JP5361498B2 - Inkjet head manufacturing method and inkjet head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method by which an inkjet head favorable in printing characteristics can be manufactured stably. <P>SOLUTION: The inkjet head is manufactured by the method which includes: a process of forming a positive resist layer on a substrate in which pressure generating elements are formed; a process of selectively coloring at least a surface of a part being an ink flow channel of the positive resist layer; a process of forming an ink flow channel pattern by patterning the positive resist layer using the colored part as a mask; a process of forming a coating resin layer being an ink flow channel forming member thereon; a process of forming delivering openings in the coating resin layer located above the pressure generating elements; and a process of dissolving and removing the ink flow channel pattern to form the ink flow channel that communicates with the delivering opening. The coloring of the positive resist layer is preferably carried out by using a dye solution or a pigment dispersion liquid after making hydrophilic a predetermined position of the positive resist layer by i-beam irradiation. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing an ink jet head, and more particularly to a method for manufacturing an ink jet head having an ink flow path formed with high accuracy and high density. Furthermore, the present invention relates to an ink jet head capable of accurately ejecting small droplets of ink.

  An ink jet head applied to an ink jet recording system generally includes an ink flow path, a discharge energy generation unit provided in a part of the ink flow path, and a fine ink discharge port for discharging ink by the energy of the discharge energy generation unit And. This ink discharge port is called an “orifice”.

  As a method of manufacturing such an ink jet head, Patent Document 1 discloses the following method of manufacturing an ink jet head. The manufacturing method will be described with reference to FIG. 3 (FIGS. 3A to 3B). First, a positive resist layer 3 made of a positive resist that is a photosensitive resin material is formed on a substrate 1 (FIG. 3A) on which a pressure generating element 2 as an ejection energy generating element is formed (FIG. 3). 3 (b)). Next, light having a wavelength capable of reacting with the positive resist is irradiated through the first mask 4 (FIG. 3C), and development processing is performed to form a desired ink flow path pattern 5 (FIG. 3). (D)). Subsequently, a coating resin layer 6 serving as a nozzle material is applied and formed on the ink flow path pattern 5 (FIG. 3E), and pattern exposure is performed through a second mask (reticle) 7 (FIG. 3F). )), Development processing is performed to form the ink ejection port 8 (FIG. 3G). Further, an ink supply port 9 penetrating the substrate 1 is formed (FIG. 3 (h)), and the ink flow path pattern 5 is dissolved and removed to form the ink flow path 10 (FIG. 3 (i)). In this manufacturing method, since a semiconductor photolithography technique is applied, it is possible to perform very fine processing with extremely high accuracy with respect to the formation of ink flow paths, discharge ports, and the like.

Japanese Patent Laid-Open No. 06-286149

  In the ink jet head manufacturing method described above, the coating resin layer 6 for forming the ink flow path needs to be formed on the ink flow path pattern 5, so that the coating resin layer 6 is applied to the positive resist. Resistance to solvents is required. Therefore, as the positive resist material, a polymer main chain decomposition resist mainly composed of polyketone or acrylic resin having excellent solvent resistance is generally used.

When these main chain decomposition type resists are used in a relatively thick film thickness, a so-called stepper that irradiates light of a single wavelength with a reduction projection optical system is often not used for the exposure. Instead, it is common to use a proximity type exposure apparatus that collectively exposes the entire substrate with broad light at a 1: 1 magnification from the viewpoint of photosensitive wavelength and sensitivity. However, when exposure is performed using a proximity type exposure apparatus, the following problems may occur.
1) When a large wafer of about 8 to 12 inches is exposed, it is affected by the warpage of the substrate and the deflection of the mask, so that the alignment accuracy may vary between and between the substrates.
2) When exposing a resist having a thickness of about 10 μm, it is necessary to irradiate a large amount of energy in order to cause a sufficient decomposition reaction. For this reason, the mask and the substrate may cause non-uniform thermal expansion due to heat generated during exposure, and resolution and alignment accuracy may deteriorate.

  In the above exposure process, the exposure of the positive resist and the coating resin layer is generally performed with reference to an alignment mark formed on the substrate. However, when the above-described problem occurs, the positional relationship between the pressure generating element and the ink flow path pattern made of a positive resist, and further, the positional relationship between the ink flow path pattern and the ejection port is what is desired. The problem of being different arises. FIG. 4 is a schematic diagram showing a state in which the misalignment has occurred. When such misalignment occurs, it may lead to troubles such as misalignment in the ink ejection direction and a large amount of satellites, resulting in poor print characteristics.

