and a film forming step for forming a metal oxide film on the gold surface having the improved wettability by ozone. Is.

[0018]

According to the first aspect of the present invention, a thin film of at least an organometallic compound is applied on the first electrode on the insulating substrate to form a film, which is then dried and baked to cause an oxidative decomposition reaction of the organometallic compound. To produce a metal oxide to form a ceramic dielectric layer.

According to the second aspect of the present invention, when a thin film made of an organometallic compound, which is an energy ray-curable forming material, is applied on the first electrode on the insulating substrate to form a film, the thin film is dried with a solvent and then a predetermined film is formed. By curing a thin film of an organometallic compound in an energy ray irradiation furnace, removing the uncured portion, and then baking it, the organometallic compound undergoes an oxidative decomposition reaction to produce a metal oxide, and a ceramic dielectric layer is formed. It is designed to be formed.

According to the third aspect of the present invention, a polar surface is formed by ozone on the gold surface formed on at least one of the first electrode and the second electrode of the ion flow electrostatic recording head to improve the wettability of the gold surface. By improving this, by forming a metal oxide film on the gold surface whose wettability is improved by ozone, it is possible to form a ceramic dielectric layer on the gold surface where it is difficult to generate oxides. Is.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a method of manufacturing an ion flow electrostatic recording head according to the present invention will be described below with reference to FIGS.
Will be described with reference to. In this embodiment, FIG. 2 (A), (B)
The insulating substrate 1 of the ion flow electrostatic recording head shown in FIG.
As shown in (A), it is formed of a 0.6 mm thick glazed alumina substrate (hereinafter referred to as an alumina substrate) 11.

On the plate surface of the alumina substrate 11, a resinate type gold paste is printed in a solid state by screen printing. After drying and baking, an electrode pattern 12 of the first electrode 2 having a thickness of 1 μm is formed by photoetching. To be done.

Next, a dielectric layer forming step of forming the dielectric layer 3 on the first electrode 2 side on the alumina substrate 11 is performed. In this dielectric layer forming step, the surface of the first electrode 2 on the alumina substrate 11 is preliminarily set to 254 in air.
Irradiation with ultraviolet rays of nm or less for 30 minutes. After that, a solution containing titanium as a metal among the solution “MPS” (trade name) manufactured by Epoxy Technology Co., which contains an organometallic complex as an organometallic compound and to which a solvent or a polymer is added, is used as an alumina substrate. 11 is applied to the first electrode 2 side by screen printing. As a result, as shown in FIG. 1B, a thin film 13 made of at least an organometallic compound as a material for forming the dielectric layer 3 is formed on the first electrode 2 side of the alumina substrate 11.

After the thin film 13 is formed, the heating temperature is 1
The solvent is exerted and removed at 00 ° C for 30 minutes. Then, the thin film 13 is exposed and baked at a heating temperature of 350 to 400 ° C. for 30 minutes in an infrared furnace in which the upper limit of the heating temperature is set to 400 ° C. At this time, the thin film 13 made of an organometallic compound causes an oxidative decomposition reaction to generate a metal oxide, and a thin film 14 of titanium oxide shown in FIG. 1C is formed. Layer 3 is formed. At this time, the formed titanium oxide thin film 14 has a thickness of 4 μm.

Next, 0.1 μ of chromium 15 is sputtered on the titanium oxide thin film 14 (dielectric layer 3).
m, and then 0.3 μm of gold 16 is deposited. Further, a metal layer 17 in which the chromium 15 and the gold 16 are laminated is formed in FIG.
As shown in (D), the electrode pattern 20 of the second electrode 4 is formed by photoetching the predetermined pattern of the second electrode 4 and further forming the rhodium plating 19 on the remaining conductor portion 18 to a thickness of 0.1 μm. It is formed.

After the second electrode 4 is formed, a film-shaped insulator layer 21 is vacuum laminated on the alumina substrate 11 and the second electrode 4. The insulating film of the insulating layer 21 is subjected to photoetching treatment such as exposure and development in the same manner as a normal photosensitive film so as to correspond to each opening 4a of the second electrode 4 as shown in FIG. 1 (E). Opening 21a in the part to be
Is formed.

Next, as shown in FIG. 1 (F), the second electrode 4
Insulator in a state where the third electrode 23 in which the openings 22a corresponding to the openings 4a of ... Are preliminarily formed and the openings 21a of the insulator layer 21 and the openings 23a of the third electrode 23 are aligned with each other. Overlaid on layer 21, an ion flow electrostatic recording head is manufactured. The third electrode 23 is made of, for example, stainless foil by photo-etching, and the insulator layer 2 is formed.
The first electrode and the third electrode 23 may be attached to the insulator layer 21 from above the third electrode 23 with a single-sided tape, instead of being attached with an adhesive or a double-sided tape.

