JPH05104776A - Production of ion flow electrostatic recording head - Google Patents

Abstract

PURPOSE:To enhance the image quality of an electrostatic latent image by uniformizing a discharge state by uniformly applying an adhesive to the entire surface of a dielectric layer. CONSTITUTION:Dielectric paste prepared by dispersing a filler composed of a fine powder of inorg. matter in an org. polymeric material containing a solvent is applied to an insulating substrate 7 and dried and cured to form a dielectric layer 6. Next, the surface 60 of the dielectric layer 6 is irradiated with ultraviolet rays to be modified so as to enhance the wettability of an adhesive S and a second electrode 5 is fixed to the surface 6a of the dielectric layer 6 through the adhesive S.

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 in an electrostatic recording apparatus for performing electrostatic printing or copying.

[0002]

2. Description of the Related Art Generally, in electrostatic printing or the like, for example, a high current density ion is generated and selectively extracted and applied to a member to be charged, and the member to be charged is imagewise charged. Electronic recording devices are known.

An ion flow electrostatic recording head used in this electrostatic recording apparatus has a dielectric layer and a plurality of first electrodes fixed to one side of the dielectric layer and extending in a first direction, and the dielectric layer. A plurality of second electrodes fixed to the other side of the first electrode and extending in a direction intersecting the extension direction of the first electrode, and the plurality of first electrodes and the plurality of second electrodes form a matrix.

By alternately applying a high voltage between the first electrode and the second electrode corresponding to the selected portion of this matrix, positive and negative ions are generated in the vicinity of the second electrode facing the portion. Occurs. The generated ions can be selectively extracted to charge the member to be charged. Therefore, electrostatic recording by dots can be performed by selectively driving the electrodes having a matrix structure.

By the way, it is required that the dielectric material forming the dielectric layer used here does not cause dielectric breakdown even at a high voltage applied for ion generation. Further, the dielectric layer needs to have a high dielectric constant because it needs a thickness that efficiently generates ions and can withstand dielectric breakdown.

Further, the conditions of the adhesive for adhering the dielectric layer and the second electrode are heat resistance capable of withstanding heat generated by application of a high voltage, and the adhesive between the dielectric layer and the second electrode. Flexibility to withstand the stress generated by the difference in coefficient of thermal expansion, high adhesive strength to withstand the tensile shearing force that acts during the assembly process of the ion flow electrostatic recording head, and corona discharge resistance that is strong against discharge due to ion generation are required. To be done.

Therefore, for example, Japanese Patent Laid-Open No. 2-153760.
In the publication, as a dielectric substance forming this dielectric layer, 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. Then, the dielectric layer is formed by applying this dielectric paste on a flexible substrate and curing it by heating. Further, a silicone pressure sensitive adhesive is used as the adhesive.

[0008]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
When a silicone-based pressure-sensitive adhesive is used as an adhesive for adhering the dielectric layer and the second electrode as in Japanese Patent Publication No. 760, the adhesion between the surface of the dielectric layer and the surface of the second electrode is only due to the adhesive force. Need to be fixed.

However, since the pressure-sensitive adhesive has a characteristic that it is strong against peeling force but weak against shearing force, the conventional pressure-sensitive adhesive described above has a characteristic that after the assembly process of the ion flow electrostatic recording head. Tensile shear force that acts in the process, 1
Heat during thermal processing at around 00 ° C or heat generated by ion generation during use of the ion flow electrostatic recording head (80
The pressure-sensitive adhesive cannot withstand the stress caused by (.degree. C.), a positional shift occurs between the dielectric layer and the second electrode, and the image quality of the electrostatic latent image deteriorates.

Therefore, in recent years, a structure has been adopted in which the dielectric layer and the second electrode are bonded by an anaerobic acrylic adhesive which is more resistant to shearing force than a pressure sensitive adhesive.