  As a result of intensive studies aimed at solving the above problems, the present inventors have made the following invention.

That is, the present invention includes a step of forming a positive resist layer formed of a material that exhibits or improves hydrophilicity by light irradiation on a substrate on which a pressure generating element is formed;
Irradiating the positive resist layer with light to form a light irradiation portion on the surface of the positive resist layer;
A step of selectively coloring at least a surface of a portion serving as an ink flow path in the light irradiation portion of the positive resist layer to form a colored portion in the positive resist layer ;
Patterning the positive resist layer using the colored portion of the positive resist layer as a mask to form an ink flow path pattern; and
Forming a coating resin layer serving as an ink flow path forming member on the substrate on which the ink flow path pattern is formed;
Forming a discharge port in the coating resin layer located above the pressure generating element;
And a step of dissolving and removing the ink flow path pattern to form an ink flow path communicating with the discharge port.

  Moreover, this invention is the inkjet head manufactured by the manufacturing method of the said inkjet head.

  By using the ink jet head manufacturing method according to the present invention, it is possible to stably manufacture an ink jet head having good printing characteristics.

It is a perspective view which shows the structure of an inkjet head. It is sectional drawing for demonstrating the manufacturing method of the inkjet head which concerns on this invention. It is sectional drawing for demonstrating the manufacturing method of the inkjet head which concerns on this invention. It is sectional drawing for demonstrating the manufacturing method of the inkjet head which concerns on this invention. It is sectional drawing for demonstrating the manufacturing method of the inkjet head which concerns on a prior art. It is sectional drawing for demonstrating the manufacturing method of the inkjet head which concerns on a prior art. It is a schematic diagram which shows the state which alignment misalignment generate | occur | produced. It is a schematic diagram showing a method for evaluating the positional relationship of ink flow paths.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 schematically shows a perspective view of an inkjet head. Hereinafter, the manufacturing method of the ink jet head of the present invention will be described according to the manufacturing flow shown in FIG. 2 (FIGS. 2A to 2C), using a schematic cross-sectional view when the ink jet head of FIG. 1 is cut along line AB. To do.

1. Preparation of substrate (Fig. 2 (a))
First, in the present invention, as shown in FIG. 2A, a substrate 1 on which a pressure generating element 2 is formed is prepared. As long as the substrate 1 functions as a part of the ink flow path constituent member and can function as a support for a material layer that forms the ink flow path 10 and the discharge port 8 described later, the shape, material, etc. Although not particularly limited, a silicon substrate is generally used.

  A desired number of pressure generating elements 2 such as electrothermal conversion elements or piezoelectric elements are arranged on the substrate 1. By such a pressure generating element 2, ejection energy for ejecting ink droplets is given to the ink, and recording is performed. For example, when an electrothermal conversion element is used as the pressure generating element 2, the element heats nearby ink to cause a state change in the ink, and ink ejection energy is generated. For example, when a piezoelectric element is used as the pressure generating element 2, ink ejection energy is generated by mechanical vibration of the element.

  These pressure generating elements 2 are connected to control signal input electrodes (not shown) for operating the elements. Further, in general, a protective layer (not shown) for the purpose of improving the durability of the pressure generating element 2, an adhesion improving layer (not shown) for the purpose of improving the adhesion with a nozzle constituent member described later, etc. Various functional layers are provided, but such functional layers may be provided in the present invention.

2. Formation of positive resist layer (FIG. 2B)
Next, as shown in FIG. 2B, a positive resist layer 11 is formed on the substrate 1 on which the pressure generating element 2 is formed. As the positive resist used here, a chemically amplified positive photoresist using a photoacid generator is preferably used. In particular, in the present invention, it is preferable to perform patterning using a stepper (reduction projection exposure apparatus) from the viewpoint of alignment accuracy, and it is preferable to perform patterning with the most general i-line (365 nm). It is preferable to have a zone. As a resist satisfying these requirements, it is preferable to use a novolak resin, polyhydroxystyrene, and a polymer that can be developed with an alkali based on a polymer thereof.

