JP2006110910A - Ink jet recording head and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid layer which can be dissolved and removed, which occupies an area which becomes at least a part of an ink flow path provided at a predetermined position of a substrate, made of a discharge port forming material for providing at least a part of a flow path wall and a discharge port. Generation of scum at the opening of the ejection port to the ink flow path when manufacturing an ink jet recording head by a method having a step of forming at least a part of the ink flow path by dissolving the solid layer in a state of being covered with the layer To suppress.
An ultraviolet curable resin composition containing an ultraviolet absorber is used as a discharge port forming material.
[Selection] Figure 7

Description

  The present invention relates to an ink jet recording head for generating ink droplets used in an ink jet recording system and a method for manufacturing the same.

  An ink jet recording head applied to an ink jet recording method generally includes a plurality of fine ink discharge ports (orifices), a liquid flow path (ink flow path), and a plurality of liquid discharge energy generating portions provided in a part of the liquid flow path. Yes. As one method for obtaining a high-quality image with such an ink jet recording head, there is a method in which each of the ink droplets ejected from the ejection port is always ejected from the ejection port at the same volume and ejection speed. As an ink jet recording head for realizing such a method, the distance between the electrothermal transducer and the orifice (hereinafter referred to as “OH distance”) must be set accurately and with good reproducibility. .

  As a method for manufacturing an ink jet recording head capable of setting the OH distance with high accuracy, there is a method described in Japanese Patent Laid-Open No. 6-286149 by the applicant of the present application. In this method, as shown in FIGS. 1 to 6, the distance between the ink discharge pressure generating element and the orifice can be set with a very high accuracy, short and reproducible, and in order to enable high-quality recording, the ink discharge pressure The process of forming the ink flow path pattern with a resin material that can be dissolved on the substrate on which the generating element is formed, and the coating resin containing a solid epoxy resin at room temperature can be dissolved in a solvent, which can be dissolved Forming a coating resin layer to be an ink flow path wall on the dissolvable resin layer by solvent coating on the resin layer, and forming an ink discharge port in the coating resin layer above the ink discharge pressure generating element And a step of eluting a soluble resin layer.

  By irradiating the coating resin layer with ultraviolet rays and performing pattern formation, it is possible to dissolve the discharge port portion even though it is a region that is not irradiated with ultraviolet rays when forming the discharge port at a predetermined portion of the ink flow path wall. It has been confirmed that a slight scum (development residue) is generated at the boundary portion boundary between the flow path pattern layer and the ultraviolet curable coating resin layer that becomes the flow path wall. This scum is an area that is set as an unexposed part for forming an ejection port when light is reflected at the interface between the ink flow path pattern layer and the coating resin layer when the portion to be cured of the coating resin layer is irradiated with ultraviolet rays. This is thought to be because light spilled into a part of the inside and this part was slightly cured. The eaves-like scum projecting in the direction of the inside of the ejection port formed at the opening to the ink channel of the ejection port at the connection between the ink channel and the ejection port is extremely small, and is a characteristic required for an ink jet recording head There is no problem depending on. However, in recent printers, there is a tendency for higher image quality and higher definition, and since the ink discharge amount is reduced, the discharge port size is further miniaturized, so the size of these scums is the same as before. Even when the size is large, there has been a case where the influence on the ejection characteristics, particularly the ink droplet direction, becomes relatively large. Therefore, as a method for solving this problem, Japanese Patent Laid-Open No. 2001-179990 filed by the applicant of the present application discloses a manufacturing method in which a basic substance is added to a solid layer that occupies a portion that becomes an ink flow path. According to this method, the basic substance contained in the solid layer is mixed into the compatible layer made of the solid layer and the discharge port forming material, and the curing reaction by the acid generation catalyst is inhibited. During the removal, the compatible layer is removed, and the generation of scum is eliminated. However, since substances that inhibit the curing reaction of the discharge port forming material are handled, there are cases where curing is difficult to proceed unless care is taken when using basic substances at the production site, so process management is performed reliably. There may be a need. Furthermore, if the progress of the curing reaction changes, there may be variations in the dimensional accuracy of the ejection ports that greatly affect the ejection characteristics between the heads obtained from the ejection port forming materials having different curing reaction rates. In addition, if a sufficiently hardened state cannot be obtained at the portion of the flow path wall made of a cured product of the discharge port forming material, the flow path wall is peeled off from the substrate during long-term use of the head, leading to deterioration of ink discharge performance. In some cases.

