JPH05104728A - Production of ink jet head - Google Patents

Abstract

PURPOSE:To easily obtain a head stabilized in ink delivery characteristics by a method wherein a casting material is applied by casting on a solid layer for forming an ink flow path and an orifice surface, the casting material is cured, and the solid layer is dissolved to be removed. CONSTITUTION:Oxidized insulating layers are provided on the top and rear surfaces of a substrate 2. A resist film is provided thereon except a part to be formed into a through slot. The substrate 2 provided with the through slot is formed by etching the substrate 2 and removing the resist film. Next, an element and an electrode for generating a thermal energy for delivering ink are formed. A pattern is formed by a solid layer 5 on an ink flow path- corresponding part and a part opposed to the flow path-corresponding part across the through slot. A casting material 6 is applied by casting on the substrate 2 provided with the solid layer 5. Furthermore, a top glass plate 7 having an ink supply port 9 is bonded on the casting material 6. The parts of an orifice, an ink flow path, and a top are masked, and the casting material are cured. Thereafter, this is cut into a head. The separated head is developed for forming an orifice. Moreover, the solid layer 5 is dissolved and removed by dipping this head in a solid layer developing liquid.

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 an ink jet head.

[0002]

2. Description of the Related Art Generally, a head used for ink jet recording has a plurality of fine orifices (ink ejection ports), an ink flow passage, a liquid chamber, and an ejection energy generating portion provided in a part of the ink flow passage.

As one of the methods for manufacturing such an ink jet head, a heater as an energy generator, an electrode for supplying power to the heater, and an oxidation resistant layer for preventing oxidation when the heater is generated are provided on a substrate. In order to protect the oxidation resistant layer from the cavitation development on the portion of the oxidation resistant layer on the heater, a cavitation resistant layer made of, for example, a metal is provided, and an organic material layer is provided on the portion other than the heater as an ink resistant layer. A method of coating a photocurable resin on a substrate and subjecting the resin film to a patterning treatment to form an ink flow path by the cured resin film is disclosed in JP-A-56-123869 and JP-A-57-4387.
Proposed by 6th grade.

[0004]

In such a manufacturing method, as disclosed in JP-A-57-43876, a head in which a silicon substrate, a cured resin film, and a glass top plate are laminated when forming an orifice surface. You must cut the tip. An orifice is formed by this cutting process, and the distance between the orifice and the heater, which has a significant effect on the discharge characteristics, is determined. However, since the cutting process is less accurate than other photolithography processes, the distance between the orifice and the heater is reduced. It is difficult to precisely control the distance, and it is difficult to manufacture a head having stable ejection characteristics. Further, there are problems that the flow path forming member is chipped or scratched due to the cutting step, which causes variations in the ejection direction and slows the ejection speed.

The present invention has been made in view of the above problems, and an object thereof is to provide a method of manufacturing an ink jet head without including a step of forming an orifice surface by cutting.

[0006]

According to the present invention, there is provided a casting method for an ink jet head which comprises at least a substrate, an orifice surface and a top plate, and which is provided with at least an ink supply port, an ink flow channel and an orifice hole as an ink liquid channel. The method comprises the steps of: forming a through-slot that becomes a part of the mold of the orifice surface on the substrate; arranging an energy generating element for ink ejection at a predetermined position on the substrate; Furthermore, a solid layer that can be dissolved and removed is placed on the part corresponding to the liquid chamber and on the part that will become part of the mold on the orifice surface. The casting material is covered and filled from above, and the top plate is joined from above. , Mask the unnecessary parts and cure the casting resin on the other parts, cut off the unnecessary parts that do not form the head, remove the uncured parts and the solid layer of the casting material. The method for producing an inkjet head is characterized by including the steps of: dissolving and removing, and providing an orifice hole at a predetermined position on the orifice surface.

According to this manufacturing method, the distance between the orifice and the energy generating element for ink ejection is determined by the solid layer forming the mold of the orifice surface (the surface on which the orifice hole is provided) and the step of forming the element. , That is, because it is substantially determined by the accuracy of the photolithography process,
The accuracy of the distance is dramatically improved as compared with the cutting process in the conventional technique, and as a result, a head having stable ejection characteristics can be manufactured, and further, the manufacturing yield can be improved. .. Further, since the orifice surface is formed not by a cutting process but by a casting method, it is possible to manufacture a head with a uniform discharge direction without causing chipping or scratches in the flow path forming member.