In this case, since the adhesive between the dielectric layer and the second electrode has a remarkably low dielectric constant as compared with the dielectric layer, the generation of ions, which is the dielectric characteristic of the entire ion flow electrostatic recording head, is prevented. In order to ensure a certain level of ease, it is necessary to keep the thickness of the low dielectric constant adhesive layer disposed on the dielectric layer to 5 μm or less.

However, since the surface of the dielectric layer is a silicone-modified resin surface, when the anaerobic acrylic adhesive is diluted with a solvent and applied to the surface of the dielectric layer with a thickness of about several microns, the dielectric The adhesive repels water on the surface of the layer,
There is a problem that a uniform thin adhesive layer cannot be formed. As a result, the state of discharge from the ion flow electrostatic recording head is likely to be non-uniform, and the amount of generated ions varies, which causes the problem that the image quality of the electrostatic latent image varies.

The present invention has been made in view of the above circumstances, and an object thereof is to be able to uniformly apply an adhesive to the entire surface of the dielectric layer, to make the discharge state uniform and to form an electrostatic latent image. An object of the present invention is to provide a method of manufacturing an ion flow electrostatic recording head that can improve image quality.

[0014]

According to the present invention, a plurality of first electrodes are provided on an insulating substrate in a substantially straight line extending in the same direction and arranged in parallel in a substantially parallel manner, and the extending direction of these first electrodes. A plurality of second electrodes extending in a different direction from each other, forming a matrix with the first electrode, and having an opening formed in a portion corresponding to the matrix; and the first electrode with respect to the second electrode. A third electrode disposed on the opposite side of the electrode and having an opening formed in a portion corresponding to the matrix; a dielectric layer disposed between the first electrode and the second electrode; A method of manufacturing an ion flow electrostatic recording head, comprising: an insulator disposed between two electrodes and a third electrode, wherein an opening is formed in a portion of the insulator corresponding to the matrix. First electrode formation for forming the first electrode on an insulating substrate Then, on the insulating substrate on which the first electrode is formed, a dielectric paste in which a filler composed of an inorganic fine powder is dispersed in an organic polymer material containing a solvent is applied, and then dried and cured to form the A dielectric layer forming step of forming a dielectric layer; an ultraviolet ray irradiating step of irradiating the dielectric layer with ultraviolet rays to modify the surface of the dielectric layer into a state in which the wettability of the adhesive is improved; A second electrode fixing step of fixing the second electrode on the surface of the dielectric layer via an adhesive; and the insulator and the third electrode on the second electrode.
A main body forming step of forming a head main body by sequentially laminating electrodes.

[0015]

According to the above method, when the ion flow electrostatic recording head is manufactured, the insulating substrate on which the first electrode is formed,
After applying a dielectric paste in which a filler composed of an inorganic fine powder is dispersed in an organic polymer material containing a solvent, it is dried and cured to form a dielectric layer, and then the dielectric layer is irradiated with ultraviolet rays. As a result, the surface of the dielectric layer is modified into a state in which the wettability of the adhesive is improved. continue,
By applying an adhesive agent on the surface of the dielectric layer in this state, the adhesive agent can be applied uniformly on the entire surface of the dielectric layer.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
Will be described. 1 (A) and 1 (B) show a schematic structure of a main part of an ion flow electrostatic recording head 1 of this embodiment, 2 is an ion generating part, and 3 is an ion flow control part.

Further, the ion generating section 3 is provided with a plurality of first electrodes 4 for ion generation and a plurality of second electrodes 5 for ion generation. These first electrodes 4 and second electrodes 5 ... A dielectric layer 6 made of a dielectric material is disposed between and. The dielectric layer 6 is formed by applying a dielectric paste in which a filler made of an inorganic fine powder having a large dielectric constant is dispersed in an organic polymer material containing a solvent, and then drying and curing the paste.

The electrostatic recording head 1 is provided with an insulating substrate 7, and a plurality of first electrodes 4 ... Which extend in one direction are arranged in parallel on the insulating substrate 7. The dielectric layer 6 is provided on the surface of the insulating substrate 7 on which the first electrodes 4 are arranged.