Further, in Japanese Patent Application Laid-Open No. 2001-179799 by the applicant of the present application, when the nozzle material is subjected to pattern exposure by including a component that absorbs or scatters ultraviolet rays in the discharge port forming material, A method of manufacturing an ink jet recording head, comprising: forming a latent image having a gradually increasing cross-sectional area of the liquid discharge port; and forming a discharge port having a large cross-sectional area toward the ink discharge energy generation unit. Are listed. In this manufacturing method, the ultraviolet rays reflected at the interface between the discharge port forming material and the solid layer are attenuated in the discharge port forming material, so that the generation of scum is eliminated or very small. An object of the invention described in this publication is to provide a tapered shape in which the cross-sectional area of the ink ejection port gradually increases in order to increase the ejection frequency of the ink droplets. Therefore, in the embodiment of this publication, inorganic pigment particles are added to the discharge port forming material as a component that scatters light, and the layer made of the discharge port forming material is not a homogeneous layer but a non-uniform layer, and is inorganic. The amount of pigment added is as large as 10 to 35%. However, in the structure described in this publication, since the cross section of the discharge port becomes a tapered shape, it is difficult to manage the shape and it may be difficult to produce stably. When the nozzle density is increased for the purpose of discharging the nozzle, there is a limit to further increasing the nozzle density because the discharge port has a swelled shape.
JP-A-6-286149 JP 2001-179990 A JP 2001-179799 A

  The present invention has been made in view of the above-described problems of the prior art, and in a predetermined portion on a substrate, a solid layer that forms at least a part of an ink flow path and a discharge port forming material that covers the solid layer Of the above-described scum generation in a method of forming at least a part of an ink flow path by providing a discharge layer at a predetermined portion of the layer of the discharge port forming material and further dissolving and removing the solid layer It is an object of the present invention to provide an ink jet recording head manufacturing method that can solve the above-mentioned problems and an ink jet recording head obtained thereby. Another object of the present invention is to provide a manufacturing method capable of stably producing an inkjet recording head with high dimensional accuracy. Furthermore, it is also an object of the present invention to provide a method for manufacturing an ink jet recording head using a discharge port forming material having good handleability and an ink jet recording head obtained thereby.

  An ink jet recording head manufacturing method according to the present invention includes an energy generating element that generates energy used to eject ink from an ejection port, and an ink flow that is provided corresponding to the energy generating element and communicates with the ejection port. A step of providing a coating layer of a discharge port forming material that is cured by irradiation of ultraviolet rays so as to cover the solid layer on a substrate provided with a solid layer that forms at least a part of a portion that becomes a path; and the coating Irradiating the layer with ultraviolet rays in a pattern and removing the non-irradiated portion to form the ejection port; and removing the solid layer to form at least a part of the ink flow path. A method for manufacturing an ink jet recording head, wherein the discharge port forming material includes an ultraviolet absorber that does not participate in a curing reaction.

  The ink jet recording head according to the present invention includes an ink that communicates with the ejection port corresponding to the energy generation element on a substrate provided with an energy generation element that generates energy used to eject the ink from the ejection port. In the ink jet recording head provided with the flow path, at least a portion of the wall of the ink flow path including the discharge port is made of a cured product of an ultraviolet curable discharge port forming material containing an ultraviolet absorber that does not participate in the curing reaction. An ink jet recording head is provided.

