JPH05104729A - Production of ink jet head - Google Patents

Abstract

PURPOSE:To greatly improve an accuracy by a method wherein first and second photosensitive resin members each having a photosensitive range by two or more wavelengths are separately formed on a substrate by repeating two or more light exposure patternings, and the both members are bonded to each other through a patterned photosensitive resin member for fanning an ink flow path. CONSTITUTION:A dry film photoresist photosensitive by two wavelengths is laminated on the surface of a substrate 1. This is exposed to light of a wavelength A with a photomask overlapped and further exposed to light of a wavelength B with another photomask overlapped. After the exposing operation, an uncured dry film photoresist is dissolved in a volatile organic solvent to be removed. Then, the cured photo resist film having a roughened surface is formed on the substrate 1. An ink flow path wall of a cured photoresist film is formed on a substrate 8 in similar processes to the substrate 1. The cured photo resist films on the substrates 1 and 8 are bonded by a laminator through a dry film photoresist for forming an ink pressurizing chamber This is exposed to light and cured by thermal polymerization or the like. Thereafter, ink pressure delivery elements 9 are disposed by a required number outside the substrate and cut for truing ink delivery ports.

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 ink jet head for generating a recording ink droplet used for an ink jet recording system.

[0002]

2. Description of the Related Art An ink jet head applied to an ink jet recording system generally comprises a fine ink ejection port (orifice), an ink passage and a part of the ink passage, or an ink ejection pressure generating portion provided outside a substrate. ing. Conventionally, as a method for producing such an inkjet head, for example, by cutting, photolithography, etching or the like on glass or a metal plate, or by exposing a photosensitive resin to form fine grooves, the grooves are formed. There is known a method of forming an ink passage by joining a plate to another suitable plate, or a method of forming an ink passage by sandwiching an intermediate substrate between substrates having this groove and further forming substrates having this groove. It was being done.

[0003]

However, in the head manufactured by such a conventional method, the roughness of the inner wall surface of the ink passage to be machined is too great, and it is difficult to obtain the ink passage due to the difference in etching, etc. The ink ejection characteristics of the inkjet head are likely to vary. In addition, there is a drawback that chipping or cracking of the plate is likely to occur during cutting, resulting in poor manufacturing yield.

When photolithography or etching is performed, there are many manufacturing steps, which is disadvantageous in that the manufacturing cost increases.

Further, as a problem common to the above-mentioned conventional methods, a grooved plate having a groove formed as an ink passage and a cover plate provided with an energy generating element are generally different materials and different from each other. Since the so-called wettability with respect to the ink in the passage is different, the uniformity of the ink meniscus shape at the time of ink supply, that is, refilling after the ink is ejected from the passage is lost, The connectivity of the ink ejection characteristics is impaired.

The thin-film laminated ink jet head uses a vacuum apparatus such as vapor deposition, sputtering, and CVD, and has many manufacturing steps, leading to an increase in manufacturing cost. Further, a drawback common to the above-mentioned conventional methods is a cycle. The time is long and the productivity has been declining.

Therefore, there is an eager need for development of a method of manufacturing an ink jet head having a structure that solves these drawbacks.

The present invention has been made in view of the above problems. 1. A method of manufacturing an ink jet head which is precise and has high durability and reliability and stable ejection performance. 2. The ink passage is accurate. In addition, it is also possible to provide a method for manufacturing an inkjet head having a finely processed fine structure with high yield, and a method for manufacturing an inkjet head having a multi-array fine ink discharge nozzle by a simple method. It is another object of the invention.

[0009]

The ink jet head of the present invention which achieves these objects has a photosensitive region of two or more wavelengths from an electron beam to infrared rays, and after repeating two or more exposure patterns, After having a first photosensitive resin member on a substrate having a rough surface with a step number of steps or more and a photosensitive area of two wavelengths or more from an electron beam to infrared rays, and repeating two or more exposure patterns, The second photosensitive resin member on the substrate having a rough surface formed with two or more steps is a rough surface of each of the first photosensitive resin member and the second photosensitive resin member. And an ink passage formed so that the ink passage is formed so that the ink passage is formed on the inner side of the ink passage through the patterned photosensitive resin member for forming the ink passage that communicates with the ejection port for ejecting the ink. Heh It is a manufacturing method.

[0010]

【Example】

(Example 1) Hereinafter, the present invention will be described in detail based on examples. An embodiment of the present invention will be described according to the manufacturing process shown in FIGS.