Further, the plurality of second electrodes 5 ...
Are adhered to each other by an adhesive S on the surface opposite to the insulating substrate 7 in a direction intersecting with the first electrodes 4 ... And the matrix is formed by the first electrodes 4 ... And the second electrodes 5. Is configured. Then, the second electrodes 5 ... Are provided with openings 5a at the portions corresponding to the matrix.
... is formed.

Further, the ion flow controller 4 has a second electrode 5 ...
On the other hand, a strip-shaped third electrode 8 arranged on the side opposite to the first electrodes 4 is provided. The third electrode 8 is provided with openings 8a at positions corresponding to the matrix of the first electrodes 4 and the second electrodes 5. Further, the second electrode 5
An insulator 9 is arranged between the ... And the third electrode 8.
The insulator 9 is provided with openings 9a at portions corresponding to the openings 5a ..., 8a ... Of the second electrode 5 ... And the third electrode 8.

When the ion cartridge 1 is in operation, the matrix between the first electrodes 4 ... And the second electrodes 5 ... Is appropriately selected based on the print signal, and the first electrodes 4 corresponding to the selected matrix portion. An alternating voltage is applied between the second electrode 5 ... As a result, the openings 5a ... Of the second electrodes 5 ... Corresponding to the selected matrix portion.
Positive and negative ions are generated in the vicinity of the inside. At this time, the second
A bias voltage is applied between the electrodes 5 ... And the third electrode 8, and only the ions determined by the polarity of the bias voltage ...
Are extracted from the ions generated in the vicinity of the openings 5a ... Then, the extracted ions pass through the openings 9a of the insulator 9 and the openings 8a of the third electrode 8 to locally charge a dielectric drum (not shown). Therefore,
By selectively driving the first electrode 4 ... And the second electrode 5 ...
A dot latent image can be formed on the dielectric drum.

Next, a method of manufacturing the ion flow electrostatic recording head shown in FIGS. 1A and 1B will be described in detail. First, the first electrodes 4 ... Are formed on the insulating substrate 7 (first electrode forming step). In this case, the insulating substrate 7 has, for example, a thickness of 10
A synthetic resin material of about 0 μm, for example, a flexible insulating substrate (FPC) such as polyimide is used. Then, after a copper foil having a thickness of 9 μm is stuck on the insulating substrate 7,
Patterning is performed by etching to form the first electrodes 4 ...

Next, the dielectric layer 6 is formed between the patterns of the first electrodes 4 on the insulating substrate 7 and on the first electrodes 4 ... (Dielectric layer forming step). At the time of forming the dielectric layer 6, for example, a dielectric paste using titanium oxide as a filler and a silicone-modified polyester alkyd resin as a binder is prepared in advance. In addition to titanium oxide, barium titanate, lead zirconate, or the like is used as the inorganic fine powder having a large dielectric constant of the filler.

This dielectric paste is the first paste on the insulating substrate 7.
It is applied, for example, by screen printing between the patterns of the electrodes 4 and on the first electrodes 4. Then, the applied dielectric paste is heated, for example, at 100 ° C. for 1 hour to volatilize and remove the solvent contained in the dielectric paste, and then, it is further cured by heating at 150 ° C. for 5 hours. ), The dielectric layer 6 having a thickness of 33 μm, for example, is formed.

Next, an ultraviolet irradiation step is performed in which the dielectric layer 6 is irradiated with ultraviolet rays to modify the surface 6a of the dielectric layer 6 to a state in which the wettability of the adhesive is improved. In this process, a batch type closed type ultraviolet reformer is used. This ultraviolet ray reforming device is a device for accommodating a predetermined amount of an object to be irradiated all together in the apparatus, and irradiating the object to be irradiated with ultraviolet rays in a state where the inside of the apparatus is sealed to make the internal air into ozone and treating it.

