Manufacturing method of laminate and manufacturing method of liquid ejection head

Abstract

To provide a method for manufacturing a laminate which enables formation of a nozzle part having a stable shape, and a method for manufacturing a liquid discharge head.SOLUTION: A method for manufacturing a laminate of a cured product of a photosensitive resin composition (1), and a cured product of a photosensitive resin composition (2) includes the steps of: laminating the photosensitive resin composition (2) on the photosensitive resin composition (1), and obtaining a laminated material; exposing the laminated material with light, and obtaining a photocured material; developing the photocured material, and obtaining an object to be developed; and heating the object to be developed, and obtaining a laminate, wherein an exposure amount required for curing the photosensitive resin composition (2) is smaller than an exposure amount required for curing the photosensitive resin composition (1), and the photosensitive resin composition (1) contains an epoxy resin (1) which is an epoxy resin having a weight average molecular weight Mw of 5,000-600,000, a softening point of 140°C or higher, and an epoxy equivalent of 2,300 or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing a laminate and a method for manufacturing a liquid ejection head. [Background technology]

[0002] An example of a laminate formed using a photosensitive resin is a liquid ejection head that ejects liquid. The liquid ejection head is used in a liquid ejection device such as an inkjet recording device, and has a flow path forming member and a substrate. The flow path forming member is provided on the substrate, and forms a liquid flow path and, in some cases, a liquid ejection port. The substrate has an energy generating element on its surface side, and, in some cases, a liquid supply port and an inorganic material layer are formed. The liquid is supplied to the flow path from the liquid supply port, energy is given by the energy generating element, and the liquid is ejected from the liquid ejection port and lands on a recording medium such as paper.

[0003] Patent Document 1 discloses a method for manufacturing a liquid ejection head, in which a low-sensitivity photosensitive resin layer that will become a liquid flow path is provided on a substrate having energy generating elements, and pattern exposure is performed thereon, and then a high-sensitivity photosensitive resin layer that will become a nozzle portion and ejection port is further provided on the low-sensitivity photosensitive resin layer, and pattern exposure is performed thereon, and then the uncured portions are removed to form the liquid flow path, nozzle portion, and ejection port. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 4-216951 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the manufacturing method of the liquid ejection head described in Patent Document 1, during the heat transfer when laminating the high-sensitivity photosensitive resin layer onto the low-sensitivity photosensitive resin layer, or during a thermal process such as a post-exposure bake after the exposure of the high-sensitivity resin layer, compatibility may occur between the laminated photosensitive resin layers, causing diffusion of both compositions. As a result of the diffusion of the low-sensitivity resin layer into the high-sensitivity resin layer, a sensitivity distribution occurs in which the sensitivity decreases toward the interface side in the high-sensitivity resin layer that contacts the low-sensitivity resin layer. After that, after the exposure and development process, the shape of the high-sensitivity part protrudes from the shape of the low-sensitivity high-sensitivity resin layer part, and there is a concern that a slope will be formed in the nozzle part of the high-sensitivity resin layer that becomes the ejection port forming member, as shown in FIG. 5.

[0006] The inclination of the nozzle portion formed by the compatibility between the laminated photosensitive resin layers in this way is difficult to control with precision for each nozzle in the substrate, and may be a cause of variation in the ejection precision in the liquid ejection head. The present disclosure is intended to solve the above problem. That is, the present disclosure provides a method for manufacturing a laminate capable of forming a nozzle portion having a stable shape, and a method for manufacturing a liquid ejection head. [Means for solving the problem]

[0007] The method for producing a laminate according to the present disclosure includes: Photosensitive resin composition (1 )oh Call The amount of exposure required for curing is smaller than that of the photosensitive resin composition (1). Photosensitive resin composition (2) The process of preparing , While heating the photosensitive resin composition (2), The photosensitive resin composition (2) is laminated on the photosensitive resin composition (1). hand Obtaining a laminate, A step of exposing the laminate to light to obtain a photocured product; and A step of developing the photocured product to obtain a developed product. 、 Includes , A method for producing a laminate of a cured product of the photosensitive resin composition (1) and a cured product of the photosensitive resin composition (2), comprising the steps of: before The photosensitive resin composition (1) has a weight average molecular weight Mw of 5,000. 6 or more 00000 belowThe epoxy resin (1) has a softening point of 140°C or higher and an epoxy equivalent of 2300 or lower. It is characterized by:

[0008] Further, a method for manufacturing a liquid ejection head according to the present disclosure includes the steps of: basis On the board Liquid A flow path forming member is formed to form a flow path in the body. A layer of a photosensitive resin composition (1) is provided for the purpose of engineering About the amount of exposure required for curing is less than that of the photosensitive resin composition (1); The flow passage forming portion Material To It is provided, Forming a discharge port forming member having a discharge port for discharging liquid While heating the photosensitive resin composition (2) for the purpose of the present invention, a layer of the photosensitive resin composition (2) is laminated on a layer of the photosensitive resin composition (1) to obtain a laminate. process, A step of exposing the laminate to light to obtain a photocured product; and a step of developing the photocured product to form the flow path forming member and the discharge port forming member; A method for manufacturing a liquid ejection head, comprising: before The photosensitive resin composition (1) has a weight average molecular weight Mw of 5,000. 6 or more 00000 below The epoxy resin (1) has a softening point of 140°C or higher and an epoxy equivalent of 2300 or lower. thing It is characterized by: Effect of the Invention

[0009] According to the above-mentioned configuration, it is possible to provide a method for manufacturing a laminate and a method for manufacturing a liquid ejection head, which are capable of forming a nozzle portion having a stable shape. [Brief description of the drawings]

[0010] [Figure 1] 1A is a schematic perspective view showing an example of the configuration of a laminate (liquid ejection head), and FIG. 1B is a schematic cross-sectional view taken along line AA' in FIG. 1A. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing an example of a method for producing a transfer body having a dry film of the photosensitive resin composition (1). [Diagram 3]1A to 1C are schematic cross-sectional views showing an example of a method for producing a laminate (liquid ejection head). [Figure 4] 1A to 1C are schematic cross-sectional views showing an example of a method for producing a laminate (liquid ejection head) in an embodiment. [Diagram 5] FIG. 1 is a schematic cross-sectional view showing an example of a liquid ejection head according to a conventional technique. [Figure 6] FIG. 2 is a schematic cross-sectional view showing the inclination angle of a nozzle portion of a laminate (liquid ejection head). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, preferred embodiments of the present disclosure will be described with reference to the drawings. In the following description, as an example, a laminate manufacturing method according to the present disclosure is applied to the manufacture of a liquid ejection head, but the laminate manufacturing method according to the present disclosure is not limited to application to the manufacture of a liquid ejection head.

[0012] In the present disclosure, the description of a numerical range such as "XX to YY" or "XX to YY" means a numerical range including the upper and lower limits, which are the endpoints, unless otherwise specified. Furthermore, when a numerical range is described in stages, the upper and lower limits of each numerical range can be arbitrarily combined.

[0013] Furthermore, in the following description, components having the same functions are given the same reference numbers in the drawings, and descriptions thereof may be omitted.

[0014] Fig. 1(A) is a schematic perspective view showing an example of a laminate (liquid ejection head) according to an embodiment of the present disclosure. Fig. 1(B) is a schematic cross-sectional view taken along line A-A' in Fig. 1(A). That is, Fig. 1(B) is a schematic cross-sectional view of the laminate (liquid ejection head) taken along line A-A' in Fig. 1(A) and viewed from a plane perpendicular to the substrate.

[0015] The liquid ejection head shown in Fig. 1 has a substrate 1 having energy generating elements 2 that generate energy for ejecting liquid. The substrate 1 is made of, for example, silicon. The energy generating elements 2 may be formed on the substrate 1 at a predetermined pitch.

[0016] The energy generating element 2 is not particularly limited, and examples thereof include electrothermal conversion elements and piezoelectric elements. The energy generating element 2 may be provided so as to be in contact with the surface of the substrate 1, or may be provided partially hollow with respect to the surface of the substrate 1. The energy generating element 2 may be connected to a control signal input electrode (not shown) for operating the energy generating element 2. The substrate 1 may have a supply port 3 for supplying a liquid such as ink. Specifically, for example, tantalum silicon nitride (TaSiN) can be used as the energy generating element 2. The laminate may not have a substrate, and may not have an energy generating element.

[0017] An inorganic material layer 4 and a protective layer 5 are formed on the surface side of the substrate 1. The substrate 1 is not particularly limited, but may be, for example, a silicon substrate made of silicon. The silicon substrate is preferably a single crystal of silicon, and the crystal orientation of the surface is (100). The inorganic material layer 4 preferably contains at least one selected from the group consisting of silicon oxide (SiO2), silicon nitride (SiN), silicon carbide (SiC), silicon carbonitride (SiCN), silicon carbonate (SiOC), and a metal. The metal is not particularly limited, but may be, for example, gold (Au), iridium (Ir), tantalum (Ta), titanium (Ti), etc. The substrate may or may not have the inorganic material layer, and may or may not have the protective layer.

[0018] In Fig. 1, the inorganic material layer 4 is used as a heat storage layer or an insulating layer. The protective layer 5 protects the energy generating element and may be made of, for example, tantalum (Ta) or iridium (Ir). The inorganic material layer 4 may cover the energy generating element.