  According to the present invention, by including the ultraviolet absorbent in the discharge port forming material, even when the discharge port shape is adapted to increase the density of the discharge port, the scum of the opening to the ink flow path is reduced. As a result, it is possible to provide a method capable of accurately manufacturing an ink jet recording head that can cope with a high density of discharge ports.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In this example, an ink jet recording head was prepared according to the procedure shown in FIGS. FIGS. 1 to 6 also illustrate a part of the basic manufacturing method disclosed in Japanese Patent Application Laid-Open No. 6-286149.

  In the conventional example, a substrate 1 made of glass, ceramics, plastic, metal, or the like as shown in a schematic perspective view of FIG. 1 is used. Such a substrate 1 functions as a part of an ink flow path constituent member, and also functions as a support for a discharge port (nozzle) forming material layer that forms an ink flow path and an ink discharge opening (orifice) described later. As long as it is obtained, it can be used without any particular limitation on its shape, material and the like. On the substrate 1, a desired number of energy generating elements 2 for discharging ink such as electrothermal conversion elements or piezoelectric elements are arranged. By such an energy generating element 2, energy for ejecting ink droplets as ink is given to the ink, and recording is performed. For example, when an electrothermal conversion element is used as the energy generating element 2, the element heats nearby ink, thereby causing a change in state of the ink and generating ejection energy. For example, when a piezoelectric element is used, ejection energy is generated by mechanical vibration of the element. These elements 2 are connected to control signal input electrodes (not shown) for operating these elements. In general, various functional layers such as a protective layer are provided for the purpose of improving the durability of the energy generating elements 2, but it is of course possible to provide such a functional layer.

  In FIG. 1, an example in which an opening 3 for supplying ink is provided in advance on the substrate 1 and ink is supplied from the back of the substrate 1 is illustrated. Any method can be used for forming the opening 3 as long as it is a means capable of forming a hole in the substrate 1. For example, it may be formed by mechanical means such as a drill, or light energy such as a laser may be used. Further, a resist pattern or the like may be formed on the substrate 1 and chemically etched. Of course, the ink supply port 3 may not be formed in the substrate 1 but may be formed in a resin pattern and provided on the same surface as the ink discharge port 8 with respect to the substrate 1.

  As will be described later, the ink supply port 3 removes the solid layer after forming an ink flow path pattern (solid layer) and a discharge port forming material layer (coating resin layer), which will be described later, at predetermined positions on the substrate. Prior to the step, it may be formed from the back surface of the substrate by a method such as etching.

  Next, as shown in FIG. 2 (AA ′ cross-sectional view in FIG. 1), an ink flow path pattern 4 (solid layer) is formed on the substrate 1 including the energy generating element 2 with a soluble resin. As the most general means, there is a means of forming with a photosensitive material, but it can also be formed by means of a screen printing method or the like. In the case of using a photosensitive material, the ink flow path pattern can be dissolved, so that it is possible to use a positive resist or a solubility-changing negative resist.

  As a method of forming the solid layer as the ink flow path pattern, when using the substrate 1 provided with the ink supply port 3 on the substrate 1, this photosensitive material is dissolved in an appropriate solvent and PET (polyethylene) is used. It is preferable that a dry film is formed by applying and drying on a film such as terectrate, and then forming by lamination. As the above-mentioned dry film, vinyl ketone photodegradable polymer compounds such as polymethyl isopropyltone and polyvinyl ketone can be suitably used. This is because these compounds maintain characteristics (film properties) as a polymer compound before light irradiation and can be easily laminated on the ink supply port 3. In addition, a filling material that can be removed in a subsequent process is disposed in the ink supply port 3 and a film may be formed by a normal spin coating method, roll coating method, or the like. In this way, on the ink flow path pattern 4 formed of a dissolvable solid layer, as shown in FIG. 3, a coating resin layer 5 which is a discharge port forming material is further applied by a normal spin coating method, roll coating method or the like. Form.

  Here, in the process of forming the resin layer 5, characteristics such as not deforming the soluble resin pattern are required. That is, when the coating resin layer 5 is dissolved in a solvent and formed on the resin pattern 4 that can be dissolved by spin coating, roll coating, or the like, it is necessary to select a solvent so as not to dissolve the soluble resin pattern 4. is there.