Therefore, the ion flow electrostatic recording head manufactured by the above method has the following effects. That is, during the manufacturing process of the ion flow electrostatic recording head, after forming a thin film 13 made of at least an organometallic compound as a material for forming a dielectric layer on the first electrode 2 side on the alumina substrate 11, this is heated and baked. Since the dielectric layer forming step of forming the dielectric layer 3 having a thickness of 4 μm on the first electrode 2 is performed by the thin film 14 of the metal oxide formed as described above, the ceramic dielectric having a high density and a high cohesive force is formed. The body layer 3 can be formed. Therefore, the heat resistance of the dielectric layer 3 is high, the coefficient of thermal expansion is low, the dielectric layer 3 is not easily deteriorated by thermal oxidation due to discharge, and the initial electrical characteristics can be maintained for a long time.

After the thin film 13 is formed, the titanium oxide thin film 14 is formed at a heating temperature of 350 to 400 ° C. for 3 hours.
Since it is exposed and baked for 0 minutes, the surface of the formed dielectric layer 3 is leveled due to the low temperature rise at a high temperature. Therefore, the surface of the ceramic dielectric layer 3 is smooth and has good adhesiveness, so that the adhesion of the second electrode 4 can be improved. As a result, the discharge across the dielectric layer 3 is stabilized over time,
Since the amount of generated ions is uniform, it is possible to form a high-definition image as high as mica and to manufacture a durable ion flow electrostatic recording head at low cost.

In the dielectric layer forming step, since the gold surface of the first electrode 2 on the alumina substrate 11 is previously irradiated with ultraviolet rays of 254 nm or less for 30 minutes in the atmosphere, It is possible to decompose and remove organic contaminants on the gold surface of the first electrode 2 and activate oxygen in the atmosphere to ozone to physically adsorb it to the gold surface of the first electrode 2 to temporarily A polar surface can be formed to improve the wettability of the gold surface. Therefore, like gold, it is generally difficult to adsorb oxygen,
Since it is difficult to form a stable oxide, it is difficult for the surface to be hydrophilic, and as a result, the wettability is poor, and liquid compounds with various additives added to the organometallic compound, especially those with low viscosity, are repelled. The first electrode 2 whose wettability is improved by ozone even when using a material that is difficult to apply uniformly
By forming the metal oxide film on the gold surface, it is possible to surely form the uniform dielectric layer 3 made of ceramic on the gold surface of the first electrode 2 in which the oxide is hard to generate.

Next, a second embodiment of the present invention will be described. This example is a solution "MPS" manufactured by Epoxy Technology Co., Ltd. which is a material for forming a metal oxide thin film containing an organometallic complex as an organometallic compound as in the first example.
Instead of forming the dielectric layer 3 using (trade name), the dielectric layer 3 is formed using an ultraviolet curable organometallic compound having an acryloyl group and a metal atom in the molecule and a photopolymerization initiator added. It was formed. The other parts are the same as those in the first embodiment.

The UV-curable organometallic compound used in this example is an organotitanium compound having the structure shown in the following chemical formula 1 and has photocurability. Benzophenone was added as a photopolymerization initiator to this, and a solvent was used.

[0033]

Embedded image

This was first treated with a surface-treated gold surface.
Spindle coating on electrode 2 1500rpm
Apply with. Subsequently, the solvent in the applied ultraviolet-curable organometallic compound is volatilized and removed, and then the substrate is sufficiently exposed to ultraviolet rays through a photomask on which a negative pattern of the dielectric layer 3 is drawn. Next, after developing and removing the uncured portion in the ultraviolet-curable organometallic compound with a predetermined solvent, it is inserted into a high-temperature furnace in the air and baked at a heating temperature of 360 ° C. for 30 minutes to obtain a ceramic dielectric. The body layer 3 is formed.

Therefore, the ion flow electrostatic recording head manufactured by the above method has the following effects. That is, in this embodiment, as in the first embodiment, it is possible to form the ceramic dielectric layer 3 that is dense and has high cohesive force.
The heat resistance of the dielectric layer 3 is high, the coefficient of thermal expansion is low, the dielectric layer 3 is less susceptible to thermal oxidation deterioration due to discharge, and the initial electrical characteristics can be maintained for a long time.

Furthermore, since the surface of the ceramic dielectric layer 3 is smooth and has good adhesiveness, the adhesion of the second electrode 4 can be improved. As a result, the dielectric layer 3
The discharge sandwiched by is stabilized over time, the amount of generated ions becomes uniform, and a highly precise and durable ion flow electrostatic recording head can be manufactured at low cost.