As shown in the perspective view of FIG. 1, a suitable substrate 1 of glass, ceramic, plastic, metal or the like.
After cleaning and drying the surface, dry film photoresist 2 (film thickness, about 15 to 100 microns) exposed to two wavelengths (A) heated to about 80 to 105 degrees Celsius was used. Speed of 5 to 0.4 f / min,
Laminate under pressure conditions of 1 to 3 kg / cm ² .

At this time, the dry film photoresist 2
Is fixed to the substrate surface 1A by pressure bonding, and is not peeled off from the substrate surface 1A even when a considerable external pressure is applied thereafter.

Subsequently, as shown in FIG. 2, a photomask 3 having a predetermined pattern is superposed on the dry film photoresist 2 provided on the substrate surface 1A, and then a wavelength A is applied from above the photomask 3. Exposure (arrow in the figure) is performed.

Since this pattern is very minute, the dry film photoresist 2 is minutely exposed according to this pattern. The fine pattern can be set in various ways such as a lattice shape, a dot shape, a parallel line shape, or a curved shape of a combination thereof, and is not particularly limited as long as it is fine.

Further, as shown in FIG. 3, a photomask 5 having a predetermined pattern is superposed on the dry film photoresist 2 and then exposed at a wavelength B from above the photomask 5 (indicated by an arrow in the figure). )I do.

When the exposure is performed as described above, the dry film photoresist 2 outside the areas of the patterns 3 and 5 undergoes a polymerization reaction to be cured and becomes insoluble in the solvent. On the other hand, in the figure which is not exposed, the dry film photoresist 2 which is shaded is not cured and remains soluble in the solvent.

After the exposure operation, the dry film photoresist 2 is immersed in a volatile organic solvent such as trichloroethane or methyl ethyl ketone to dissolve and remove the unpolymerized (uncured) dry film photoresist 2. As shown in FIG. 4 which is a perspective view, a hardened photoresist film 2H having a roughened surface is formed on the substrate 1.

The surface roughness is preferably 0.1 to 10 μm, which is unevenness which effectively realizes the anchor effect with the dry film photoresist 6 to be superposed later. The cured photoresist film 2H is further cured for the purpose of improving solvent resistance. As the method, it is preferable to carry out thermal polymerization (heating at 130 to 160 ° C. for about 10 to 60 minutes), irradiation with ultraviolet rays, or a combination of both.

Next, as shown in FIG. 5, the dry film photoresist 4 on the substrate 8 is exposed to two wavelengths (A, B) heated to about 80 ° C. to 105 ° C. as in the previous step. Film photoresist 4 (film thickness, about 25 to 100 microns), 0.5 to 0.4 f /
Lamination is performed on the substrate 8 at a speed of 1 minute and under a pressure of 0.1 kg / cm ² or less.

Thereafter, in the same steps as for the substrate 1, two kinds of photomasks are used to perform exposure, development and fixing by a stepper. The ink passage wall surface of the cured photoresist film 4H is roughened when removing the unpolymerized (uncured) photoresist.

Further, the surface of the cured resist film 4H in which the ink chamber is formed as shown in perspective view 6 and the cured photoresist film 2H whose surface is roughened on the substrate 1 constitute an ink pressurizing chamber. With the dry film photoresist 6 in between,
Stick with a laminator. In order to prevent the dry film photoresist 6 from sagging at the laminating pressure (1 to 3 kg / cm ² ) shown in the previous step, the laminating pressure is set to 0.1 kg / cm ² or less, or the cured photoresist film is previously set. Read the clearance of 4H thickness (15 to 100 microns) and crimp. As a result, the dry film photoresist 6 is pressure-bonded and fixed to the surfaces of the cured photoresist films 2H and 4H, and is not peeled off even when a considerable external pressure is applied thereafter.

Here, as shown in FIG. 7, the dry film photoresist 6 is mechanically punched out in advance at a low temperature in the ink pressurizing chamber portion, but the dimensional accuracy is 50 to 100.
Precision of about micron is enough.

As shown in the cross-sectional view of FIG. 8, after exposure from the top, either thermal polymerization or ultraviolet irradiation is carried out, or both are used together for curing treatment.

As described above, after the dry film photoresist 6 is hardened and the bonding between the hardened films 2H and 4H is completed, ink pressure discharge such as a piezo element is generated outside the substrate 1. A desired number of elements 9 (ink ejection energy generating elements) are arranged. Although not shown, a signal input electrode is connected to the ink ejection generation element 9.

