Inkjet recording head manufacturing method

Abstract

To provide an inkjet recording head which is sealed with a sealing material having sealing property, moldability and productivity.SOLUTION: An inkjet recording head has a substrate having a discharge port for discharging a liquid, and a member provided with a recess for storing the substrate, and has a sealing material for sealing a gap formed between a wall of the recess of the member and the substrate, wherein the sealing material includes at least a cured product of a composition containing a hydrogenated bisphenol A type epoxy resin, a solid basic compound and polythiol.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an inkjet print head in which components constituting the inkjet print head are sealed with a sealant. [Background technology]

[0002] An inkjet print head is a device that has a plurality of energy generating elements and ejects liquid from a plurality of ejection ports using energy provided by the energy generating elements. An example of an inkjet print head is an inkjet print head installed in an inkjet printing apparatus that performs printing by ejecting ink onto a recording paper. An inkjet print head is composed of various components, such as a substrate having ejection ports for ejecting ink, electrical wiring for electrically controlling the ejection, etc. After assembling the various components of an inkjet print head, the gaps between the components are filled with a sealant to prevent ink from penetrating into the gaps. As such a sealing material, Patent Document 1 describes a sealing material containing a urethane resin obtained by reacting a polyol compound with an isocyanate compound. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 2904629 Summary of the Invention [Problem to be solved by the invention]

[0004] The sealant used in inkjet print heads is required to have various properties, such as insulation when sealing electrical wiring, ink resistance in areas where ink will adhere, and wipe resistance when cleaning. Furthermore, the shapes of inkjet recording heads have changed in recent years, and sealing properties that match the shape and material of the adherend are required. Therefore, low viscosity and flatness are also required to ensure even flow between thin components. Furthermore, in structures where the adherend is long and thin, such as long heads, there is a concern that the adherend may deform due to the difference in linear expansion coefficient between the adherend and the sealing material. Therefore, low-temperature curing properties that prevent deformation of the components are also required. On the other hand, in terms of productivity, materials that can reduce equipment maintenance time are required. In the case of two-component mixing dispensers, the mixing part is used repeatedly, so the cleaning process takes time, which reduces productivity. Also, from the perspective of taktivity and stability when the material is used, it is desirable for the encapsulant to have a long pot life. Also, from the perspective of stability when the material is used and productivity, it is desirable for the encapsulant to have a long pot life and to harden in a short time.

[0005] There is a possibility that the urethane resin obtained by reacting a general polyol compound with an isocyanate compound as described in Patent Document 1 may not be able to fully satisfy these requirements. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an ink jet recording head sealed with a sealing material that is excellent in sealing properties, moldability and productivity. [Means for solving the problem]

[0006] The present invention provides an ink jet recording head having a substrate having an ejection port for ejecting a liquid, and a member having a recess for accommodating the substrate, a gap formed between a wall of the recess of the member and the substrate, and a sealant that seals the gap; The inkjet recording head is characterized in that the sealing material contains a cured product of a composition containing at least a hydrogenated bisphenol A type epoxy resin, a solid basic compound, and a polythiol. The present invention also provides a suitable method for producing a sealant used in the ink jet recording head, as described below. A method for producing an encapsulant, comprising the steps of: kneading a hydrogenated bisphenol A epoxy resin with a solid basic compound to produce mixture 1; and kneading the mixture 1 with a polythiol to produce mixture 2. a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A epoxy resin and a silica filler to produce a mixture 3; a step of kneading the mixture 1, the mixture 3, and a polythiol to produce a mixture 4; A method for producing an encapsulating material, comprising: a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A type epoxy resin, a silica filler, and a polythiol to produce a mixture 5; A method for producing an encapsulant, comprising a step of kneading the mixture 1 and the mixture 5 to produce a mixture 6. The present invention also provides a method for manufacturing an ink jet recording head, characterized in that the sealing material manufactured by the above manufacturing method is used. [Effects of the Invention]