Further, since the dielectric layer 3 is formed by using an ultraviolet curable organometallic compound having an acryloyl group and a metal atom in the molecule and a photopolymerization initiator added, there is no need for a particularly large scale facility. However, the dielectric layer 3 can be easily formed in a complicated pattern.

Next, a third embodiment of the present invention will be described. This example is a solution "MPS" manufactured by Epoxy Technology Co., Ltd. which is a material for forming a metal oxide thin film containing an organometallic complex as an organometallic compound as in the first example.
Instead of forming the dielectric layer 3 using (trade name), 20 wt% of a photocurable resin "TB-3041N" (trade name) manufactured by ThreeBond Co., Ltd. is added to "MPS" used in the first embodiment. A dielectric layer is formed by using the added ultraviolet curable organometallic compound. The other parts are the same as those in the first embodiment. The treatment conditions for the UV-curable organometallic compound used in this example are the same as those in the first example.

Therefore, the ion flow electrostatic recording head manufactured by the above method has the following effects. That is, in this embodiment, as in the first embodiment, it is possible to form the ceramic dielectric layer 3 that is dense and has high cohesive force.
The heat resistance of the dielectric layer 3 is high, the coefficient of thermal expansion is low, the dielectric layer 3 is less susceptible to thermal oxidation deterioration due to discharge, and the initial electrical characteristics can be maintained for a long time.

Further, since the surface of the ceramic dielectric layer 3 is smooth and has good adhesiveness, the adhesion of the second electrode 4 can be improved. As a result, the dielectric layer 3
The discharge sandwiched by is stabilized over time, the amount of generated ions becomes uniform, and a highly precise and durable ion flow electrostatic recording head can be manufactured at low cost.

Further, since the mixture of the organometallic compound and the photocurable polymer is used as the molding material of the dielectric layer 3, the dielectric layer 3 can be easily formed in a complicated pattern, and the second layer can be formed easily. Since a commercially available blend can be used without synthesizing a special compound as in the example, the dielectric layer 3 can be manufactured at low cost.

The present invention is not limited to the above embodiment. For example, an organometallic compound used as a substance for forming the dielectric layer 3 of the ion flow electrostatic recording head used in the present invention is oxidized and decomposed by being burned at a high temperature in the atmosphere like an organometallic complex to be decomposed into a metal. It changes into an oxide. As the metal used as the organometallic compound, any metal can be used as long as it can be an organometallic compound and the produced metal oxide exhibits an insulating property. For example, as the material often used for forming the dielectric layer 3, aluminum, titanium, zirconium, magnesium, tantalum,
There is silicon etc.

The organic metal compound is used in a liquid state by adding various solvents, fillers, high molecular monomers, oligomers, polymers, etc., if necessary. If the organometallic compound has an acryloyl group, a methacryloyl group, etc. in the molecule, or the polymer monomer or oligomer to be added is a photocurable type such as containing an acryloyl group, a methacryloyl group, etc. A polymerization initiator, a sensitizer, a stabilizer and the like are also added.

In order to use this, a heat-resistant printed circuit board must be used as the insulating substrate 1. Normally, a plate-shaped product obtained by firing ceramic powder such as alumina or aluminum nitride, or a glass plate is used. To use. Although there is a substrate made of a heat-resistant organic polymer material such as polyimide, it is not kept at the firing temperature of the organometallic compound.

In the dielectric layer forming step, a screen is used as a means for coating the surface of the first electrode 2 on the alumina substrate 11 with an organometallic compound to which an additive is appropriately added in a clean room to have a uniform film thickness. Other than printing, spray,
Techniques such as dipping and spin coating can also be applied.

Further, after the thin film 13 of the organometallic compound is formed, when the solvent is exerted / removed, it is kept at 80 to 150 ° C. for 3 minutes.
It may be dried for 0 minutes or more, and after drying, this thin film 13
In the firing process of, the temperature is raised in steps at 2 to 5 ° C./minute,
3 at high temperature in the atmosphere above 0 ℃ or in oxygen atmosphere
You may bake for 0 minutes or more.

When an energy ray-curable organometallic compound is used, the solvent may be dried, the coating may be cured in a predetermined energy ray irradiation furnace, and the uncured portion may be removed before firing. Here, the thickness of the formed dielectric layer 3 is in the submicron range to about 5 μm,
If it is smaller than μm, the withstand voltage against the applied voltage of the ion flow electrostatic recording head may be insufficient and dielectric breakdown may occur. If it exceeds 5 μm, the residual stress of the film increases and the film cracks. The thickness of the dielectric layer 3 is preferably 1 μm or more and 5 μm or less.