In the casting method of the present invention, a solid layer for forming the ink flow path, the orifice surface and the like and a casting agent for forming the ink flow path, the orifice surface and the like are used. The fixed layer has the ability to dissolve and remove even after forming a predetermined pattern by the photolithography process, and by dissolving and removing the casting agent coated and filled on the solid layer, the desired shape can be obtained. Can be composed of a casting agent. Hereinafter, the manufacturing method of the present invention will be described for each scratching step.

Step of forming through-slot which becomes a part of the mold of the orifice surface on the substrate (see FIGS. 2 and 3) In the present invention, the substrate which can be used is a substrate for semiconductor such as silicon, glass or alumina. Any material can be used without particular limitation. The through slot serves as a part of the mold on the orifice surface, and is formed in a predetermined position on the substrate with a predetermined size. The shape of the slot may be usually an elongated strip shape. It is not always necessary that the through slot penetrates the substrate, but a portion that does not penetrate in a subsequent process complicates the progress of the remaining process. As a method of forming the through-slot, another known technique suitable for each substrate, such as wet etching technique, can be used.

Step of disposing the energy generating element for ink ejection at a predetermined position on the substrate (see FIG. 4) Since the position of the through slot is determined, the position of the element is determined based on this. The element may be of thermal energy or pressure energy as long as it can generate ejection energy, and may be formed of a known material by a known photolithography means. Further, it is preferable to additionally provide an electrode for supplying the voltage of the element.

Step of disposing a solid layer that can be dissolved and removed (see FIG. 5) The solid layer is disposed in a portion corresponding to an ink liquid passage such as an ink passage or a liquid chamber.

It is not always necessary to form the solid layer in the portion corresponding to the liquid chamber, and it suffices to select whether or not to form the solid layer according to the type of head to be produced. Further, the solid layer is also arranged on a portion of the orifice surface which will be a part of the mold. That is, it is a part that faces the part corresponding to the ink liquid path across the through slot. The material forming the solid layer may be any material that can form a desired shape on the substrate by using a photolithography technique and has the capability of being dissolved and removed after formation, regardless of the chemical reaction form. A known type of photosensitive resin can be used. Further, as a usage form thereof, either a liquid resist or a dry flume resist can be used.

Steps of coating and filling a casting material and joining the top plate (see FIGS. 6 to 8) The casting material that can be used in the present invention is a material having a property of being hardened by light energy and / or heat energy. What is necessary is just to use the liquid resin which can be hardened | cured by an ultraviolet-ray, an electron beam, and heat, such as radical polymerization type, cationic polymerization type, addition polymerization type, or bridge | crosslinking type. Further, since the casting material is a material that specifically constitutes an ink liquid passage such as an ink passage wall, it is preferable that it has excellent adhesiveness to a substrate, mechanical strength, and ink resistance. Furthermore, the casting material must not readily dissolve the solid layer when coated on it.

As the top plate, glass is generally used, but other than glass, for example, plastic, metal, ceramics or the like can be used. The top plate is processed to form the ink supply port and, if necessary, the upper part of the ink liquid chamber. As the processing method, the holes and the dug portions may be formed according to a method suitable for the material. Further, when the casting material is cured by light energy, it is preferable to use a material having a light transmitting property, but when a material that does not transmit light such as metal or ceramics is used, a thermosetting type is used as the casting material. It may be cured by. The top plate can be joined by arranging it after pouring the casting material.

Step of curing the casting material by masking a predetermined portion. The casting material is cured by a curing means suitable for the casting material to be used. The mask may be formed by applying a black paint on the top plate, for example, when irradiating with light energy. The masked portion is an unnecessary portion that should be dissolved and removed in a subsequent step because the casting material hardly cures. Specifically, the portion corresponding to the orifice forming surface, the liquid chamber equivalent portion, etc. may be masked.

Step of cutting and removing an unnecessary portion that does not form a head (see FIGS. 7 and 8) The cutting means is not particularly limited.