[0007] According to the present invention, there is provided an ink jet recording head sealed with a sealing material that has sealing properties, moldability and productivity. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing one embodiment of an ink jet recording head. [Figure 2] 2(a) is a partially enlarged view of the ink jet recording head, and FIG. 2(b) is a cross-sectional view taken along line AA' shown in FIG. 2(a). [Figure 3] 1 shows the change in viscosity over time in Examples 15 and 17. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail. <Inkjet recording head> First, the configuration of the inkjet recording head of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view of one embodiment of the inkjet recording head of the present invention. Fig. 2(a) is a partially enlarged view of the inkjet recording head, and Fig. 2(b) is a cross-sectional view of the inkjet recording head taken along line AA' shown in Fig. 2(a). The inkjet recording head 1 has a substrate 2 and a member 3 that supports the substrate 2. The substrate 2 has ejection ports 4 for ejecting ink, energy generating elements (not shown) that generate energy for ejecting the ink, and electronic circuit elements (not shown) that control the energy generating elements.

[0010] The inkjet recording head 1 is a so-called line-type head capable of high-speed printing. A line-type head is an inkjet recording head that has a width equal to or greater than the width of recording paper and has multiple substrates 2 arranged in-line along the width direction. The multiple substrates 2 are arranged continuously on the inkjet recording head 1 over a length equal to or greater than the width of the recording paper so that, with the inkjet recording head fixed, recording can be performed on the entire area of ​​the recording paper in the width direction by passing the recording paper just once. Note that the width of the recording paper here is assumed to be the width of the short side of A4 paper. A plurality of substrates 2 arranged in line are housed in recesses 3b provided in a member 3. When the inkjet recording head 1 is viewed from the side where the ejection ports are open, gaps are formed between the substrates 2 and the side walls 3a of the recesses 3b of the member 3. There may also be gaps between the substrates 2 themselves. These gaps are sealed with a sealant 5. The sealant 5 is formed by pouring a sealant composition into the gaps between the substrates 2 and the side walls 3a of the recesses 3b of the member 3 and curing it.

[0011] <Sealing composition> Next, the composition for the encapsulant will be described below: The epoxy resin composition for the encapsulant used in the present invention contains at least a hydrogenated bisphenol A type epoxy resin, a solid basic compound, and a polythiol. The composition has suitable sealing properties, moldability and productivity so that it can be used as a desired sealing material. First, the performance of the composition will be described. ·Sealability Sealant materials used in inkjet recording heads are required to be ink-resistant against ink contact and wipe-resistant for cleaning. The sealant used in the present invention cures through thiol curing (anionic polymerization reaction) caused by the polythiol contained in the composition, and functional groups that contribute to adhesion, such as hydroxyl groups, remain even after curing. In addition, the -S- derived from the thiol is flexible, and strong adhesion to the substrate can be expected even in harsh environments. This makes it possible to prevent the penetration of ink that seeps through the interface between the substrate and the sealant. Furthermore, the use of epoxy resin provides excellent mechanical strength and ensures wipe-resistant properties. ·Moldability As shown in Figure 2, between multiple substrates 2 arranged in-line, the sealant must be poured into recesses 3b with a narrow width of several tens of micrometers to several millimeters. Therefore, the sealant preferably has low viscosity. The viscosity of the sealant is preferably 40 Pa·s or less. Furthermore, the sealant desirably has low elasticity so as not to generate stress in the head member due to temperature rise during the inkjet recording head mounting process or during printing by a printer. From this perspective, the modulus of elasticity of the sealant is preferably 20 GPa or less, and more preferably 10 GPa or less. The sealant used in the present invention uses hydrogenated bisphenol A epoxy resin as the epoxy resin from the viewpoints of low viscosity and low elasticity. Furthermore, in cases where the area to be sealed with the sealant is large, thermal curing at high temperatures may cause deformation of the adherend or damage to the components due to the difference in linear expansion between the adherend and the sealant. Therefore, a composition that can be cured at room temperature or at a low temperature of 100°C or less is effective. Since the reaction rate of anionic polymerization of epoxy resins is generally slow, the sealant of the present invention increases its reactivity by adding polythiol as a curing agent. Productivity Storage stability is required for productivity. A pot life of 8 hours or more at room temperature is desirable, but one-component encapsulants generally have a shorter pot life than two-component encapsulants. This encapsulant contains a hydrogenated bisphenol A epoxy resin, a solid basic compound, and a polythiol, which provides sufficient pot life. To delay the curing reaction and achieve a longer pot life, a preferred method is to first mix the hydrogenated bisphenol A epoxy resin and the solid basic compound, and then mix the resulting mixture with the polythiol, as described below. This is because mixing the epoxy resin and the solid basic compound first coats the solid basic compound with the epoxy resin. This allows for a longer time for the solid basic compound to dissolve in the polythiol. This delays the time until the reaction between the epoxy resin and the polythiol begins. Therefore, even at room temperature, the viscosity of the one-component encapsulant increases slowly, providing a sufficient pot life. The pot life is defined as the time at room temperature during which the viscosity immediately after mixing is doubled.