  In particular, it is preferable to use a material whose hydrophilicity is expressed or improved by light irradiation so as to be colored more effectively because it is selectively colored with a dye solution or a pigment dispersion in the coloring step described later. Examples thereof include novolak resin, polyhydroxystyrene, and polymers thereof having a substituent in which a hydroxyl group or a carboxyl group is blocked with a hydrolyzable protecting group. As an example, when the polymer (polyhydroxystyrene) represented by the following general formula (A) is used in combination with a photoacid generator, the tert-butoxycarbonyl group is eliminated by the acid generated by light irradiation, and the phenolic hydroxyl group is removed. By generating, hydrophilicity is expressed. Moreover, it functions as a positive resist that can be developed with an alkali using this hydrophilization and hydrophobization.

(N and m are integers)
The positive resist layer 11 can be formed by a known coating method such as spin coating, roll coating, or slit coating. Alternatively, a dry film material may be used and a lamination method may be used.

3. Exposure of flow path forming mask (FIG. 2 (c))
Next, as shown in FIG. 2C, the positive resist layer 11 is subjected to pattern exposure through a first reticle (mask) 12 and baked. By doing so, an acid is generated from the photoacid generator in the exposed portion, and the protecting group for the —OH group is eliminated, so that the exposed portion becomes hydrophilic.

4). Coloring process (FIG. 2 (d))
Next, as shown in FIG. 2 (d), at least the surface of the portion that becomes the ink flow path that is the exposed portion (light irradiation portion) of the positive resist layer 11 is selectively colored to form the dyed pattern 13. .

  As will be described later, the dyed pattern 13 functions as a mask for exposing the positive resist layer 11 and needs to be able to block light in the photosensitive wavelength region of the positive resist layer 11. Therefore, it is preferable to dye with a dye or pigment having strong absorption with respect to the photosensitive wavelength region of the positive resist layer 11. The thickness of the dyeing pattern can be adjusted by adjusting the exposure amount during light irradiation and the conditions of the subsequent heat treatment (Post Exposure Bake).

  Since the dye or pigment needs to penetrate or bond to the exposed area to make the exposed area insoluble in alkali, the dye (compound) having a structure represented by any of the following general formulas (1) to (3) Is preferred. In particular, a dye containing two or more structures represented by any of the following general formulas (1) to (3) may be able to strongly hydrophobize the positive resist layer 11 and improve process resistance. More preferred.

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each independently represents an unsaturated hydrocarbon group or a substituted or unsubstituted aromatic group. A ₁ represents hydrogen or a halogen element. ]
Examples of substituents for R _{1 to} R ₄ include benzophenone derivatives, thioxanthone derivatives, quinone derivatives such as naphthoquinones and anthracene, anthracene derivatives, and the like. Further, substituents other than the above substituents can be used as long as they do not depart from the gist of the present invention. Examples of the halogen element that becomes A ₁ include fluorine, chlorine, bromine, iodine, and astatine.

  Since the ink flow path pattern 14 is obtained by using the dyed portion as a mask, and absorption at i-line (365 nm) is required when forming the discharge port 8 to be described later, a red dye is particularly effective.

  As a solvent for dissolving the dye, it is preferable to use a mixed solvent of water and an organic solvent for the purpose of improving permeability to the positive resist layer 11 instead of water alone. Examples of the organic solvent include alkyl alcohols having 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol; dimethylformamide, dimethylacetamide Amides such as acetone, ketones such as acetone and diacetone alcohol, or ethers such as tetrahydrofuran and dioxane, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, ethylene glycol, propylene glycol, butylene glycol, and triethylene Alkylene glycols having 2 to 6 carbon atoms in alkylene groups such as glycol, thiodiglycol, hexylene glycol, and diethylene glycol Glycerins; lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl ether, diethylene glycol methyl ether and triethylene glycol monomethyl ether; pyrrolidones such as N-methyl-2-pyrrolidone and 2-pyrrolidone; Two or more kinds can be mixed and used.

  Examples of the pigment include carbon black and titanium black, which can obtain a high light-shielding property for a wide range of wavelengths with a small amount. In particular, carbon black is preferably used, and channel black, furnace black, thermal black, lamp black, and the like can be dispersed in water or the organic solvent described above. Further, for the purpose of improving the dispersibility in the positive resist layer 11, resin-coated carbon black may be used. At this time, if the covering resin is a compound containing a structure represented by any of the following general formulas (1) to (3), there is a possibility that the positive resist layer 11 can be more strongly hydrophobized. In order to improve process tolerance, it is more preferable.