The dicing method which is usually adopted in the semiconductor industry is adopted, and the ink discharge ports are cut to be aligned.
Then, the cut surface is polished and smoothed, and an ink tank is directly connected through the ink supply port, or an ink tank (not shown) is connected to the ink supply port, or an ink (not shown) is connected to the ink supply port. An ink supply pipe (not shown) for connecting to the tank is attached to complete the ink jet head. In the above embodiments, the photoresist film 2H corresponds to the first photosensitive resin member, the photoresist film 4H corresponds to the second photosensitive resin member, and the photoresist film 6 corresponds to the patterned photosensitive resin member. ing.

As shown in FIG. 9, a photoresist having a central sensitivity in the ultraviolet region and a photoresist having a central sensitivity in the visible light region were used for the wavelength used during the exposure.

Although a dry film type, that is, a solid type is used as the photosensitive composition (photoresist) for forming the grooves in the above-mentioned embodiments, the present invention is not limited to this, and the photoresist 2 is used. Liquid photosensitive compositions can also be used as 4, 6 and 6.

As a method for forming the photosensitive composition on the substrate, in the case of a liquid, a method using a squeegee used when producing a relief image, that is, a wall having the same height as the desired photosensitive composition film pressure is used. It is a method of removing the excess composition by placing it around the substrate and using a squeegee. in this case,
A suitable viscosity of the photosensitive composition is 100 to 300 CPS. Further, the height of the wall placed around the substrate needs to be determined in consideration of the reduction in evaporation of the solvent component of the photosensitive composition.

In addition, a liquid photosensitive resin can be applied and molded as a thin film on a substrate by a high-speed spin coater. On the other hand, in the case of a solid, the photosensitive composition sheet is heated and pressure-bonded onto the substrate to be adhered. There is a method of forming a film.

In the present invention, the method of using a semi-solid dry film type is advantageous in that the handling and thickness control can be performed easily and accurately. Examples of such a semi-solid material include, for example, ALPHO series manufactured by Nippon Synthetic Rubber Co., Ltd., Ozatech Co., Ltd. of Nippon Synthetic Chemical Industry Co., Ltd., Dialon of Mitsubishi Rayon Co., Ltd., Photec of Hitachi Chemical Co., Ltd., Sunfort of Asahi Kasei Co., Ltd., RISTON Bakurel of DuPont Co., Ltd., and Audil of Tokyo Ohka Co., Ltd. There are commercially available photosensitive resins under the trade names such as.

In liquid form, Taiyo Ink PSR series,
There are photosensitive resins that are commercially available under the trade names of Tokyo Ohka Co. PMR series and Toray Photo Nice. In addition to the above, the photosensitive composition used in the present invention includes many photosensitive materials such as photosensitive resins and photoresists which are used in the field of ordinary photolithography.

Silicone resins usable in the present invention are TSE series, YE series, and TUV of Toshiba Silicone Co.
Series, Shin-Etsu Silicone KE series, etc.

Examples of these photosensitive materials include diazoresin, p-diazoquinone, and photopolymerization type photopolymers using a vinyl monomer and a polymerization initiator, for example.
A dimerization type photopolymer using polyvinyl cinnamate etc. and a sensitizer, a mixture of orthonaphthoquinonediazide and a volatile type phenol resin, a mixture of polyvinyl alcohol and a diazo resin, 4-glycidyl ethylene oxide and benzophenone or glycidical chalcone are copolymerized. Polyether type photopolymer, copolymer of N, N-dimethylmethacrylamide and acrylamide benzophenone, unsaturated polyester photosensitive resin [eg, APR (Asahi Kasei), Tevista (Teijin), Sonne (Kansai Paint), etc. ], Unsaturated urethane oligomer photosensitive resin, photosensitive composition obtained by mixing photopolymerization initiator and polymer in bifunctional acrylic monomer, dichromic acid photoresist, non-chromium water-soluble photoresist, polyvinyl cinnamate System Torejisuto, cyclization Gomuajido based photoresist, and the like.