[0012] Next, each of the components of the composition for the encapsulant will be described. (epoxy resin) The epoxy resin is the main component (the curing component most abundant in the composition), and hydrogenated bisphenol A epoxy resin is used. Hydrogenated bisphenol A epoxy resins have the characteristics of low elasticity, being free of double bonds and aromatic rings, and having a narrow molecular weight distribution. From the viewpoint of low viscosity, hydrogenated bisphenol A epoxy resins are preferably high-purity resins, and post-hydrogenated bisphenol A epoxy resins formed by post-hydrogenation are more preferred. Furthermore, from the viewpoint of storage stability, the epoxy resin is preferably an alicyclic epoxy resin. This is because alicyclic epoxy resins have reduced reactivity in anionic polymerization systems, which is effective in extending the usable time. Furthermore, as mentioned above, in order to cover a solid basic compound with a hydrogenated bisphenol A epoxy resin, it is effective for the epoxy resin to be liquid. When using an epoxy resin that is solid at room temperature, it is recommended to heat it to a temperature at which the solid basic compound does not melt, or to dissolve it in another liquid epoxy resin. Specific examples of the epoxy resin include jER YX8000, YX8000D, YX8034, and YX8040, which are hydrogenated epoxy resins manufactured by Mitsubishi Chemical Corporation. The hydrogenated bisphenol A epoxy resin may be one type or two or more types.

[0013] (Polythiol) The polythiol functions as a curing agent. There are no particular limitations on the polythiol, but a polythiol with high reactivity and a relatively low molecular weight is usually selected. As such a polythiol, one that is liquid at room temperature can be suitably used. Examples include pentaerythritol trispropanethiol (PEPT), trimethylolpropane tris(3-mercaptopropionate) (TMMP), pentaerythritol tetrakis(3-mercaptopropionate), and p-xylene dithiol. Commercially available products include PEPT (manufactured by SC Organic Chemicals), TMMP (manufactured by SC Organic Chemicals), Cupcure 3-800 (trade name, manufactured by Mitsubishi Chemical Corporation), and QX11 (trade name, manufactured by Mitsubishi Chemical Corporation). When the sealing material of the present invention is used in a location requiring higher chemical resistance, a polythiol having an ether skeleton, which has higher chemical resistance, is preferred, particularly an ether-type polyfunctional thiol. A polythiol having an ether skeleton refers to a compound having two or more thiol groups in the side chain, not containing a hydrolyzable ester bond in the main chain, and having an ether bond that has excellent properties such as chemical resistance due to its high bonding strength. Furthermore, a polythiol having an ether skeleton is also effective in reducing viscosity. The polythiol content is preferably such that the thiol equivalent of the polythiol is 0.5 to 1 equivalent per 1 epoxy equivalent of the hydrogenated bisphenol A epoxy resin. When the polythiol equivalent is 0.5 or more equivalents relative to the epoxy resin, the reaction between the epoxy resin and the polythiol occurs sufficiently quickly, enabling curing in a short period of time. Furthermore, when the polythiol equivalent is 0.5 or more equivalents, the polymerization reaction between the epoxy resin and the polythiol proceeds as the main reaction, and the polymerization reaction between the epoxy resin and the base derived from the solid basic compound as a side reaction is less likely to occur. As a result, the thioether structure (-S-) derived from the polythiol, which is necessary for achieving flexibility, is sufficiently formed, which is preferable from the standpoint of adhesiveness. When the polythiol equivalent is 1 or less relative to the epoxy resin, the amount of unreacted polythiol that cannot react with the epoxy resin is reduced. This suppresses deterioration of mechanical properties, such as a decrease in adhesive strength, due to unreacted polythiol. Furthermore, even when a sealant is used in a portion that comes into contact with ink, the production of unreacted polythiol is suppressed, so that the unreacted polythiol does not elute into the ink, which is preferable because it prevents the sealant from swelling with the ink.