Step of dissolving and removing the uncured portion of the casting material and the solid layer (see FIG. 9) Cleaning is performed through the ink supply port provided on the top plate. At this stage, the solid layer is dissolved and removed. Since it is difficult to complete the structure, it is better to carry out further cleaning treatment in the final process step.

Step of Providing Orifice Hole (See FIG. 1) Since the general shape of the ink jet head has been completed by the above steps, next, an orifice hole is provided at a predetermined position on the orifice surface. The orifice hole forming method may be any method such as a laser processing method as long as it has an accuracy of about ± 1 μm or less.

[0019]

The present invention will be described in detail below with reference to examples.

FIG. 1 shows an embodiment of an ink jet head manufactured according to the present invention. This head has a large number of orifices 1, and recording is performed by ink discharged from the orifices 1.

2 to 9 are explanatory views showing the manufacturing process of the present invention for manufacturing the ink jet head shown in FIG. Hereinafter, the present invention will be described in detail with reference to these drawings.

First, an oxide insulating layer having a depth of 1 μm was provided on the front and back surfaces of the silicon substrate 2 having a Miller index of (100). Next, as shown in FIG. 2, a resist film 3 is provided on both surfaces of the substrate 2 other than the portions to be the through slots, and the exposed oxide insulating layer of the substrate is etched with an etching solution such as hydrofluoric acid. Then, the substrate was further etched with a KOH aqueous solution, and then the resist film was removed to prepare a substrate having a through slot shown in FIG.

Next, as elements for generating thermal energy for ejection, SiO ₂ , HfB ₂ , and Ta20 are used.
5, a layer 4 made of Ta and an electrode (not shown) for feeding power were formed as shown in FIG.

Next, as shown in FIG. 5, a solid layer 5 was patterned on the substrate 2 by photolithography using a positive resist material containing naphthoquinone diazide derivative and orthocresol novolac resin as main components.
The formation portion of the solid layer is a portion that faces the portion corresponding to the flow path with the portion corresponding to the ink flow path and the through slot interposed therebetween.

Next, as shown in FIG. 6, a casting material 6 of epoxy resin was coated and injected onto the substrate 2 on which the solid layer was formed. Further, as shown in FIG. 7, a glass top plate 7 having an ink supply port 9 was bonded onto the casting material. This top plate 7 is dug (not shown) on the upper surface side to form a liquid chamber portion, and further, the liquid chamber portion and the through-slot are sandwiched so that light does not pass through the opposing portions of the flow path formation planned portion. So that it was coated in black. This was exposed to ultraviolet rays to cure the casting material in the orifice portion, the ink channel wall portion, and the ink channel ceiling portion. Next, the lines 8-1, 8-2, 8-of FIG.
Cut 3. At this time, the line 8-3 must be cut carefully so as not to cut the casting material in the orifice portion.

Next, the head separated as described above was developed using a developing solution. At this time, not only the uncured casting material in the liquid chamber portion but also the solid layer in the portion facing the ink flow path corresponding portion across the ink flow path corresponding portion and the through slot is removed at the same time. However, the solid layer corresponding to the ink flow path cannot be completely removed at this stage.
Further, at this time, since the contact area between the orifice portion and the casting material is small, the substrate in the portion corresponding to the ink flow path corresponding portion across the through slot is also dropped from the head. The above steps are shown in FIGS. FIG. 8 is a cross-sectional view taken along the line AB of FIG. 5 and FIG. 7 including the ink flow path wall. It should be noted that a release agent may be applied to the through-slot before filling the casting material in order to ensure that the substrate in the opposing portion of the ink flow path-corresponding portion is removed by sandwiching the through-slot. Further, the dropping of the substrate is not essential for the present invention, and the substrate may remain attached to the casting material of the orifice portion. Further, the solid layer of the casting agent need not be removed at the same time, and may be removed by using different developing solutions.

Next, the orifice 1 was formed by a laser processing method. Further, this head was dipped in a solid layer developing solution and subjected to ultrasonic cleaning treatment to dissolve and remove all the solid layer in the flow channel portion to complete the ink flow channel portion and the orifice portion.

Recording was carried out by mounting an electric system and an ink supply system on the ink jet head manufactured as described above, and as a result, there was very little variation in the ejection characteristics due to each flow path / heater, and the ejection direction was also different. We were able to perform uniform printing. Example 2 A resist film was provided on both sides of a 7059 glass substrate manufactured by Corning Co., Ltd. on portions other than portions to be through-slots.
Etching was performed with an etching solution such as hydrofluoric acid, and then the resist film was removed to prepare a substrate having through slots.