The outermost layer material of the first electrode 2 may be any metal that is not easily oxidized during firing of the dielectric layer 3,
Gold, platinum, palladium, rhodium and the like are preferable, but aluminum, nickel and the like are also applicable.

Further, in the first embodiment, the gold surface of the first electrode 2 on the alumina substrate 11 was previously exposed to 2
By irradiating with ultraviolet rays of 54 nm or less for 30 minutes, organic substances on the gold surface of the first electrode 2 are decomposed and decomposed.
A method for activating oxygen in the air atmosphere to ozone and physically adsorbing this to the gold surface of the first electrode 2 to temporarily form a polar surface to improve the wettability of the gold surface is shown. However, it can be replaced by exposing the gold surface to an ozone atmosphere sufficiently.

Further, it goes without saying that various modifications can be made without departing from the scope of the present invention. Next, other characteristic technical matters of the present application will be additionally described as follows.

(Additional Item 1) A plurality of first electrodes that extend in a substantially straight line in the same direction on the insulating substrate and are arranged substantially in parallel, and a direction different from the extending direction of these first electrodes. A plurality of second electrodes that are extended to form a matrix together with the first electrodes and that have openings formed in portions corresponding to the matrix;
Between the first electrode and the second electrode, a third electrode is provided on the opposite side of the first electrode corresponding to the second electrode, and an opening is formed in a portion corresponding to the matrix. An ion having an arranged dielectric layer and an electrode formed between the second electrode and the third electrode, wherein an opening is formed in a portion of the insulator insulator corresponding to the matrix. In the method for manufacturing a flow electrostatic recording head, a thin film of at least an organometallic compound is formed on a first electrode, and a thin film of a metal oxide is formed on the first electrode by heating and baking the thin film to a thickness of 1 μm or more and 5 μm or more. A method of manufacturing an ion flow electrostatic recording head, comprising the following step of forming a dielectric layer.

(Additional Item 2) A method for manufacturing a second ion flow electrostatic recording head according to claim 2, wherein the thin film made of at least an organometallic compound is an energy ray curable type.

(Additional Item 3) A plurality of first electrodes, which extend in a substantially straight line in the same direction on the insulating substrate and are arranged in parallel in a substantially linear manner, and a direction different from the extending direction of these first electrodes. A plurality of second electrodes that are extended and form a matrix together with the first electrodes and that have openings formed in portions corresponding to the matrix; and a plurality of second electrodes that are opposite to the first electrodes corresponding to the second electrodes. A third electrode having an opening formed at a portion corresponding to the matrix, a dielectric layer disposed between the first electrode and the second electrode, the second electrode and the third electrode. Three
An insulator disposed between the electrode and an electrode, wherein an opening is formed in a portion of the insulator corresponding to the matrix, at least a first electrode, One of the surfaces of the second electrode is made of gold, and the step of exposing the surface to UV irradiation or an ozone atmosphere and the step of forming a metal oxide film on the surface are carried out. Method for manufacturing an electrographic recording head.

[0054]

EFFECTS OF THE INVENTION According to the present invention, the dielectric layer does not deteriorate even at a temperature for a long time, a high-definition image can be formed at the same level as mica, and it can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a manufacturing process of an ion flow electrostatic recording head according to a first embodiment of the invention.

FIG. 2A is a longitudinal sectional view of a main part showing a schematic configuration of an ion flow electrostatic recording head, and FIG. 2B is a sectional perspective view of the ion flow electrostatic recording head.

[Explanation of symbols]

1 ... Insulating substrate, 2 ... First electrode, 3 ... Dielectric layer, 4 ... Second
Electrodes, 11 ... Alumina substrate, 13 ... Organometallic compound thin film, 14 ... Metal oxide thin film.

Claims (3)

[Claims] 1. A thin film made of at least an organometallic compound as a material for forming a dielectric layer is formed on the first electrode side on an insulating substrate of an ion flow electrostatic recording head,
An ion flow comprising a dielectric layer forming step of forming a dielectric layer having a thickness of 1 μm or more and 5 μm or less on the first electrode by using a metal oxide thin film formed by heating and baking the metal oxide. Method of manufacturing electrostatic recording head. 2. The method of manufacturing an ion flow electrostatic recording head according to claim 1, wherein at least the thin film made of the organometallic compound is an energy ray-curable forming material. 3. A wettability for improving the wettability of the gold surface by forming a polar surface of ozone on the gold surface formed on at least one of the first electrode and the second electrode of the ion flow electrostatic recording head. An ion flow electrostatic recording head manufacturing method comprising: an improvement step; and a film formation step of forming a metal oxide film on the gold surface whose wettability is improved by ozone.