[0019] In FIG. 1, the inorganic material layer 4 is formed on almost the entire surface (substrate surface 20) of the substrate 1, but the inorganic material layer 4 may be formed only on a part of the surface (substrate surface 20) of the substrate 1. A flow path 7 may be formed on the inorganic material layer 4 or on the substrate 1, i.e., on the substrate surface 20, by a flow path forming member 6 that forms a liquid flow path. Furthermore, a discharge port forming member 10 having a discharge port 8 that is provided on the flow path forming member and discharges liquid may be formed. The discharge port forming member 10 may have a liquid flow path (nozzle portion 9) that communicates with the discharge port 8. Furthermore, a liquid repellent layer 11 is formed on the discharge port forming member 10 as necessary.

[0020] This liquid ejection head can eject liquid such as ink supplied from a supply port 3 through a flow path 7 as ink droplets from an ejection port 8 via a nozzle portion 9 by applying pressure generated by an energy generating element 2.

[0021] Next, referring to FIG. 2 and FIG. 3, an example of a method for manufacturing a laminate (liquid ejection head) will be specifically described. Fig. 2 is a schematic cross-sectional view illustrating an example of a method for producing a transfer body having a dry film of the photosensitive resin composition (1). Fig. 3 is a schematic cross-sectional view illustrating an example of a method for producing a laminate (e.g., a liquid ejection head). Fig. 3 is a view of the completed state as seen from the position of the cross section, similar to Fig. 1(B).

[0022] First, as shown in Fig. 2(a), a film 12 made of polyethylene terephthalate (PET), polyimide, or the like is prepared. Next, as shown in Fig. 2(b), a photosensitive resin composition (1) 13 is applied to the film 12 by a spin coating method, a slit coating method, or the like, and prebaked to produce a transfer body having a dry film of the photosensitive resin composition (1).

[0023] The photosensitive resin composition (1) 13 contains an epoxy resin (1) having a weight average molecular weight Mw of 5000 to 600000, a softening point of 140° C. or higher, and an epoxy equivalent of 2300 or less. The photosensitive resin composition (1) 13 preferably further contains a photoacid generator and a solvent. The photosensitive resin composition (1) 13 may be a negative photosensitive epoxy resin composition.

[0024] The photosensitive resin composition (1) 13 preferably contains a polyhydric alcohol having difunctional or trifunctional hydroxyl groups at its terminals and not containing a perfluoroalkyl group or a perfluoroalkylene group. The composition of the photosensitive resin composition (1) will be described in detail later.

[0025] In the direction perpendicular to the substrate surface 20, the thickness of the dry film of the photosensitive resin composition (1) 13 corresponds to the height of the flow path. The thickness of the dry film of the photosensitive resin composition (1) 13 may be appropriately determined according to the ejection design of the liquid ejection head so as to be larger than the thickness of the dry film of the photosensitive resin composition (2), and is preferably set to, for example, 3.0 μm to 45.0 μm. The thickness of the flow path forming member is preferably set to 5.0 μm to 40.0 μm.

[0026] A specific method for producing the laminate will be described below, but the method for producing the laminate is not limited to the method described below.

[0027] As shown in Fig. 3(a), a substrate 1 having energy generating elements 2 on its surface side is prepared. Next, as shown in Fig. 3(b), an inorganic material layer 4 is formed on the surface side (on the substrate surface 20) of the substrate 1 so as to cover the energy generating elements 2. In addition, a protective layer 5 is formed above the energy generating elements 2. The inorganic material layer 4 and the protective layer 5 are patterned as necessary.

[0028] 3(c), a supply port 3 is formed through the substrate to supply ink. The supply port 3 is formed at a desired position by wet etching using an alkaline etching solution such as TMAH (tetramethylammonium hydroxide) or dry etching such as reactive ion etching.

[0029] Next, as shown in Fig. 3(d), the transfer body having the dry film of the photosensitive resin composition (1) 13 described in Fig. 2 is transferred onto the inorganic material layer 4 of the substrate 1 on which the energy generating element 2 and the supply port 3 are arranged, by a lamination method to form a film. Thereafter, the film 12 is peeled off from the transfer body having the dry film of the photosensitive resin composition (1) 13 with a release tape or the like, thereby laminating the dry film of the photosensitive resin composition (1) 13 on the substrate 1.

[0030] The method of laminating the photosensitive resin composition (1) 13 on the substrate 1 is not limited to the above-mentioned method of laminating a dry film of the photosensitive resin composition (1) 13, and a cured product such as a heat-cured product or a photocured product of the photosensitive resin composition (1) 13 may be laminated on the substrate 1. In the case of a substrate not having a supply port 3, the photosensitive resin composition (1) may be applied to the substrate by spin coating, slit coating, or the like to form a film, without using a transfer body having a dry film of the photosensitive resin composition (1). The photosensitive resin composition (1) 13 preferably contains a cationic polymerization type epoxy resin, taking into consideration adhesion to the photosensitive resin composition (2) 15 (discharge port forming member 10) described later, mechanical strength, stability against liquids such as ink, resolution, and the like.