During operation of the ultraviolet reforming device, the low-pressure mercury lamp in the device emits 365 nm, 2
53.7 nm and 184.9 nm UV light for 5 minutes,
The entire surface 6a of the dielectric layer 6 is uniformly irradiated. At this time, the air inside the apparatus is ozonized, and the surface temperature of the dielectric layer 6 is maintained at 150 ° C. or lower in the atmospheric gas of this ozone. By the operation of this ultraviolet modifying device, the surface 6a of the dielectric layer 6 is modified into a state in which the wettability of the adhesive is improved.

Further, after modifying the surface 6a of the dielectric layer 6, the acrylic anaerobic adhesive S such as "LI-504" (trade name) manufactured by Nippon Loctite Co., Ltd., which is diluted three times with acetone, is used. Is applied to the surface 6a of the dielectric layer 6 and the surface of the insulating substrate 7 by the dipping method so that the film thickness becomes 4 μm as shown in FIG. Then, the adhesive S is heated and dried at 60 ° C. for 1 minute to volatilize the acetone,
To remove.

Then, the dielectric layer 6 in the electrode plate is formed by previously patterning the pattern of the second electrodes 5 ... And the openings 5a ... On a stainless steel foil having a thickness of 30 μm, for example.
For example, "Primer N" (trade name) P manufactured by Nippon Loctite Co., Ltd. is spray-coated on the surface of the bonding surface side with and is dried at room temperature. Then, this electrode plate is covered on the surface 6a of the dielectric layer 6 so that the plurality of first electrodes 4 ... And the openings 5a of the second electrodes 5 correspond to each other as shown in FIG. 2 (C). The second electrodes 5 are fixed on the dielectric layer 6 by pressure bonding with the second electrodes 5 arranged on the dielectric layer 6 (second electrode fixing step).

Next, the adhesive S remaining in the openings 5a of the second electrodes 5 ... Is ultrasonically cleaned with ether and removed. Thereafter, the adhesive S is heated and cured at 90 ° C. for 1 hour, and the solvent component is volatilized and dried.

Then, on the second electrodes 5 ...
A main body forming step of forming the head main body of the ion flow electrostatic recording head 1 by sequentially stacking the third electrodes 8 is performed. In this main body forming step, a photosensitive insulating film (solder resist) having a thickness of, for example, about 100 μm for forming the insulating layer 9 on the second electrodes 5 is vacuum laminated. After that, the photosensitive insulating film is subjected to photoetching treatment such as exposure and development so that the openings 5 of the plurality of second electrodes 5 ...
An opening 9a corresponding to a ... Is formed.

Further, the insulating layer 9 thus formed
The third electrode 8 having the openings 8a ... Corresponding to the openings 5a of the second electrodes 5 ... In this case, the openings 8a ...
In a state where the adhesive is applied to a portion other than the area where the adhesive 8 is applied and cured by heating, the openings 8a of the third electrode 8 are positioned and overlapped with the openings 5a of the second electrode 5 ... The ion flow electrostatic recording head 1 is manufactured by being bonded.

Therefore, according to the above method, titanium oxide is used as a filler and silicone-modified polyester alkyd resin is used as a binder on the insulating substrate 7 on which the first electrodes 4 are formed when the ion flow electrostatic recording head 1 is manufactured. After the dielectric paste is applied, the dielectric layer 6 is dried and cured to form the dielectric layer 6, and then the surface 6a of the dielectric layer 6 is irradiated with ultraviolet rays, so that the surface 6a of the dielectric layer 6 is coated with an adhesive. The wettability can be improved.

In this case, the surface 6a of the dielectric layer 6 is irradiated with 365 nm, 253.7 nm and 184.9 n.
The ultraviolet light of the wavelength of m activates oxygen molecules to generate ozone and activated oxygen in an atomic state, and -C-C-
The bond, -C-H bond, etc. are cleaved to generate activated -C. And activated oxygen and activated -C * couple | bond together and polar groups, such as -COO- and -C = 0, are produced | generated. In addition, since the energy is low in ultraviolet rays having a wavelength of 254 nm or more, for example, 365 nm, the effect of generating polar groups is low.