Examples of these photosensitive materials include diazoresin, p-diazoquinone, and photopolymerization type photopolymers using, for example, a vinyl monomer and a polymerization initiator,
A dimerization type photopolymer using polyvinyl cinnamate etc. and a sensitizer, a mixture of orthonaphthoquinonediazide and a volatile type phenol resin, a mixture of polyvinyl alcohol and a diazo resin, 4-glycidyl ethylene oxide and benzophenone or glycidical chalcone are copolymerized. Polyether type photopolymer, copolymer of N, N-dimethylmethacrylamide and acrylamide benzophenone, unsaturated polyester photosensitive resin [eg, APR (Asahi Kasei), Tevista (Teijin), Sonne (Kansai Paint), etc. ], Unsaturated urethane oligomer photosensitive resin, photosensitive composition obtained by mixing photopolymerization initiator and polymer in bifunctional acrylic monomer, dichromic acid photoresist, non-chromium water-soluble photoresist, polyvinyl cinnamate System Torejisuto, cyclization Gomuajido based photoresist, and the like.

[0035]

As described above, the effects of the present invention can be enumerated variously as follows. a. Dry film photoresists 2 and 4 to be attached
Since the positioning accuracy is the accuracy of the stepper used in the semiconductor industry regardless of the mechanical accuracy of the laminator and the rigidity of the dry film photoresists 2 and 4, a marked improvement in accuracy can be realized.

B. Since the dry film photoresists 2 and 4 that have been exposed to two layers at the time of development are processed at the same time, the sagging due to the pressure and heat treatment during the second lamination is prevented.
No pressure operation required. This is an effective method for improving workability and quality.

C. Since the uncured dry film photoresists are attached to each other, the adhesion is improved as compared with the case where the dry film photoresists are attached after curing.

D. Repeated positioning / exposure
The development process could be simplified once, and the productivity was improved, the quality was stabilized, and the yield was improved.

E. Most of the inner surface of the ink passage is made of the same material and has the same wettability with the ink, and the wall surface of the ink passage is finely roughened, so that the ink refill is fast and stable, and the ink ejection characteristics are stable. It can be improved.

In particular, according to the present invention, both the first photosensitive resin member and the patterned photosensitive resin member are bonded to each other, and the second photosensitive resin member and the patterned photosensitive member are bonded to each other. It is not limited to the bonding of conductive resins, but the rough surface formed by utilizing the photosensitivity is effectively used as the bonding surface, so that the bonding strength can be significantly improved, which is high. It can be an inkjet head having strength.

F. Since the main process of manufacturing the head is based on the so-called printing technique, it is possible to extremely easily form the head fine portion with a desired pattern. Moreover, a large number of heads having the same structure can be simultaneously processed. Continuous and mass production is possible, and the number of manufacturing processes is relatively small, so the productivity is good.

G. A high density multi-array inkjet head is obtained in a simple manner.

H. Since it is not necessary to use an etching solution (strong acids such as hydrofluoric acid), it is also excellent in safety and hygiene.

I. Since the adhesive is rarely used, the adhesive does not flow to block the groove or adhere to the ink ejection pressure generating element to cause a functional deterioration.

J. According to the method for manufacturing the ink jet head of the present invention, the shape-accurate shape of the main constituent parts on the order of micron can be realized by photolithography regardless of the accuracy of the laminator pressure, speed and temperature when forming the ink passage. Therefore, the improved ink path dimensional accuracy stabilizes the ink flight speed and ink particle size, resulting in significantly improved printing quality.

K. Dense main components of the ink jet head are formed by photolithography, and since this photolithography is performed in a clean room generally used in the semiconductor industry, dust enters inside the ink passage during the assembly of the inkjet head. Can be minimized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 3 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 4 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 5 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 6 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 7 is an explanatory view of the manufacturing process of the present invention.

FIG. 8 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 9 is an explanatory view of the manufacturing process of the present invention.

[Explanation of symbols]

1, 8 substrate 1A substrate surface 2, 4, 6 dry film photoresist 2H, 4H cured dry film photoresist film 3, 5, 7 photomask 9 ink ejection generating element

Claims (1)

[Claims] 1. Having a photosensitive region of two or more wavelengths from an electron beam to infrared rays, and repeating two or more exposure patterns,
After having a first photosensitive resin member on a substrate having a rough surface having two or more stepped surfaces and a photosensitive region of two or more wavelengths from an electron beam to infrared rays, after repeating two or more exposure patterns A second photosensitive resin member on a substrate having a rough surface having two or more stepped surfaces, the rough surface of each of the first photosensitive resin member and the second photosensitive resin member. It is characterized in that the ink passage is formed by joining the ink through a patterned photosensitive resin member for forming an ink passage communicating with an ejection port for ejecting ink so that the surface faces inward. Inkjet head manufacturing method.