[0014] (Solid basic compounds) The solid basic compound functions as a curing catalyst. There are no particular limitations on the solid basic compound as long as it is solid at room temperature, but it is preferable to use one that is difficult to dissolve in epoxy resins. Examples include dicyandiamide, which is commonly used as a latent curing agent, dihydrazide compounds, solid aromatic amines such as diaminodiphenylmethane (DDM) and diaminodiphenylsulfone (DDS), various imidazoles, and various amine adduct latent curing agents. Amine adduct latent curing agents are particularly suitable for curing epoxy resins. The preferred range of the content of the solid basic compound varies depending on the conditions of use. For example, under conditions requiring a long pot life, the content of the solid basic compound is preferably 1.5 to 2.5 parts by mass per 100 parts by mass of hydrogenated bisphenol A epoxy resin. When the content of the solid basic compound is 1.5 parts by mass or more relative to the epoxy resin, curing can be achieved in a short period of time. When the content of the solid basic compound is 2.5 parts by mass or less relative to the epoxy resin, the solid basic compound is sufficiently coated with the epoxy resin, reducing the amount of solid basic compound that dissolves into the polythiol and ensuring a sufficient usable time. Furthermore, when the conditions of use require rapid curing at low temperatures such as room temperature, the content of the solid basic compound is preferably 2.5 to 10 parts by mass per 100 parts by mass of hydrogenated bisphenol A epoxy resin. When the content of the solid basic compound is 2.5 parts by mass or more relative to the epoxy resin, sufficient curing can be expected to be promoted, and when the content of the solid basic compound is 10 parts by mass or less relative to the epoxy resin, it is an appropriate amount as a non-curing component.

[0015] (Silane agent (silane coupling agent)) A silane agent may be further added to the sealing material according to the present invention. To lower the viscosity, it is preferable to add a low-molecular-weight silane agent. The silane agent to be added has a molecular weight of 500 or less, preferably 300 or less. Furthermore, a compound having an alicyclic epoxy skeleton, which is characterized by low viscosity, is effective as the silane agent to be added. Preferred modifying groups of the silane agent include an epoxy group, a mercapto group, an isocyanate group, and a fluorene skeleton. However, basic silane coupling agents such as amine compounds act as catalysts, immediately initiating a reaction and shortening the usable time, so their use is not appropriate. When the sealant of the present invention is used in a situation where stronger adhesion is required at the interface between the adherend and the sealant, the silane agent preferably has an epoxy group or a mercapto group. In the sealant of the present invention, since the main agent is an epoxy resin and the curing agent is a polythiol, it is thought that it has good compatibility with these silane coupling agents and peeling at the interface between the adherend and the sealant is less likely to occur. The preferred range of the content of the silane agent varies depending on the conditions of use. For example, under conditions requiring curability and adhesion, the content of the silane agent is preferably 1 to 50 parts by mass relative to 100 parts by mass of hydrogenated bisphenol A epoxy resin. When the content of the silane agent relative to the epoxy resin is 1 part by mass or more, adhesion to inorganic members can be improved, and when it is 50 parts by mass or less, unreacted components of the silane agent can be prevented from remaining. Furthermore, under conditions requiring swelling resistance, pot life, and low viscosity, the content of the silane agent is preferably 50 to 75 parts by mass per 100 parts by mass of hydrogenated bisphenol A epoxy resin. Compounds containing inorganic components that are resistant to swelling, such as silane agents and silica fillers described below, can be expected to improve swelling resistance depending on the amount added. Furthermore, since silane agents have fewer reactive groups per molecule than epoxy resins, they can also be expected to have the effect of extending pot life. However, because reactivity tends to be low, it is preferable to adjust the amount of thiol curing agent added to achieve both pot life and curability. The order of mixing the silane coupling agents is not particularly limited, but it is preferable to mix the epoxy group-containing silane coupling agent and the mercapto group-containing silane coupling agent at the same time as mixing the main epoxy resin and the polythiol.