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each independently represents an unsaturated hydrocarbon group or a substituted or unsubstituted aromatic group. A ₁ represents hydrogen or a halogen element. ]
Moreover, when dyeing the positive resist layer 11 using these coloring liquids, the solution or the substrate to be processed may be heated as necessary. Further, after dyeing, the dye or pigment may be fixed more firmly in the positive resist layer 11 by performing treatments such as washing with water and heating as necessary.

5. Formation of ink flow path pattern (FIGS. 2E and 2F)
Next, using the dyed pattern 13 as a mask, light in a wavelength region capable of exposing the non-colored portion of the positive resist layer 11 is irradiated (FIG. 2E). Then, development processing is performed to pattern the positive resist layer 11 to form an ink flow path pattern 14 made of a positive resist (FIG. 2F).

  A method of forming two resin layers, patterning the upper resin layer into a desired shape, and then transferring the upper layer pattern to the lower resin layer using the pattern as a mask is known as a so-called two-layer resist method. Yes. In particular, a method in which a positive photoresist is used for the lower layer, an upper mask is made of a material that shields the photosensitive wavelength of the lower layer, and the lower layer is patterned is known as a PCM (Portable Conformable Mask) method (special feature). No. 63-58367).

  In the present invention, this method is applied to the manufacture of an ink jet head, and the positive resist layer 11 is patterned by providing a direct mask in the positive resist layer 11 for forming the ink flow path 10. By doing so, it is possible to avoid the phenomenon that the mask and the substrate cause non-uniform thermal expansion, which has been a problem in the past, and the resolution and alignment accuracy deteriorate.

6). Formation of discharge port (FIG. 2 (g), FIG. 2 (h), FIG. 2 (i))
Next, the coating resin layer 6 is formed on the ink flow path pattern 14 by a method such as spin coating, roll coating, or slit coating (FIG. 2G). Since this coating resin layer functions as an ink flow path forming member, high mechanical strength as a structural material, adhesion to the ground, and ink resistance are simultaneously patterned. Therefore, resolution and the like are required. As a material for forming the coating resin layer satisfying these characteristics, a cationic polymerization type epoxy resin composition is suitable.

  Examples of the epoxy resin used in the cationic polymerization type epoxy resin composition include a reaction product of bisphenol A and epichlorohydrin having a molecular weight of about 900 or more, a reaction product of bromobisphenol A and epichlorohydrin, phenol novolac, Reaction product of o-cresol novolak and epichlorohydrin, oxycyclohexane described in JP-A-60-161973, JP-A63-221121, JP-A-64-9216, JP-A-2-140219 Examples thereof include polyfunctional epoxy resins having a skeleton, but are not limited to these compounds.

  Moreover, as said epoxy resin, a compound whose epoxy equivalent is 2000 or less is preferable, and a compound whose epoxy equivalent is 1000 or less is more preferable. When a compound having an epoxy equivalent of more than 2000 is used, the crosslinking density is lowered during the curing reaction, which may cause problems in adhesion and ink resistance.

  As the photocationic polymerization initiator that is added to the cationic polymerization type epoxy resin composition and cures the epoxy resin, a compound that generates an acid by light irradiation can be used. The compound that generates an acid by light irradiation is not particularly limited, and examples thereof include aromatic sulfonium salts and aromatic iodonium salts. As the aromatic sulfonium salt, TPS-102, 103, 105, MDS-103, 105, 205, 305, DTS-102, 103 (all trade names) commercially available from Midori Chemical Co., Ltd., SP-170 and 172 (both trade names) commercially available from Asahi Denka Kogyo Co., Ltd. can be suitably used. Moreover, as an aromatic iodonium salt, DPI-105, MPI-103, 105, BBI-101, 102, 103, 105 (all are brand names) etc. which are marketed from Midori Chemical Co., Ltd. are used suitably. Can do. The addition amount of the cationic photopolymerization initiator can be an addition amount that achieves the target sensitivity, but can be suitably used in the range of 0.5 to 5 wt% with respect to the epoxy resin. Moreover, you may add and use SP-100 (brand name) etc. which are marketed from Adeka Co., Ltd. as a wavelength sensitizer as needed.

  It is possible to appropriately add additives and the like to the epoxy resin composition as necessary. For example, a flexibility-imparting agent can be added for the purpose of lowering the elastic modulus of the epoxy resin, or a silane coupling agent can be added in order to obtain further adhesion to the base.