[0031] Next, as shown in FIG. 3(e), the photosensitive resin composition (1) 13 is pattern-exposed through a flow path forming mask 14 having a flow path pattern, and then heat-treated (post exposure bake) to photo-cure the exposed areas, thereby forming a flow path forming member 6 which is a cured product of the photosensitive resin composition (1) 13.

[0032] The flow path forming mask 14 may be, for example, a substrate made of a material such as glass or quartz that transmits light of the exposure wavelength, on which a light-shielding film such as a chrome film is formed in accordance with the pattern of the flow path, etc. As the exposure device, for example, a projection exposure device having a single wavelength light source such as an i-line exposure stepper or a KrF stepper, or a broad wavelength light source of a mercury lamp such as the mask aligner MPA-600Super (product name, manufactured by Canon) may be used.

[0033] Next, as shown in FIG. 3(f), photosensitive resin composition (2) 15 is applied to a film substrate made of PET, polyimide, or the like, and then transferred to photosensitive resin composition (1) 13 by a lamination method to form a film, thereby laminating photosensitive resin composition (2) 15 onto the photocured product of photosensitive resin composition (1) 13 to obtain a laminate.

[0034] The photosensitive resin composition (2) 15 that becomes the discharge port forming member 10 preferably contains an epoxy resin, and more preferably contains a cationic polymerization type epoxy resin, in consideration of adhesion to the photosensitive resin composition (1) 13 (flow path forming member 6), mechanical strength, stability against liquids such as ink, resolution, and the like.

[0035] The thickness of the photosensitive resin composition (2) 15 in the direction perpendicular to the substrate surface 20 may be appropriately determined depending on the ejection design of the liquid ejection head, but is preferably, for example, 3.0 μm to 25.0 μm from the viewpoint of mechanical strength, etc. The thickness of the ejection port forming member is preferably 4.5 μm to 20.0 μm.

[0036] If necessary, a liquid-repellent layer 11 may be formed on the photosensitive resin composition (2) 15. By forming the liquid-repellent layer 11 on the photosensitive resin composition (2) 15, it is possible to reduce the water absorption of the discharge port forming member. Since the liquid-repellent layer 11 is required to have liquid repellency against liquids such as ink, it is preferable to use a perfluoroalkyl composition or perfluoropolyether composition having cationic polymerization properties. In the present disclosure, the thickness of the liquid-repellent layer is not included in the thickness of the photosensitive resin composition (2) and the thickness of the discharge port forming member.

[0037] In general, it is known that in perfluoroalkyl compositions and perfluoropolyether compositions, fluorinated alkyl chains segregate at the interface between the composition and air upon baking treatment after application, making it possible to increase the liquid repellency of the surface of the composition.

[0038] 3(g), the photosensitive resin composition (2) 15 and the liquid repellent layer 11 are pattern-exposed through a discharge port forming mask 16 having a discharge port pattern. The exposed portion is then cured by a heat treatment (post exposure bake) to form a discharge port forming member 10, which is a cured product of the photosensitive resin composition (2) 15, to obtain a photocured product.

[0039] When exposing to light having the same wavelength as the photosensitive resin composition (1) 13, the amount of exposure required to cure the photosensitive resin composition (2) 15 must be less than the amount of exposure required to cure the photosensitive resin composition (1) 13. If the amount of exposure required to cure the photosensitive resin composition (2) 15 is equal to or greater than the amount of exposure required to cure the photosensitive resin composition (1) 13, the light transmitted through the photosensitive resin composition (2) 15 will photocure the photosensitive resin composition (1) 13 when exposing the photosensitive resin composition (2) 15, making it difficult to remove the unexposed portion of the photosensitive resin composition (1) 13 to form the flow path 7 in the development step described below.

[0040] The discharge port forming mask 16 may be, for example, a substrate made of a material such as glass or quartz that transmits light of the exposure wavelength, on which a light-shielding film such as a chrome film is formed in accordance with the discharge port pattern. As the exposure device, for example, a projection exposure device having a single wavelength light source such as an i-line exposure stepper or a KrF stepper, or a broad wavelength light source of a mercury lamp such as the mask aligner MPA-600Super (product name, manufactured by Canon) may be used.

[0041] Next, as shown in Fig. 3(h), the photocured product is developed to obtain a developed object. That is, the photosensitive resin composition (1) 13, the photosensitive resin composition (2) 15, and the uncured parts of the liquid-repellent layer 11 are developed with a developer to remove them all at once, thereby forming the flow path 7, the discharge port 8, and the nozzle part 9.

[0042] Thereafter, the developed object is heated, i.e., the developed object is subjected to a heat treatment (Post Exposure Bake) to obtain a laminate (liquid ejection head). Examples of the developing solution include PGMEA (propylene glycol monomethyl ether acetate), MIBK (methyl isobutyl ketone), xylene, etc. If necessary, a rinse treatment using IPA (isopropyl alcohol) or the like may be performed.