[0016] (Other additives) A diluent or other additives may be optionally added to the sealing composition containing the above components. For example, silica filler can be added as needed. The addition of silica filler can impart the inherent properties of silica filler, such as swelling resistance and storage stability. The addition of silica filler also reduces the linear expansion coefficient and deformation of the adherend. While general-purpose silica fillers can be used, to suppress viscosity increases, microsilica fillers (particle diameter: approximately 10 μm to 100 nm) or macrosilica fillers (particle diameter: approximately 100 μm to 10 μm) with a particle size of 0.1 μm or more are preferred. The particle size refers to the volume cumulative particle size D50 measured using a laser diffraction / scattering particle size analyzer. Furthermore, for the purpose of increasing the affinity with other materials, silane-treated silica fillers are also suitable. The content of the silica filler is preferably 100 to 800 parts by mass relative to 100 parts by mass of the hydrogenated bisphenol A epoxy resin. When the content of the silica filler relative to the epoxy resin is 100 parts by mass or more, swelling can be suppressed, and when the content of the silica filler relative to the epoxy resin is 800 parts by mass or less, viscosity can be suppressed to a level that allows application. Furthermore, in order to apply the sealant with high precision, a pigment may be added to detect the amount of sealant applied. A dispersant may be added to the pigment to disperse it well.

[0017] Next, a method for producing the encapsulant composition will be described. (Method of manufacturing encapsulant composition) In the method for producing a sealing material according to the present invention, the raw materials for the sealing material are mixed in the following order for the purpose of suppressing dissolution of the solid basic compound in the polythiol. (Sealant without silica filler) In the method for producing a sealing material according to this embodiment, a sealing material that does not contain a silica filler is produced. The production of a sealing material that does not contain a silica filler can be carried out in the following order of steps. a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; and kneading the mixture 1 with a polythiol to produce a mixture 2. In this production method, it is particularly preferable to produce mixture 2 by kneading mixture 1 and polythiol within one hour after the production of mixture 1. According to this production method, the viscosity did not increase as much even when stored at room temperature, and the product had a sufficient usable life, compared to when the components were kneaded all at once without following the above-mentioned order. In particular, by kneading the polythiol within one hour after the production of the mixture 1, a rapid increase in viscosity can be suppressed, and the usable time can be extended.

[0018] (Sealing material containing silica filler) In the method for producing a sealing material according to this embodiment, a sealing material containing a silica filler is produced. There are two embodiments for producing the sealing material containing the silica filler. The first embodiment can be carried out in the following order of steps. a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A epoxy resin and a silica filler to produce a first mixture (3); a step of kneading the mixture 1, the mixture 3, and a polythiol to produce a mixture 4; It has. In this production method, it is particularly preferable to knead the mixture 1, the mixture 3, and the polythiol within one hour after the production of the mixture 1 to produce the mixture 4. According to this production method, the sealing material kneaded in this order had a longer usable life. In particular, by kneading the polythiol within one hour after the production of the mixture 1, a rapid increase in viscosity can be suppressed, and the usable time can be extended.