  Next, an ink repellent agent layer having negative photosensitivity is formed on the coating resin layer 6 as necessary (not shown). The ink repellent agent layer can be formed by a coating method such as a spin coating method, a roll coating method, or a slit coating method, but in this example, both are necessary because they are formed on the uncured coating resin layer 6. Avoid miscibility.

  Next, pattern exposure is performed through a second reticle (mask) 15 using an i-line stepper similar to that used for exposure of the positive resist layer 11 (FIG. 2H). Thereafter, development processing is performed to form the discharge port 8 in the coating resin layer 6 located above the pressure generating element 2 (FIG. 2 (i)).

  In the manufacture of an ink jet head, in addition to the ink flow path pattern 14 described above, it is a very important factor to pattern the discharge ports 8 with high accuracy. Therefore, it is desirable to use a stepper having high accuracy and high illuminance as the exposure apparatus for exposure of the coating resin layer 6 for forming the discharge port 8.

  However, when a single wavelength of i-line (365 nm) is used for the irradiation light of the coating resin layer 6 for forming the discharge port 8, the desired pattern of the discharge port 8 depends on the pattern shape of the pressure generating element 2 and the shape of the wiring pattern. The shape may not be obtained. For example, even when a circular mask is used as the pattern mask for the discharge port 8, the pattern of the discharge port 8 that is actually formed may be a distorted circular shape, which is stably reproduced as the shape of the discharge port 8. A circular shape may not be obtained with good performance.

  This problem is caused when the coating resin layer 6 for forming the ejection port 8 or the resist material for forming the ink flow path pattern 14 located under the ejection port 8 is weakly absorbed by the i-line, and the surface of the substrate 1 or pressure This is considered to be because the reflected light from the surface of the generating element 2 and the wiring is affected. It is clear that this problem occurs particularly when the density of the inkjet head is increased and the size of the discharge port and the ink flow path is reduced. The high-quality and high-performance of the inkjet head and its printed matter It has become an important issue toward the realization.

In the present invention, since the dyed pattern 13 remains on the surface layer of the ink flow path pattern 14, light is absorbed by the dyed pattern 13 even when the wavelength of the i-line alone is used, and the pattern of the pressure generating element 2. And reflection from the wiring pattern can be prevented. As a result, it is possible to solve the problem that the desired pattern shape of the ejection port 8 cannot be obtained due to the influence of the reflected light.
7). Formation of ink supply port and ink flow path (FIG. 2 (j), FIG. 2 (k))
Next, an ink supply port 9 penetrating the substrate 1 is formed (FIG. 2 (j)). The ink supply port 9 can be formed by a method such as sandblasting, dry etching, wet etching, or a combination of these methods.

  For example, anisotropic etching using an aqueous solution of potassium hydroxide, sodium hydroxide, tetramethylammonium hydroxide or the like, which is an alkaline etching solution, will be described. Silicon substrates having <100> and <110> orientations as crystal orientations can be selectively etched in the depth direction and the width direction with respect to the direction of etching by performing alkaline chemical etching. Can be obtained. In particular, the etching depth of a silicon substrate having a <100> crystal orientation can be controlled because the etching depth is geometrically determined by the etching width. For example, it is possible to form a hole that narrows with an inclination of 54.7 ° in the depth direction from the etching start surface. The ink supply port 9 penetrating the substrate 1 can be formed by performing the above-described anisotropic etching using an appropriate resin material resistant to the etching solution as a mask.

  Next, if necessary, light having a photosensitive wavelength of the positive resist layer 11 is irradiated from the upper surface of the coating resin layer 6 (not shown), and the ink flow path pattern 14 is dissolved and removed, whereby ink communicating with the ejection port 8 is obtained. The flow path 10 is formed (FIG. 2 (k)). Further, after a cutting and separating step (not shown), heat treatment is performed as necessary to completely cure the coating resin layer 6, joining of a member (not shown) for supplying ink, and the pressure generating element 2. Electrical connection (not shown) for driving is performed to complete the ink jet head.

  By using the ink jet head manufacturing method of the present invention as described above, the positional relationship among the pressure generating element, the ink flow path and the ejection port can be controlled with high accuracy and good reproducibility. Further, since the discharge port is not deformed, an ink jet head with good printing characteristics can be manufactured stably.

  The above method is not limited to the method of manufacturing the ink jet head, and is also effective as a pattern forming method for forming a pattern on the substrate to be processed.