  Next, the coating resin layer 5 will be described. As the coating resin layer 5, a photosensitive layer is used because the ink discharge port 3 can be easily and accurately formed by photolithography. Since such a photosensitive coating resin layer 5 forms part of the flow path wall together with the substrate 1, it has high mechanical strength as a structural material, adhesion to the substrate 1, and ink resistance. At the same time, a resolution for patterning a fine pattern of the ink discharge ports is required. In the present invention, an ultraviolet curable resin composition containing an ultraviolet absorber is suitably used as the discharge port forming material. The resin component of this resin composition is preferably a cationically polymerizable epoxy resin, and the resin composition is a photocationic polymerization initiator that causes cationic polymerization upon irradiation with ultraviolet rays, and polymerization by the action of this polymerization initiator. A resin-containing composition is more preferable with an epoxy resin that can be started. The cationic polymerization cured product of an epoxy resin has excellent strength, adhesion, and ink resistance as a structural material, and has excellent patterning characteristics if the epoxy resin is solid at room temperature. That is, a cationic polymerization cured product of an epoxy resin has a high crosslink density (high Tg) as compared with a cured product of an ordinary acid anhydride or amine, and thus exhibits excellent characteristics as a structural material. In addition, by using a solid epoxy resin at room temperature, diffusion of the polymerization initiating species generated from the cationic polymerization initiator by light irradiation into the epoxy resin is suppressed, and excellent patterning accuracy and shape can be obtained. .

  For example, the cationic photopolymerization initiator is 0.1 to 15 parts by weight, preferably 0.3 to 10 parts by weight, more preferably 100 parts by weight of the discharge port forming material (resin composition). Can be used at a ratio of 1 to 8 parts by weight. Furthermore, when an epoxy resin is used as the resin component, the epoxy resin can be used in an amount of 50 to 99 parts by weight, preferably 60 to 98 parts by weight, in 100 parts by weight of the discharge port forming material (resin composition). .

  However, when the pattern is formed by irradiating the area other than the discharge port area of the coating resin layer with ultraviolet rays, the cured resin is used as a boundary with the flow path pattern even though the discharge port portion is not irradiated. It has been confirmed that slight scum (development residue) may be generated. Therefore, in the present invention, the coating resin containing an ultraviolet absorber is used so that the reflected light generated at the interface between the coating resin layer and the nozzle flow path pattern is attenuated and the coating resin layer is not cured in the region where the discharge port is to be formed. The layer is formed as a homogeneous layer.

  This ultraviolet absorber is used to absorb ultraviolet rays and absorb reflected light (ultraviolet rays) generated at the interface between the coating resin layer and the flow path pattern to prevent curing of the resin composition in the discharge port forming region. As in the case of the cationic photopolymerization initiator, it does not have the function of curing the epoxy resin by absorbing ultraviolet rays, and does not cause the coating layer to have light scattering properties that affect the exposure accuracy of the pattern.

  As an example of the ultraviolet absorber which can be added, those which are not basic are preferable, and organic substances (organic compounds) are more preferable. For example, 2,4-di-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4- Benzyloxybenzophenone, 2,2′-hydroxy-4-methoxybenzophenone, phenyl salicylate, 4-t-butylphenyl salicylate, 2-hydroxy-4-methoxybenzophenone, 2,4-di-t-butylphenyl-3 ′, 5'-di-t-butyl-4-hydroxybenzoate can be used, and one kind can be used or a combination of two or more kinds as necessary. Other than this can be used as long as it does not depart from the gist of the present invention.

  The amount of UV absorber added does not hinder the formation of a cured product by UV irradiation at the portion of the flow path wall that needs to be cured, and the reflected light (UV light generated at the interface between the coating resin layer and the flow path pattern). ) To prevent the occurrence of scum, and if necessary, it can be set in consideration of ultraviolet irradiation conditions. This addition amount is, for example, preferably 0.01% by weight to 10% by weight, more preferably 0.03% by weight to 5% by weight, based on the total solid content of the resin composition. By selecting the addition amount from these ranges, it is possible to efficiently improve the scum generation preventing effect while ensuring good adhesion with the substrate of the cured product and good ink resistance as the flow path wall. .