Then, 365 is formed on the surface 6a of the dielectric layer 6.
by irradiating ultraviolet rays having wavelengths of 25 nm, 253.7 nm and 184.9 nm to the surface 6a of the dielectric layer 6-
A polar group due to oxidation such as COOH, -CO, -OH is introduced, the compatibility with the adhesive is increased, and the wettability of the adhesive can be improved.

Therefore, when the adhesive S is applied thinly to the surface 6a of the dielectric layer 6 to a thickness of about 5 μm or less, the adhesive S may repell on the surface 6a of the dielectric layer 6 as in the conventional case. Therefore, after that, when the acrylic anaerobic adhesive S is subsequently applied to the surface 6a of the dielectric layer 6 by the dipping method, the adhesive S is uniformly applied to the entire surface 6a of the dielectric layer 6.
Can be applied. As a result, it is possible to prevent the discharge state from the ion flow electrostatic recording head 1 from becoming non-uniform, so that it is possible to prevent variations in the amount of generated ions and improve the image quality of the electrostatic latent image. ..

Further, since the anaerobic acrylic adhesive S which is more resistant to shearing force than the pressure-sensitive adhesive can be used, the tensile shearing which acts in the later step of the process of assembling the ion flow electrostatic recording head 1 can be performed. Between the dielectric layer 6 and the second electrode 5 when a force, heat during thermal processing at about 100 ° C., or stress due to heat generation due to ion generation phenomenon during use of the ion flow electrostatic recording head 1 is applied. It is possible to make it difficult to cause the positional deviation of (1), prevent deterioration of the image quality of the electrostatic latent image, and improve the durability.

Further, FIG. 3 shows the irradiation time of the ultraviolet rays radiated on the surface 6a of the dielectric layer 6 and the wetting angle of the surface 6a of the dielectric layer 6 by using the batch type closed type ultraviolet modifier. It is the experimental result which investigated the relationship of. In this case, the larger the value of the wetting angle, the less likely the liquid attached to the surface 6a of the dielectric layer 6 spreads.

Therefore, as is apparent from FIG. 3, the numerical value of the wetting angle is as large as about 92 ° when the surface 6a of the dielectric layer 6 is not irradiated with ultraviolet rays (the irradiation time of ultraviolet rays is 0). In contrast to the surface 6a of the dielectric layer 6
The numerical value of the wetting angle of the surface 6a of the dielectric layer 6 gradually changes as the irradiation time of the ultraviolet light irradiated on the surface increases, and the surface 6a of the dielectric layer 6 is irradiated with the ultraviolet light. By doing so, it can be seen that the surface 6a of the dielectric layer 6 can be modified to a state in which the wettability of the adhesive is improved.

The solvent used when removing the adhesive S remaining in the openings 5a of the second electrodes 5 by ultrasonic cleaning is not ether but ethanol, benzene, or the like.
A solvent that dissolves the acrylic anaerobic adhesive S such as "LI-504" (trade name) manufactured by Nippon Loctite Co., Ltd., such as ethyl acetate and acetone, can be used.

Further, in the above-mentioned embodiment, the structure in which the third electrode 8 and the insulating layer 9 are bonded by the adhesive is shown. However, the third electrode 8 and the insulating layer 9 are bonded to each other, for example. The structure may be such that it is attached with a double-sided tape or is attached onto the insulator layer 9 from above the third electrode 8 with a single-sided tape.

Next, a second embodiment of the present invention will be described. Here, the first ultraviolet-modifying device used in the ultraviolet-irradiating step of irradiating the dielectric layer 6 with ultraviolet rays to modify the surface 6a of the dielectric layer 6 into a state in which the wettability of the adhesive is improved. An in-line open type ultraviolet reforming apparatus is used instead of the batch processing closed type of the embodiment.

In this in-line open type ultraviolet reforming apparatus, an object to be irradiated is introduced into the apparatus through a line belt from an inlet, and ultraviolet rays are irradiated to the object to be irradiated in the apparatus until it exits from the outlet. Is a device for converting ozone into ozone and treating it. In this case, the speed of the line belt is adjusted so that the ultraviolet irradiation amount is the same as in the batch processing type closed type ultraviolet reforming apparatus. The ion flow electrostatic recording head 1 is manufactured by the same method as in the first embodiment except for this step.