  Examples of the present invention are shown below.

Example 1
An ink jet head was manufactured according to the process shown in FIG. First, a substrate 1 as shown in FIG. 2A was prepared. Generally, since a driver, a logic circuit, and the like that control the pressure generating element 2 are manufactured by a general-purpose semiconductor manufacturing method, it is preferable to apply a silicon substrate. In this example, an electrothermal conversion element (heater made of material HfB ₂ ) as a pressure generating element on an 8-inch silicon substrate, and a laminated film (not shown) of SiN + Ta in the ink flow path and the nozzle formation site. A silicon substrate was prepared.

Next, as shown in FIG. 2 (b), a resin composition having the following composition as a positive resist is spin-coated on the substrate 1 on which the pressure generating element 2 is formed, and baked at 90 ° C. for 3 minutes. As a result, a positive resist layer 11 was formed. The film thickness after baking of the positive resist layer 11 was 12 μm.
40 parts by mass of polyhydroxystyrene represented by formula (A) (n: m = 4: 6, average molecular weight (Mw): 20000)
Photoacid generator (manufactured by ADEKA, trade name: SP-172) 2 parts by mass diglyme 60 parts by mass Next, as shown in FIG. 2C, an i-line stepper (manufactured by Canon, trade name: i5) is used. It was exposed at an exposure amount of 200 J / m ² through the first reticle (mask) 12 and heat-treated at 90 ° C. for 3 minutes. Next, a colored liquid having the following composition was spin-coated and baked at 120 ° C. for 5 minutes to form a dyed pattern 13 (FIG. 2D).
・ 2-Benzophenone-4,4′-dicarboxylic acid 30 parts by mass ・ Diethylene glycol 30 parts by mass ・ Ion-exchanged water 40 parts by mass Subsequently, as shown in FIG. Name: UX-3200) was exposed at an exposure amount of 15000 mJ / cm ² and heat-treated at 90 ° C. for 10 minutes. Thereafter, the positive resist was developed using a 2.38 wt% tetramethylammonium hydroxide aqueous solution to form an ink flow path pattern 14 (FIG. 2F).

Next, a photosensitive resin composition having the following composition is spin coated on the substrate to be processed so that the film thickness on the ink flow path pattern 14 is 10 μm, and prebaked at 90 ° C. for 2 minutes on a hot plate. The covering resin layer 6 was formed (FIG. 2 (g)).
-EHPE (trade name, manufactured by Daicel Chemical Industries) 100 parts by mass-SP-172 (trade name, manufactured by ADEKA) 5 parts by mass-A-187 (trade name, manufactured by Nihon Unicar) 5 parts by mass-100 parts by mass of methyl isobutyl ketone Subsequently, a photosensitive resin composition having the following composition is spin-coated on the substrate to be treated so as to have a film thickness of 1 μm, and prebaked on a hot plate at 80 ° C. for 3 minutes to form an ink repellent layer. (Not shown) was formed.
-EHPE (trade name, manufactured by Daicel Chemical Industries) 35 parts by mass-2,2-bis (4-glycidyloxyphenyl) hexafluoropropane 25 parts by mass-1,4-bis (2-hydroxyhexafluoroisopropyl) benzene 25 parts by mass Parts · 3- (2-perfluorohexyl) ethoxy-1,2-epoxypropane 16 parts by mass · A-187 (trade name, manufactured by Nihon Unicar) 4 parts by mass · SP-172 (product name, manufactured by ADEKA) 5 parts by mass Part / diethylene glycol monoethyl ether 100 parts by mass Next, after pattern exposure at an exposure amount of 4000 J / m ² through a second reticle (mask) 15 using an i-line stepper (product name: i5) manufactured by Canon (FIG. 2 (h)), PEB was performed at 120 ° C. for 120 seconds on a hot plate. Thereafter, development with methyl isobutyl ketone, rinsing with isopropyl alcohol, and heat treatment at 100 ° C. for 60 minutes were performed to form the discharge port 8 (FIG. 2I). In this example, a discharge port pattern of φ13 μm was formed.