When the addition amount exceeds the upper limit of the above range, the following matters must be considered depending on the structure of the head.
(1) Although the problem of scum generation is eliminated, ultraviolet rays reaching the substrate are attenuated too much, resulting in poor curing on the substrate surface, and may be peeled off from the substrate when the discharge port forming material layer is developed. . (2) Since the ultraviolet absorber is a component that does not contribute to the curing reaction, the discharge port forming material may deviate from its original performance, and in particular, the ink resistance may be reduced and the ink may be peeled off from the substrate surface due to long-term ink immersion. (3) Since the cross-sectional shape of the discharge port is tapered and it is difficult to manage the dimensional accuracy, or the ink inlet of the discharge port becomes too large, the inkjet recording head arranged at high density may be limited in design. is there.

  The solid epoxy resin that can be mainly composed of the resin composition used for the nozzle forming member includes a reaction product of bisphenol A and epichlorohydrin having a molecular weight of about 900 or more, and the reaction of bromosphenol A and epichlorohydrin. Products, phenol novolacs, or reaction products of cresol novolac and epichlorohydrin, for example, JP-A-60-161973, JP-A-63-221121, JP-A-64-9216, JP-A-2-140219 And polyfunctional epoxy resins having an oxycyclohexane skeleton described in the above.

  In the above-described epoxy compound, a compound having an epoxy equivalent of 2000 or less, more preferably 1000 or less, is preferably used. This is because if the epoxy equivalent exceeds 2000, the crosslinking density decreases during the curing reaction, the Tg of the cured product or the heat distortion temperature may decrease, and problems may occur in adhesion and ink resistance. is there.

  As the photocationic polymerization initiator for curing the epoxy resin, a photoacid generator is preferable, and examples thereof include aromatic iodonium salts and aromatic sulfonium salts [J. POLYMER SCI: Symposium, No. 56, 383-395 (1976)] and commercial products SP-150, SP-170, SP-172 and the like marketed by Asahi Denka Kogyo Co., Ltd. are listed.

  Moreover, the above-mentioned photocationic polymerization initiator can accelerate | stimulate cationic polymerization (a crosslinking density improves compared with single photocationic polymerization) by using a reducing agent together and heating. However, when a photocationic polymerization initiator and a reducing agent are used in combination, the reducing agent is selected so that it becomes a so-called redox type initiator system that does not react at room temperature and reacts at a certain temperature or higher (preferably 60 ° C. or higher). There is a need.

  As such a reducing agent, copper triflate (copper trifluoromethanesulfonate (II)) is most suitable in consideration of the copper compound, particularly reactivity and solubility in the epoxy resin. A reducing agent such as ascorbic acid is also useful.

  In addition, when a higher crosslinking density (high Tg) is required, such as an increase in the number of nozzles (high-speed printability) or use of non-neutral ink (improvement of water resistance of the colorant), the above-mentioned reducing agent is described later As described above, the crosslinking density can be increased by a post-process in which the coating resin layer is dipped and heated using the solution after the development process of the coating resin layer.

  Furthermore, a silane coupling agent is added to the above composition as necessary to add a flexibility-imparting agent for the purpose of lowering the elastic modulus of the epoxy resin, or to obtain further adhesion to the substrate 1. Can be added.

  In addition, the coating resin layer obtained using the resin composition used as the discharge port forming material in the present invention is formed as a homogeneous layer. The homogeneous layer is such that the composition of the resin composition constituting the homogeneous layer is uniform to the extent that the desired light transmittance can be obtained over the entire layer. For example, when an inorganic pigment having a large particle size is dispersed in a layer, light scattering occurs and the desired light transmittance cannot be obtained.