[0043] In the above-mentioned method for producing the laminate, the photosensitive resin composition (2) 15 is laminated on the photosensitive resin composition (1) 13 after exposing the photosensitive resin composition (1) 13, but it is also possible to laminate the photosensitive resin composition (2) 15 on the photosensitive resin composition (1) 13 before exposing the photosensitive resin composition (1) 13. That is, the process for obtaining the laminate is not limited to the method of laminating the photosensitive resin composition (2) 15 on the photocured product of the photosensitive resin composition (1) 13, and the laminate may be obtained by laminating the photosensitive resin composition (2) 15 on the undried photosensitive resin composition (1) 13, a dry film of the photosensitive resin composition (1) 13, or a heat-cured product of the photosensitive resin composition (1) 13.

[0044] In the above-mentioned method for manufacturing the laminate, the flow path forming member 6 and the discharge port forming member 10 are formed in two layers, but the present disclosure is not limited to this form. Furthermore, a configuration of three or more layers may be formed using a plurality of photosensitive resin compositions, and the flow path forming member and the discharge port forming member may be formed using a plurality of photosensitive resin compositions.

[0045] The photosensitive resin composition will be described below. The photosensitive resin composition (1) contains an epoxy resin having a weight average molecular weight (Mw) of 5000 to 600000, a softening point of 140° C. or more, and an epoxy equivalent of 2300 or less (hereinafter, an epoxy resin satisfying all of these three requirements is also referred to as "epoxy resin (1)"). The content of the epoxy resin (1) in the dry film of the photosensitive resin composition (1) is preferably 20% by mass to 90% by mass, more preferably 25% by mass to 80% by mass. The photosensitive resin composition (1) may contain an epoxy resin other than the epoxy resin (1).

[0046] When the laminate of the present disclosure is applied to a liquid ejection head obtained by thermally transferring a photosensitive resin composition onto a substrate and laminating the same, the photosensitive resin composition (1) contains the above-mentioned epoxy resin (1). In addition, the photosensitive resin composition (2) has resistance (heat resistance) to the heat process in the manufacturing process of the liquid ejection head, and the pattern shape of the nozzle part of the ejection port forming member is stable. Specifically, the photosensitive resin composition (2) has a higher sensitivity than the photosensitive resin composition (1), and the photosensitive resin composition (2) has a higher heat resistance in the heating process during transfer and lamination, and in the heat treatment after exposure (Post Even if the laminated photosensitive resin compositions (1) and (2) are subjected to a thermal process such as exposure bake, diffusion of both compositions between the laminated photosensitive resin compositions (1) and (2) can be prevented.

[0047] When the weight average molecular weight (Mw) of the epoxy resin (1) is less than 5000 or the softening point of the epoxy resin (1) is less than 140°C, the photosensitive resin composition (2) 15, which is more sensitive than the photosensitive resin composition (1), may diffuse between the laminated photosensitive resin layers due to heating during transfer and lamination or heat treatment after exposure (Post Exposure Bake). On the other hand, when the weight average molecular weight (Mw) of the epoxy resin (1) is greater than 600,000, the crosslink density of the photosensitive resin composition (1) is excessively reduced, and the stability of the pattern shape is reduced. In addition, when the epoxy equivalent of the epoxy resin (1) is greater than 2300, the reactivity is reduced, and defects such as unevenness on the sidewall of the pattern of the cured product occur.

[0048] The epoxy resin (1) is not particularly limited as long as it has a weight average molecular weight (Mw) of 5,000 to 600,000, a softening point of 140° C. or higher, and an epoxy equivalent of 2,300 or less. For example, Mitsubishi Chemical Corporation's “jER1009F” and “jER1009SK” can be used.

[0049] The weight average molecular weight (Mw) of the epoxy resin (1) is preferably 10,000 to 60,000, and more preferably 20,000 to 30,000. The softening point of the epoxy resin (1) is preferably 140° C. to 200° C., and more preferably 142° C. to 180° C. The epoxy equivalent of the epoxy resin (1) is preferably 1,000 to 2,300, and more preferably 1,500 to 2,300.

[0050] The photosensitive resin composition (1) is preferably a cationic polymerization type epoxy resin composition in consideration of the adhesion performance, mechanical strength, liquid (ink) resistance, swelling resistance, reactivity as a photolithography material, resolution, etc. of the cured product. More specifically, the photosensitive resin composition (1) preferably contains an epoxy resin having at least one skeleton selected from the group consisting of a bisphenol skeleton such as bisphenol A type or bisphenol F type, a phenol novolac skeleton, a cresol novolac skeleton, a norbornene skeleton, a terpene skeleton, a dicyclopentadiene skeleton, and an oxycyclohexane skeleton. When the epoxy resin contained in the photosensitive resin composition (1) has the above skeleton, the cured product of the photosensitive resin composition (1) is three-dimensionally crosslinked, which is suitable for obtaining desired properties.