  Next, an etching mask (not shown) having an opening shape with a width of 1 mm and a length of 10 mm was prepared on the back surface of the substrate to be processed using a polyetheramide resin composition (trade name: HIMAL, manufactured by Hitachi Chemical Co., Ltd.). . Next, the substrate to be processed was immersed in a 22 wt% TMAH aqueous solution maintained at 80 ° C., and the substrate was subjected to anisotropic etching to form an ink supply port 9 (FIG. 2J). At this time, for the purpose of protecting the resin layer on the substrate surface from the etching solution, a protective film (not shown, manufactured by Tokyo Ohka Kogyo Co., Ltd., trade name: OBC) is applied on the ink repellent agent layer to perform anisotropic etching. went.

  Next, after the protective film was dissolved and removed using xylene, the ink flow path pattern 14 was dissolved and removed by immersion while applying ultrasonic waves in methyl lactate, thereby forming the ink flow path 10 (FIG. 2 ( k)).

  The ink jet head produced as described above was observed using an optical microscope and an electron microscope, and the presence / absence of deformation of the ejection port and the positional relationship of the ink flow paths were evaluated. As the evaluation of the positional relationship of the ink flow paths, as shown in FIG. 5, the amount of deviation in the x direction and the y direction from the original ink flow path position was measured. The evaluation results are shown in Table 1.

(Comparative example)
An ink jet head was manufactured according to the process shown in FIG. In the step shown in FIG. 3B, the positive resist layer 3 was formed using polymethyl isopropenyl ketone as the positive resist. Moreover, in the process shown in FIG.3 (c), pattern exposure was performed using the Deep-UV exposure apparatus (The product made from Ushio Electric, brand name: UX-3200). Thereafter, development processing was performed to produce an ink flow path pattern 5 (FIG. 3D). Other conditions were the same as in Example 1. The evaluation results similar to those of Example 1 are also shown in Table 1.

  As described above, by using the ink jet head manufacturing method of the present invention, it is possible to control the positional relationship among the pressure generating element, the ink flow path, and the ejection port with high accuracy and high reproducibility. Further, since the discharge port is not deformed, an ink jet head with good printing characteristics can be manufactured stably.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Pressure generating element 3 Positive resist layer 4 First mask 5 Ink flow path pattern 6 Covering resin layer 7 Second mask (reticle)
8 Ejection port 9 Ink supply port 10 Ink flow path 11 Positive resist layer 12 First reticle (mask)
13 Dyeing pattern 14 Ink flow path pattern 15 Second reticle (mask)

Claims (8)

Forming a positive resist layer formed of a material whose hydrophilicity is expressed or improved by light irradiation on the substrate on which the pressure generating element is formed;
Irradiating the positive resist layer with light to form a light irradiation portion on the surface of the positive resist layer;
A step of selectively coloring at least a surface of a portion serving as an ink flow path in the light irradiation portion of the positive resist layer to form a colored portion in the positive resist layer ;
Patterning the positive resist layer using the colored portion of the positive resist layer as a mask to form an ink flow path pattern; and
Forming a coating resin layer serving as an ink flow path forming member on the substrate on which the ink flow path pattern is formed;
Forming a discharge port in the coating resin layer located above the pressure generating element;
And a step of dissolving and removing the ink flow path pattern to form an ink flow path communicating with the discharge port.   2. The ink jet head manufacturing method according to claim 1, wherein the positive resist layer is colored using a dye solution or a pigment dispersion having a light shielding property with respect to a photosensitive wavelength region of the positive resist layer. Method.   The method of manufacturing an ink jet head according to claim 1, wherein the positive resist layer is formed of a chemically amplified positive photoresist having a photosensitive wavelength region in i-line. The patterning of the positive type resist layer was irradiated with i-rays using a reduced projection exposure apparatus on the positive type resist layer, in any one of claims 1 to 3, characterized in that by performing the development process The manufacturing method of the inkjet head of description. Wherein the step of forming a discharge port in the coating resin layer was irradiated with i-rays using a reduced projection exposure apparatus on the coating resin layer, of claims 1 to 4, characterized in that by performing the development process The manufacturing method of the inkjet head in any one. The inkjet head production according to any one of claims 1 to 5 , wherein a compound including a structure represented by any one of the following general formulas (1) to (3) is used as a material for coloring the positive resist layer. Method.

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each independently represents an unsaturated hydrocarbon group or a substituted or unsubstituted aromatic group. A ₁ represents hydrogen or a halogen element. ] The method of manufacturing an ink jet head according to claim 1, wherein the positive resist layer contains a polymer represented by the following formula (A).

(In formula (A), n and m are integers.) Ink jet head manufactured by the method according to any one of claims 1 to 7.

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