  Next, the photosensitive coating resin layer 5 made of the above compound is subjected to pattern exposure through a mask 6 as shown in “pattern exposure diagram of ink discharge port” in FIG. The photosensitive coating resin layer 5 is a negative type and shields a portion where an ink discharge port is formed with a mask (of course, also shields a portion where electrical connection is made, not shown). The pattern exposure can be appropriately selected from ultraviolet rays, deep-UV light, electron beams, X-rays and the like according to the photosensitive region of the photocationic polymerization initiator to be used. Here, all of the steps so far can be aligned using conventional photolithography technology, and the accuracy can be significantly improved as compared with a method in which an orifice plate is separately prepared and bonded to a substrate. The photosensitive coating resin layer 5 that has been subjected to pattern exposure in this manner may be subjected to heat treatment in order to accelerate the reaction as necessary. Here, as described above, since the photosensitive coating resin layer 5 is composed of an epoxy resin that is solid at room temperature, diffusion of the cationic polymerization initiating species does not occur in pattern exposure, and has excellent patterning accuracy. The shape can be realized.

  Next, the pattern-exposed photosensitive coating resin layer 5 is developed using an appropriate solvent to form an ink discharge port 8 as shown in FIG. Here, it is also possible to develop the dissolvable resin pattern 4 that forms the ink flow path simultaneously with the development of the unexposed photosensitive coating resin layer. However, in general, a plurality of recording heads having the same or different forms are arranged on the substrate 1 and used as an ink jet recording head through a cutting process. Therefore, as a countermeasure against dust at the time of cutting, as shown in FIG. By selectively developing only the photosensitive coating resin layer 5, the resin pattern 4 forming the ink flow path is left (the resin pattern 4 remains in the liquid chamber, so that dust generated during cutting does not enter) and is cut. It is also possible to develop the resin pattern 4 after the process (FIG. 6 diagram after elution of the flow path pattern). At this time, since the scum (development residue) generated when developing the photosensitive coating resin layer 5 is eluted together with the dissolvable flow path pattern 4, almost no residue remains in the nozzle.

  As described above, the opening 3 provided in the substrate 1 can be formed by using a substrate without such an opening and using a method such as etching before the flow path pattern 4 is eluted. . When wet etching is used for this etching, for example, a process using anisotropic etching described in Japanese Patent Application Laid-Open No. 2004-262241 can be used. For example, an etching resistant film such as a polyether amide film is formed on the back surface of the substrate in a predetermined pattern, and the surface of the discharge port forming material layer is protected with a layer of a protective material such as cyclized rubber. In this case, the opening 3 can be produced by performing anisotropic etching using a mixed solution of hydrofluoric acid and ammonium fluoride as an etchant.

  Electrical connection (not shown) for driving the ink supply member 7 and the energy generating element 2 is performed on the substrate 1 formed with the ink flow path and the ink discharge port thus formed. An ink jet recording head is formed (FIG. 7 is a substrate diagram in which an ink supply unit is arranged). In the configuration of FIG. 7, ink is supplied to the ink supply port 3 through an ink passage (not shown) from an ink tank (not shown) in which ink is stored. The ink fills the ink flow path on the electrothermal conversion element 2 on the substrate 1, and a meniscus is formed at the ink discharge port 8 due to the surface tension of the ink. When ink is ejected from the ink ejection port 8, electric power is supplied from a power supply line (not shown), the electrothermal conversion element 2 generates heat, and ink is ejected by pressure generated by foaming of volatile components in the ink.

  The ink jet recording head manufacturing method according to the present invention is effective as a full-line type recording head capable of recording simultaneously over the entire width of the recording paper, and also for a color recording head in which recording heads are integrated or combined. is there.