Therefore, even with the above structure, the surface 6a of the dielectric layer 6 can be modified into a state in which the wettability of the adhesive is improved by the ultraviolet irradiation step as in the first embodiment. When the adhesive S is thinly applied to the surface 6a of the dielectric layer 6 to a thickness of about 5 μm or less, there is no fear that the adhesive S will repel water on the surface 6a of the dielectric layer 6 as in the conventional case. The acrylic anaerobic adhesive S can be uniformly applied to the entire surface 6a of the layer 6. Therefore, in this case as well, it is possible to prevent the discharge state from the ion flow electrostatic recording head 1 from becoming non-uniform, so that it is possible to prevent variations in the amount of generated ions and improve the image quality of the electrostatic latent image. You can The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0044]

EFFECTS OF THE INVENTION According to the present invention, a dielectric paste in which a filler composed of an inorganic fine powder is dispersed in an organic polymer material containing a solvent is applied onto an insulating substrate having a first electrode formed thereon, and then dried. Then, it is cured to form a dielectric layer, and then the surface of the dielectric layer is irradiated with ultraviolet rays to modify the surface of the dielectric layer to a state in which the wettability of the adhesive is improved. Since the second electrode is fixed on the surface of the layer via the adhesive, the adhesive can be uniformly applied to the entire surface of the dielectric layer, and the discharge state can be made uniform to form the electrostatic latent image. The image quality can be improved.

[Brief description of drawings]

FIG. 1 shows a first embodiment of the present invention,
FIG. 1A is a vertical cross-sectional view of a main part showing a schematic configuration of an ion flow electrostatic recording head, and FIG. 1B is a cross-sectional perspective view of the ion flow electrostatic recording head.

2A and 2B show a manufacturing process of an ion flow electrostatic recording head, in which FIG. 2A is a longitudinal sectional view showing a laminated state of dielectric layers, and FIG. 2B is a state in which an adhesive is applied to the surface of the dielectric layers. 2C is a vertical cross-sectional view showing the stacked state of the second electrode.

FIG. 3 is a characteristic diagram showing the relationship between the irradiation time of ultraviolet rays with which the surface of the dielectric layer is irradiated and the wetting angle.

[Explanation of symbols]

4 ... 1st electrode, 5 ... 2nd electrode, 5a, 8a, 9a ... Opening part, 6 ... Dielectric layer, 7 ... Insulating substrate, 8 ... 3rd electrode, 9 ...
Insulator layer.

Claims (1)

[Claims] 1. A plurality of first electrodes that extend in a substantially straight line in the same direction on an insulating substrate and are arranged substantially in parallel, and extend in a direction different from the extending direction of these first electrodes. , A plurality of second electrodes that form a matrix with the first electrodes and that have openings formed in portions corresponding to the matrix, and are arranged on the side opposite to the first electrodes with respect to the second electrodes. And a third electrode having an opening formed in 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. An insulator disposed between the insulator, and an opening formed in a portion of the insulator corresponding to the matrix, wherein the first substrate is formed on the insulating substrate. Forming a first electrode, and forming the first electrode On the insulating substrate formed, after applying a dielectric paste in which a filler composed of an inorganic fine powder is dispersed in an organic polymer material containing a solvent, and then dried,
A dielectric layer forming step of curing to form the dielectric layer, and an ultraviolet ray irradiation for irradiating the dielectric layer with ultraviolet rays to modify the surface of the dielectric layer to a state in which the wettability of the adhesive is improved. A second electrode fixing step of fixing the second electrode on the surface of the dielectric layer via an adhesive, and the second electrode fixing step.
A method of manufacturing an ion flow electrostatic recording head, comprising a step of forming a head body by sequentially laminating the insulator and the third electrode on an electrode.