[0019] The second embodiment can be implemented in the following order of steps. a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A type epoxy resin, a silica filler, and a polythiol to produce a mixture 5; The method further comprises a step of kneading the mixture 1 and the mixture 5 to produce a mixture 6. In this production method, it is preferable that within one hour after the production of the mixture 1, the hydrogenated bisphenol A type epoxy resin, the silica filler, and the polythiol are kneaded to produce the mixture 5, and the mixture 1 and the mixture 5 are kneaded to produce the mixture 6. According to this production method, the silica filler increases the viscosity of the mixture 5, further suppressing contact between the solid basic compound coated with the hydrogenated bisphenol A epoxy resin and the polythiol. A silane agent may also be added to the mixture 5. The amount of epoxy resin used in the mixture can be adjusted as needed, as long as the respective components are mixed together. In particular, by kneading the polythiol within one hour after the production of the mixture 1, a rapid increase in viscosity can be suppressed, and the usable time can be extended. [Example]

[0020] The following examples will further illustrate the embodiments of the present invention. Examples 1 to 14 and Comparative Examples 1 to 2 <Preparation of Composition for Sealant> Table 1 shows the materials used in the examples and comparative examples, the composition ratios of the materials, and the evaluation results. In Examples 1 to 10 and 13 to 14, a hydrogenated bisphenol A epoxy resin as the main component and a solid basic compound as the catalyst were kneaded together to form mixture A. After 12 hours, mixture B, which was a mixture of the same epoxy resin and silica filler, and a polythiol curing agent and a silane agent were added and kneaded together (mixture A + B + curing agent + silane agent). In Example 11, the epoxy resin as the main component and the solid basic compound as the catalyst were kneaded to form mixture A, and after 12 hours, mixture A was kneaded with polythiol, silica filler, and silane agent to form mixture C. In Example 12 and Comparative Examples 1 and 2, all materials were kneaded simultaneously. The epoxy resin as the main component and the thixotropic agent were mixed in a HIVIS MIX model 3 manufactured by Primix Corporation at 1000 rpm for 2 minutes in a vacuum, and all components other than the epoxy resin and the thixotropic agent were mixed at 600 rpm for 5 minutes in a vacuum.

[0021] <Evaluation method for encapsulants> The following six types of evaluations were carried out on the sealing materials formed using the compositions of Examples 1 to 14 and Comparative Examples 1 and 2. The evaluation results are shown in Table 1. Insulation The compositions of Examples 1 to 14 and Comparative Examples 1 and 2 were placed in a mold and left to cure at room temperature for at least one day. The resulting cured product was removed from the mold to serve as an evaluation sample for the encapsulant. The volume resistivity of the evaluation sample was measured. The volume resistivity was determined according to the ISO 2951 test method, using an applied voltage of 500 V. Ink resistance The evaluation sample was immersed in ink (water:organic solvent:surfactant=75:25:1) in a mass ratio 20 times that of the evaluation sample and heated at 105°C for 10 hours. Note that this ink does not contain colorant because it is for evaluation purposes. The mass of the evaluation sample before and after heating was measured, and the ink absorption rate was calculated based on the mass of the evaluation sample before heating. ·Durability The compositions of Examples 1 to 14 and Comparative Examples 1 and 2 were poured into the sealant 5 of the inkjet recording head 1 shown in FIG. 1 using a dispenser, taking care not to introduce bubbles. The compositions were then left to harden for at least one day. The resulting inkjet recording head was subjected to a durability test in which it was rubbed 1,000 times with a blade (made of acrylonitrile butadiene rubber), and the presence or absence of scratches or abrasions on the surface of the sealant after the durability test was examined using an optical microscope. Elastic modulus Using the above evaluation samples, the elastic modulus (E') and tanδ were measured in tension mode using a dynamic viscoelasticity measuring device DMS6100 (manufactured by Seiko Instruments Inc.) with a sample length of 15 mm, a measurement frequency of 1 Hz, and a temperature range of 20 to 120°C at a heating rate of 2°C / min. ·Pot life The pot life was calculated as the time it took for the viscosity to double from the initial viscosity. The judgment was as follows: ◎: Usable time is 24 hours or more 〇: Usable time is 8 hours or more but less than 16 hours ×: Usable time is less than 8 hours ·viscosity The resin compositions prepared in Examples 1 to 18 and Comparative Examples 1 and 2 were measured using a viscometer "TV-20" (manufactured by Toki Sangyo Co., Ltd.).