Although the above has mainly described the basic aspects to which the present invention can be applied, the embodiments of the present invention will be described in detail.
Example 1
First, in FIG. 1, a blast mask is placed on a silicon substrate 1 on which an electrothermal conversion element 2 (heater made of material HfB2) as an energy generating element for ink discharge is formed, and ink supply is performed by sandblasting. A through-hole 3 was formed. Next, a polymethylisopropenyl ketone (trade name ODUR-1010 manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied onto the substrate 1 as a soluble resin layer 4 and dried to form a dry film. It transferred to the substrate 1 by lamination. ODUR-1010 was concentrated and used because it has a low viscosity and cannot form a thick film. Next, each of the above was pre-baked at 120 ° C. for 20 minutes, and then pattern exposure of the ink flow path 4 was performed using a mask aligner PLA520 (trade name Cold Mirror CM290) manufactured by Canon Inc. Exposure was 1.5 minutes, development was methyl isobutyl ketone / xylene = 2/1, and rinsing was xylene. The pattern 4 formed of this dissolvable resin is for securing an ink flow path between the ink supply port 3 and the electrothermal conversion element 2 (FIG. 2). The resist film thickness after development was 10 μm. Next, the following resin composition 1 was dissolved in a methyl isobutyl ketone / xylene mixed solvent at a concentration of 50 wt%, and a photosensitive coating resin layer 5 was formed by spin coating (film thickness on the flow path pattern 4 is 10 μm, FIG. 3). ). Here, KEMISORB 11 is an ultraviolet absorber.

(Resin composition 1)
Epoxy resin: EHPE-3158 (manufactured by Daicel Chemical Industries): 100 parts by weight Silane coupling agent: A-187 (manufactured by Nihon Unicar): 5 parts by weight Photoacid generator: SP-170 (Asahi Denka Kogyo) (Manufactured by Co., Ltd.): 1.5 parts by weight UV absorber: KEMISORB 11 (manufactured by Chemipro Kasei Co., Ltd.): 0.3 parts by weight Next, for forming the ink discharge port 8 with the mask aligner PLA520 (CM250). The pattern exposure was performed (FIG. 4). The exposure was performed for 15 seconds, and the after baking was performed at 60 ° C. for 30 minutes. Next, development was performed with methyl isobutyl ketone to form ink discharge ports. In this example, a discharge port pattern of φ10 μm was formed. Next, in order to enhance the removability of the dissolvable resin layer 4 (polymethylisopropenyl ketone), after exposing again with the PLA520 (CM290) for 2 minutes, it is immersed while applying ultrasonic waves in methyl lactate. The remaining ink flow path pattern 4 was eluted (FIG. 6). Next, the ink jet recording head was heated at 180 ° C. for 1 hour to completely cure the photosensitive coating material layer 5. Finally, as shown in FIG. 7, the ink supply member 7 was adhered to the ink supply port 3 to complete the ink jet recording head of the embodiment of the present invention.

(Example 2)
An ink jet recording head was prepared in the same manner as in Example 1 except that the following resin composition 2 was used for the coating resin layer. (The film thickness on the flow path pattern 4 is 10 μm, FIG. 3).
Here, KEMISORB 12 is an ultraviolet absorber.
(Resin composition 2)
EHPE-3158 (manufactured by Daicel Chemical Industries): 100 parts by weight A-187 (manufactured by Nihon Unicar): 5 parts by weight SP-170 (manufactured by Asahi Denka Kogyo Co., Ltd.): 1.5 parts by weight KEMISORB 12 (Kemipro Kasei Co., Ltd.): 0.5 part by weight (Comparative Example 1)
As Comparative Example 1, an ink jet recording head was prepared in the same manner as in Example 1 except that the following resin composition was used as the coating resin layer. A resin composition containing no ultraviolet absorber was used for this resin composition.
(Comparative example / resin composition)
EHPE-3158 (manufactured by Daicel Chemical Industries, Ltd.): 100 parts by weight A-187 (manufactured by Nippon Unicar Co., Ltd.): 5 parts by weight SP-170 (manufactured by Asahi Denka Kogyo Co., Ltd.): 1.5 parts by weight The ink jet recording heads of Examples 1 and 2 and Comparative Example 1 prepared as described above were mounted on a recording apparatus, and pure water / diethylene glycol / isopropyl alcohol / lithium acetate / black dye hood black 2 = 79.4 / 15/3/0. When recording was performed using an ink composed of .1 / 2.5, stable printing was possible in all of the examples, and the obtained printed matter was of high quality. However, in the comparative conventional example, disorder of printing was recognized. When each head was disassembled and observed, a scum of about several nanometers was observed in a part of the ink flow path at the entrance of the ink discharge port in the conventional example. No scum was observed in the head of this example.