After this, as in Example 1, film formation of the heat energy generating element and electrode, formation of a solid layer, coating of the casting material, bonding of the glass top plate, exposure curing of the casting material, cutting, development treatment, An orifice was formed and a solid layer was dissolved and removed to prepare a head shown in FIG.

Recording was carried out by mounting an electric system and an ink supply system on the ink jet head manufactured as described above, and as a result, there was very little variation in the ejection characteristics due to each flow path and heater, and the ejection directions were uniform. It was possible to print. Example 3 Using a silicon substrate as in Example 1, formation of through-slots, formation of heat energy generating element and electrode, formation of solid layer, coating of casting material, bonding of glass top plate, exposure of casting material Cured. Next, as shown in FIGS. 11A and 11B, after cutting the lines 11-1, 11-2 and 11-3, the glass top plate was further cut along the line 11-4.
Thereafter, similarly to Example 1, the developing treatment, the formation of the orifice, and the dissolution and removal of the solid layer were performed to prepare the head shown in FIG.

Recording was carried out by mounting an electric system and an ink supply system on the ink jet head manufactured as described above, and as a result, there was very little variation in the ejection characteristics due to each flow path and heater, and the ejection directions were uniform. It was possible to print. In addition, since there is no eaves-shaped portion around the orifice, it was possible to easily clean the orifice surface.

[0032]

As described above, according to the method of manufacturing an ink jet head by the casting method of the present invention, the distance between the orifice and the energy generating element for ejecting ink can be set with high accuracy. A head with stable ejection characteristics can be easily obtained. Further, since the cutting means is not used on the surface where the orifice is formed, a head having a regular ejection direction can be obtained without causing scratches or chips. Furthermore, the method of the present invention is very useful in practice, such as improving the production yield.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an example of an inkjet head manufactured in Example 1 of the present invention.

FIG. 2 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a diagram in which a resist film for forming a through slot is formed.

FIG. 3 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a view in which a through slot is formed.

FIG. 4 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a diagram in which ejection energy generating elements are arranged.

5 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a diagram in which a solid layer is formed at a predetermined position.

FIG. 6 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a diagram in which a casting material is covered and filled.

7 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a diagram in which a top plate is joined and a casting material is cured.

8 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is an end view taken along the line AB of FIG.

9 is a schematic perspective view showing each step of the method performed in Example 1 for manufacturing the inkjet head shown in FIG. 1, and is a view in which an unnecessary portion is cut and removed.

FIG. 10 is a schematic perspective view of the inkjet head manufactured in Example 2.

11A and 11B are schematic views of an inkjet head manufactured in Example 3, FIG. 11A is a perspective view in which a top plate is joined and a casting material is cured, and FIG. It is a figure.

FIG. 12 is a schematic diagram of an inkjet head manufactured in Example 3, and is a completed perspective view.

[Explanation of symbols]

 1 Orifice 2 Substrate 3 Through-Slot Forming Resist Film 4 Discharge Energy Generation Element 5 Solid Layer 6 Casting Material 7 Glass Top Plate 8 Cutting Line 9 Ink Supply Port 10 Glass Substrate 11 Cutting Line 12 Through Slot

Claims (1)

[Claims] 1. A substrate, an orifice surface, and a top plate, which are at least formed, and serve as an ink liquid path, an ink supply port, an ink flow path,
A method of manufacturing an inkjet head having at least an orifice hole by a casting method, in which the step forms a through-slot which becomes a part of a mold of an orifice surface in an ink at a predetermined position of the substrate. Disposing the energy generating element for discharge, arranging a solid layer that can be dissolved and removed on the portion corresponding to the ink flow path or the liquid chamber and the portion that becomes a part of the mold on the orifice surface. Covering, filling, and joining the top plate from above, masking the unnecessary parts and curing the casting resin in other parts, cutting and removing the unnecessary parts that do not form the head, casting material Of the ink jet head, characterized by including dissolving and removing an uncured portion and a solid layer of the ink, and providing an orifice hole at a predetermined position on the orifice surface. Manufacturing method of de.