[0051] Furthermore, from the viewpoint of resolution, the dispersity (Mw / Mn), which is the ratio of the weight average molecular weight Mw to the number average molecular weight Mn of the epoxy resin (1), is preferably less than 3.0. When Mw / Mn is less than 3.0, the reactivity of the epoxy resin is improved. As a result, sufficient curing of the epoxy resin (1) is likely to occur, and defects such as unevenness on the pattern sidewall of the cured product of the photosensitive resin composition (1) 13 caused by the uncured epoxy resin (1) eluting during development are unlikely to occur. The dispersity is more preferably 2.0 or more and 2.8 or less.

[0052] The weight average molecular weight and number average molecular weight of the epoxy resin (1) can be calculated in terms of polystyrene using gel permeation chromatography (for example, manufactured by Shimadzu Corporation). The detailed measurement method will be described later.

[0053] From the viewpoint of reactivity, the photosensitive resin composition (1) 13 preferably contains a trifunctional or higher epoxy resin and a difunctional epoxy resin, and the difunctional epoxy resin is more preferably the above-mentioned epoxy resin (1). By including an epoxy resin, crosslinking progresses three-dimensionally, improving the sensitivity of the photosensitive material.

[0054] The tri- or higher functional epoxy resin preferably has an epoxy equivalent of less than 500. When the epoxy equivalent of the tri- or higher functional epoxy resin is less than 500, the sensitivity is insufficient, which makes it difficult for the pattern resolution to decrease and the mechanical strength and adhesion of the cured product to decrease.

[0055] In addition, the mass mixing ratio of the trifunctional or higher epoxy resin to the difunctional epoxy resin in the photosensitive resin composition (1) 13 (difunctional epoxy resin / trifunctional or higher epoxy resin) is preferably 0.3 or more and less than 5.0 from the viewpoint of heat resistance and adhesion. The mass mixing ratio is more preferably 0.4 to 4.0.

[0056] By setting the mass mixing ratio of the trifunctional or higher epoxy resin and the bifunctional epoxy resin in the photosensitive resin composition (1) 13 within the above range, the diffusion of both compositions between the laminated photosensitive resin layers is more prevented. Furthermore, when the mass mixing ratio is 0.3 or more, the heat resistance is more suitable. Furthermore, when the mass mixing ratio is 5.0 or less, swelling when contacting with a liquid such as ink is small, and the adhesion is less likely to decrease.

[0057] In addition, from the viewpoint of adhesion to the inorganic material layer 4, the photosensitive resin composition (1) 13 preferably contains a polyhydric alcohol, and more preferably the polyhydric alcohol is a polyhydric alcohol having a difunctional or trifunctional hydroxyl group at the end. By containing a polyhydric alcohol having a difunctional or trifunctional hydroxyl group at the end, it is possible to promote the cationic polymerization reaction of the epoxy resin and reduce the stress of the cured resin due to the reaction between the ring-opened epoxy group and the hydroxyl group, which is effective in improving adhesion to the inorganic material layer. The terminal hydroxyl group of the polyhydric alcohol is preferably difunctional or trifunctional, and more preferably difunctional. When the terminal hydroxyl group is difunctional, the effect of promoting the cationic polymerization reaction of the epoxy resin is large, and the adhesion to the inorganic material layer is less likely to decrease when contacting with a solvent or ink.

[0058] Furthermore, it is more preferable that the polyhydric alcohol does not contain a perfluoroalkyl group or a perfluoroalkylene group. If the polyhydric alcohol does not contain a perfluoroalkyl group or a perfluoroalkylene group, segregation to the air interface side after film formation, which reduces adhesion to the inorganic material layer, is unlikely to occur. Furthermore, if the polyhydric alcohol does not contain a perfluoroalkyl group or a perfluoroalkylene group, when the photosensitive resin composition (1) is used as a dry film or a cured product such as a thermally cured product and a photocured product, there will be no polyhydric alcohol containing a perfluoroalkyl group or a perfluoroalkylene group segregated on the surface in contact with the inorganic material layer, and adhesion to the inorganic material layer is unlikely to decrease.

[0059] More preferably, the photosensitive resin composition (1) 13 contains a polyhydric alcohol having difunctional or trifunctional hydroxyl groups at its terminals and not containing a perfluoroalkyl group or a perfluoroalkylene group. It is particularly preferable that the terminal hydroxyl groups of the polyhydric alcohol are difunctional.

[0060] The molecular weight of the polyhydric alcohol contained in the photosensitive resin composition (1) is preferably less than 3000. When the molecular weight is less than 3000, the ratio of the hydroxyl group equivalent in the molecule increases, and the effect of improving the adhesion is also large. Kuna In addition, the resolution of the photolithography material is unlikely to decrease.