  As described above, according to the embodiment of the present invention, the energy generating element 2, the solid layer 5 that occupies at least the portion that becomes the flow path, and the ultraviolet curable nozzle forming member 5 on the substrate 1 provided. In an ink jet recording head manufacturing method including a step of forming a discharge port 8 by exposure and development, and forming an ink flow path by removing the solid layer 5, a UV absorber is uniformly applied to the discharge port forming material. By adding to the scum, the scum generated in a part of the ink flow path can be suppressed to a very small level or not at all. For this reason, even in an ink jet recording head that ejects minute ink droplets, the disorder of ejection does not become a problem.

It is typical sectional drawing which shows the basic manufacturing process of an inkjet recording head. It is a typical perspective view of the board | substrate for demonstrating the manufacturing process of an inkjet recording head. It is typical sectional drawing for demonstrating the manufacturing process of an inkjet recording head. It is typical sectional drawing for demonstrating the manufacturing process of an inkjet recording head. It is typical sectional drawing for demonstrating the manufacturing process of an inkjet recording head. It is typical sectional drawing for demonstrating the manufacturing process of an inkjet recording head. It is typical sectional drawing for demonstrating the manufacturing process of an inkjet recording head.

Explanation of symbols

1 Substrate 2 Electrothermal conversion element (energy generating element for ink ejection)
3 Ink Supply Port 4 Ink Flow Pattern 5 Photosensitive Coating Resin Layer 6 Negative Mask 7 Ink Supply Member 8 Ink Ejection Port

Claims (9)

An energy generating element that generates energy used to discharge ink from the discharge port, and at least a part of a portion that is provided corresponding to the energy generation element and serves as an ink flow path that communicates with the discharge port are formed. A step of providing a coating layer of a discharge port forming material that is cured by irradiation of ultraviolet rays so as to cover the solid layer on a substrate provided with a solid layer;
Irradiating the coating layer with ultraviolet rays in a pattern, and forming the discharge port by removing an unirradiated portion;
Forming at least a portion of the ink flow path by removing the solid layer;
Have
The method for manufacturing an ink jet recording head, wherein the discharge port forming material contains an ultraviolet absorber that does not participate in a curing reaction.   The method of manufacturing an ink jet recording head according to claim 1, wherein the ejection port is provided on a flow path wall that partitions the ink flow path from the outside.   3. The method of manufacturing an ink jet recording head according to claim 1, wherein the discharge port forming material includes a cationic photopolymerization initiator and a cationic polymerizable epoxy resin, and the ultraviolet absorber is not basic.   The inkjet recording head according to any one of claims 1 to 3, wherein a ratio of the ultraviolet absorber added to the discharge port forming material is 0.01 to 10% by weight based on the total solid content of the discharge port forming material. Manufacturing method.   The method of manufacturing an ink jet recording head according to claim 1, wherein the ultraviolet absorber is an organic substance.   An ink jet recording head manufactured by the manufacturing method according to claim 1. An ink jet in which an ink flow path communicating with the discharge port corresponding to the energy generation element is provided on a substrate provided with an energy generation element that generates energy used to discharge ink from the discharge port. In the recording head,
An ink jet recording head, wherein at least a portion of the wall of the ink flow path including the discharge port is made of a cured product of an ultraviolet curable discharge port forming material including an ultraviolet absorber that does not participate in a curing reaction.   The ink jet recording head according to claim 7, wherein the ejection port is provided in a flow path wall that partitions the ink flow path from the outside. The ink jet recording head according to claim 7 or 8, wherein the ultraviolet absorber is an organic substance.

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