[0022] <Evaluation of sealing materials> (Examples 1 to 4, 8) In Examples 1 to 4, the main sealing performance and storage stability were excellent, but differences were observed in viscosity, with Example 2, in which A-187 was added to the silane agent, showing the lowest viscosity. This is thought to be due to the effect of adding a low-molecular-weight silane agent to a hydrogenated bisphenol A epoxy resin, which is a cycloaliphatic epoxy. In Example 8, the main sealing performance and storage stability were comparable to Examples 1 to 4, but the surface of the molded sample was glossier and more flat than the other Examples. Example 5 Although the main sealing performance and storage stability were excellent, the viscosity was slightly higher and the ink resistance was lower compared to Example 2. This is thought to be due to the use of a thiol with an ester structure. (Examples 6 to 7) Although the main sealing performance was excellent, there were differences in that the ink resistance and storage stability were lower compared to Example 2. This is thought to be due to the use of a thiol with an ester structure. (Examples 9 and 13) Although the main sealing performance was excellent, the storage stability was slightly decreased compared to Example 2. This is thought to be because the reactivity during storage was improved due to the increased amount of solid basic compound. Example 10 The main sealing performance and storage stability were excellent, but there was a difference in viscosity, which was higher than that of Example 2. This is thought to be due to the effect of using pre-hydrogenated bisphenol A epoxy resin. Example 11 Although the main sealing performance and storage stability were excellent, differences were observed in viscosity, which was higher than that of Example 2. This is thought to be due to differences in the mixing method, with the silica filler not being sufficiently mixed with the other materials. Example 12 Although the main sealing performance was excellent, differences were observed in storage stability and viscosity. Example 12 had a higher viscosity and lower storage stability than Example 2. This was due to differences in the mixing method, and is thought to be due to the poor mixing of the silica filler and the poor coating ability of the epoxy resin on the solid basic compound. Example 14 The main sealing performance was excellent, and the initial viscosity was also suppressed, which is thought to be due to the increased amounts of silane agent and solid basic compound. (Comparative Examples 1 and 2) In Comparative Examples 1 and 2, an aromatic epoxy resin was used, and therefore the sealing performance was inferior to that of Examples 1 to 12, and the function as a sealing material was not satisfactory.

[0023] [Table 1] In Table 1, for example, the column for post-hydrogenated Bis-A in Example 1 reads "10 A 90B" which means that the amount of post-hydrogenated Bis-A in Mixture A was 10 and that in Mixture B was 90; the column for epoxy amine adduct reads "2 B" which means that the amount of epoxy amine adduct in Mixture B was 2.

[0024] Examples 15 to 18 <Preparation of Composition for Sealant> Table 2 shows the materials used in the examples and their composition ratios. In Examples 15 and 16, a hydrogenated bisphenol A epoxy resin as the main component and a solid basic compound as the catalyst were kneaded to form mixture A. Within one hour, mixture B, which was prepared by kneading the same epoxy resin with a silica filler, and polythiol as the curing agent and a silane agent were added and kneaded (mixture A + B + curing agent + silane agent). In Examples 17 and 18, a hydrogenated bisphenol A epoxy resin as the base material and a solid basic compound as the catalyst were kneaded together to form mixture A. After 12 hours, mixture B, which was a mixture of the same epoxy resin and silica filler, was added to the mixture, along with a polythiol curing agent and a silane agent, and the mixture was kneaded together (mixture A + B + curing agent + silane agent). The epoxy resin as the main component and the thixotropic agent were mixed in a HIVIS MIX model 3 manufactured by Primix Corporation at 1000 rpm for 2 minutes in a vacuum, and all components other than the epoxy resin and the thixotropic agent were mixed at 600 rpm for 5 minutes in a vacuum.