[0061] In addition, the polyhydric alcohol contained in the photosensitive resin composition (1) is not lost during heating steps such as pre-baking and PEB before the development step during the production of a laminate. In order to avoid such a problem, it is preferable that the solvent has a boiling point higher than the temperature of the heating step. The boiling point can be, for example, 210° C. or higher. Also, the boiling point can be, for example, 500° C. or lower.

[0062] The content of the polyhydric alcohol in the photosensitive resin composition (1) is preferably 0.5 parts by mass to 4.0 parts by mass, more preferably 1.0 parts by mass to 3.6 parts by mass, based on 100 parts by mass of the total mass of all epoxy resins contained in the photosensitive resin composition (1). When the content is 0.5 parts by mass or more, the effect of improving the adhesion with the inorganic material layer is increased. When the content is 4.0 parts by mass or less, the decrease in resolution as a photolithography material can be suppressed.

[0063] The photosensitive resin composition (2) 15 is not particularly limited as long as the exposure dose required for curing the photosensitive resin composition (2) is less than the exposure dose required for curing the photosensitive resin composition (1), and a known photosensitive resin composition can be used. The photosensitive resin composition (2) 15 preferably contains an epoxy resin, a photoacid generator, and a solvent. In addition, the epoxy resin contained in the photosensitive resin composition (2) is more preferably a trifunctional or higher epoxy resin from the viewpoint of the mechanical strength of the cured product of the photosensitive resin composition (2). Furthermore, from the viewpoint of reactivity, the epoxy equivalent of the epoxy resin contained in the photosensitive resin composition (2) is preferably 500 or less, more preferably 0 to 300.

[0064] Examples of commercially available epoxy resins other than the epoxy resin (1) that can be used in the photosensitive resin composition (1) 13 include, for example, “Celloxide 2021”, “GT-300 series”, “GT-400 series”, and “EHPE3150” (product names) manufactured by Daicel Chemical Industries, Ltd., “jER1031S”, “jER1004”, “jER1007”, “jER1009”, “jER1010”, “jER1256”, and “157S70” (product names) manufactured by Mitsubishi Chemical Corporation, and “EPICLON N-695”, “EPICLON N-865”, “EPICLON 4050”, “EPICLON 7050”, “EPICLON HP-6000”, “EPICLON HP-4710”, “EPICLON HP-7200 series”, and “EPICLON Examples of commercially available epoxy resins that can be used in the photosensitive resin composition (2) 15 include "EXA-4816" (trade name), "EPOX-MKR1710" (trade name), "Denacol series" (trade name) manufactured by Nagase ChemteX Corporation, and "EP-4000 series" (trade name) manufactured by ADEKA Corporation. In addition to the above-mentioned epoxy resins, resins that fall under the category of epoxy resin (1), such as "jER1009F" and "jER1009SK" manufactured by Mitsubishi Chemical Corporation, can be used. Two or more of these epoxy resins can also be used in combination.

[0065] The content of the epoxy resin in the dry film of the photosensitive resin composition (2) is preferably 80% by mass to 98% by mass. The photosensitive resin composition (1) or the photosensitive resin composition (2) may contain a photosensitive resin other than the epoxy resin.

[0066] Examples of photoacid generators that may be included in the photosensitive resin composition (1) include sulfonic acid compounds, diazomethane compounds, sulfonium salt compounds, iodonium salt compounds, and disulfone compounds. Commercially available products include ADEKA Optomer SP-170, ADEKA Optomer SP-172, and SP-150 (trade names), Midori Chemical Co., Ltd.'s BBI-103 and BBI-102 (trade names), Sanwa Chemical Co., Ltd.'s IBP F, IBC F, TS-01, and TS-91 (trade names), San-Apro Co., Ltd.'s CPI-210, CPI-300, and CPI-410 (trade names), and BASF Japan's Irgacure 290 (trade name). Two or more of these photoacid generators may be used in combination. The content of the photoacid generator in the dry film of the photosensitive resin composition (1) is preferably 2% by mass to 8% by mass.

[0067] The photoacid generator that can be contained in the photosensitive resin composition (2) is the same as the photoacid generator that can be contained in the photosensitive resin composition (1). Use The content of the photoacid generator in the dry film of the photosensitive resin composition (2) is preferably 0.1% by mass to 4% by mass.

[0068] For the purpose of adjusting the amount of exposure required to cure the photosensitive resin composition (1) or (2), the type and content of the photoacid generator can be adjusted.

[0069] Furthermore, for the purpose of improving adhesion performance, at least one of the photosensitive resin composition (1) and the photosensitive resin composition (2) may contain a silane coupling agent. The silane coupling agent is not particularly limited, but examples of commercially available silane coupling agents include "A-187" (trade name) manufactured by Momentive Performance Materials, Inc. The content of the silane coupling agent in the dry film of the photosensitive resin composition (1) is preferably 1.5% by mass to 10.0% by mass. The content of the silane coupling agent in the dry film of the photosensitive resin composition (2) is preferably 0.5% by mass to 3.0% by mass.