[0025] <Evaluation method for encapsulants> The sealing materials formed using the compositions of Examples 15 to 18 were evaluated as follows. The evaluation results are shown in Tables 3 and 4. ·Pot life The pot life was calculated as the time it took for the viscosity to double from the initial viscosity. The judgment was as follows: 〇: Pot life is 4 hours or more △: Pot life is less than 4 hours The resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were measured using a viscometer "TV-20" (manufactured by Toki Sangyo Co., Ltd.). ·Curing time The curing time was the time it took for the composition to harden at room temperature. The judgment was as follows: 〇: No tackiness after 30 hours at room temperature △: Tacky after 30 hours at room temperature Response rate The reaction rate after 30 hours at room temperature was confirmed by DSC (differential scanning calorimetry).

[0026] <Evaluation of sealing materials> Example 15 In Example 15, the viscosity increased more rapidly over time than in Example 17, as shown in Figure 3, and a high reaction rate was observed after 30 hours at room temperature, as shown in Table 3. This is thought to be because the reactivity was improved by mixing the polythiol within 1 hour after preparing mixture A. Example 16 The initial viscosity was reduced compared to Example 16. This is thought to be due to the increased amounts of the silane agent and solid basic compound. (Examples 17 and 18) In Examples 17 and 18, the storage stability is excellent, but the curing time is longer than that of Examples 15 and 16.

[0027] [Table 2] In Table 2, for example, the column for post-hydrogenated Bis-A in Example 1 reads "10A 90B" which means that the amount of post-hydrogenated Bis-A in Mixture A was 10 and that in Mixture B was 90; the column for epoxy amine adduct reads "10B" which means that the amount of epoxy amine adduct in Mixture B was 10.

[0028] [Table 3]

[0029] [Table 4] [Explanation of symbols]

[0030] 1. Inkjet recording head 2 boards 3. Components 3a Recess side wall 3b recess 4 outlet 5. Encapsulating material

Claims

1. 1. A method for manufacturing an ink jet recording head having a substrate having an ejection port for ejecting a liquid and a member having a recess for accommodating the substrate, the method comprising: a step of producing an encapsulant; and sealing a gap formed between a wall of the recess of the member and the substrate with the sealant, The step of manufacturing the encapsulant includes: a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; A method for manufacturing an ink jet recording head, comprising the step of kneading the mixture 1 with a polythiol to produce a mixture 2.

2. 2. The method for manufacturing an inkjet recording head according to claim 1, wherein the step of manufacturing the sealing material comprises kneading the mixture 1 and the polythiol to manufacture the mixture 2 within one hour after the production of the mixture 1.

3. 1. A method for manufacturing an ink jet recording head having a substrate having an ejection port for ejecting a liquid and a member having a recess for accommodating the substrate, the method comprising: a step of producing an encapsulant; and sealing a gap formed between a wall of the recess of the member and the substrate with the sealant, The step of manufacturing the encapsulant includes: a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A epoxy resin and a silica filler to produce a mixture 3; A method for manufacturing an ink jet recording head, comprising the step of kneading the mixture 1, the mixture 3 and a polythiol to produce a mixture 4.

4. 4. The method for manufacturing an inkjet recording head according to claim 3, wherein the step of manufacturing the sealing material comprises kneading the mixture 1, the mixture 3, and the polythiol to manufacture the mixture 4 within one hour after the production of the mixture 1.

5. 1. A method for manufacturing an ink jet recording head having a substrate having an ejection port for ejecting a liquid and a member having a recess for accommodating the substrate, the method comprising: a step of producing an encapsulant; and sealing a gap formed between a wall of the recess of the member and the substrate with the sealant, The step of manufacturing the encapsulant includes: a step of kneading a hydrogenated bisphenol A epoxy resin and a solid basic compound to produce a mixture 1; a step of kneading a hydrogenated bisphenol A type epoxy resin, a silica filler, and a polythiol to produce a mixture 5; A method for manufacturing an ink jet recording head, comprising the step of kneading the mixture 1 and the mixture 5 to produce a mixture 6.

6. 6. The method for manufacturing an inkjet recording head according to claim 5, wherein the step of manufacturing the sealing material includes kneading the hydrogenated bisphenol A epoxy resin, the silica filler, and the polythiol to manufacture the mixture 5, and kneading the mixture 1 and the mixture 5 to manufacture the mixture 6, within one hour after the production of the mixture 1.

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