[0070] In addition, for the purpose of improving pattern resolution and adjusting sensitivity (exposure dose required for curing), it is also possible to add a sensitizer such as an anthracene compound, a basic substance such as an amine, an acid generator that generates a weak acidic substance (pKa=-1.5 to 3.0) such as toluenesulfonic acid, a quencher, etc. Commercially available acid generators that generate toluenesulfonic acid include "TPS-1000" (trade name) manufactured by Midori Chemical Industry Co., Ltd. and "WPAG-367" (trade name) manufactured by Wako Pure Chemical Industries, Ltd.

[0071] In addition, commercially available negative photoresists such as "SU-8 series" and "KMPR-1000" (product names) manufactured by Kayaku MicroChem Corporation, and "TMMR S2000" and "TMMF S2000" (product names) manufactured by Tokyo Ohka Kogyo Co., Ltd. can be used as the photosensitive resin composition (1) or the photosensitive resin composition (2). EXAMPLES

[0072] Hereinafter, the present disclosure will be described in detail with reference to examples and comparative examples, but the present disclosure is not limited to the configurations embodied in these examples. Furthermore, "parts" used in the examples and comparative examples means "parts by mass" unless otherwise specified.

[0073] [Production Example of Photosensitive Resin Composition (1)] Photosensitive resin compositions (1)-1 to (1)-11 shown in Table 1 were prepared. [Table 1]

[0074] In the table, EPICLON N695: Manufactured by DIC jER1009F, jER1009SK: Manufactured by Mitsubishi Chemical Corporation PEG: Polyethylene glycol CPI-410S: San-Apro SP-172: ADEKA TPS-1000: Midori Chemical Co., Ltd. A-187: Momentive Performance Materials ·PGMEA: Propylene glycol monomethyl ether acetate

[0075] [Example 1] First, as shown in Fig. 4(a), a 100 μm thick PET film 12 was prepared. Next, as shown in Fig. 4(b), the photosensitive resin composition (1)-1 (13 in Fig. 4(b)) shown in Table 1 was applied onto the PET film 12 by spin coating, and baked at 90°C for 20 minutes to volatilize the solvent, forming a 15.0 μm thick film (dry film).

[0076] Next, as shown in Fig. 4(c), a substrate 1 made of silicon having energy generating elements 2 made of TaSiN on the surface side was prepared. Next, as shown in Fig. 4(d), an inorganic material layer 4 of SiCN was formed to a thickness of 0.3 µm on the surface side (substrate surface 20 side) of the substrate 1 by plasma CVD so as to cover the energy generating elements 2. Then, a protective layer 5 of Ta was formed to a thickness of 0.25 µm by sputtering. Furthermore, the inorganic material layer 4 and the protective layer 5 were patterned by a photolithography process and reactive ion etching.

[0077] Next, supply port 3 was formed as shown in FIG. 4(e). Supply port 3 was formed by forming an etching mask having an opening using a positive photosensitive resin made of OFPR (manufactured by Tokyo Ohka Kogyo Co., Ltd.) and performing reactive ion etching through the opening of the etching mask. The reactive ion etching was performed by the Bosch process using an ICP etching device (manufactured by Alcatel, model number: 8E). After the supply port 3 was formed, the etching mask was removed using a stripping solution.

[0078] Next, as shown in FIG. 4(f), a layer of photosensitive resin composition (1)-1 (13 in FIG. 4(f)) was formed. Specifically, the PET film having the photosensitive resin composition (1)-1 prepared in FIG. 4(b) was transferred to the substrate 1 on which the energy generating element 2 and the supply port 3 were arranged, while applying heat of 80°C and pressure using a lamination method. Thereafter, the PET film 12 was peeled off from the photosensitive resin composition (1)-1 with a peeling tape (not shown).

[0079] Next, as shown in FIG. 4( g ), the photosensitive resin composition (1)-1 is exposed through a flow path forming mask 14 having a flow path pattern to an i-line exposure stepper (Canon, product name: i5) at 16000 J / m 2 The exposed portion was cured by performing a heat treatment at 50° C. for 5 minutes, thereby forming a flow path forming member 6, which was a cured product (photocured product in this example) of the photosensitive resin composition (1).

[0080] Next, as shown in FIG. 4(h), a photosensitive resin composition (2) 15 was formed. First, a photosensitive resin composition (2) 15 consisting of the composition materials shown in Table 2 below was applied onto a PET film having a thickness of 100 μm, and baked at 90° C. for 5 minutes to volatilize the solvent, forming a 5.0 μm film (dry film). Next, the photosensitive resin composition (2) 15 was transferred and laminated onto the photosensitive resin composition (1)-1 and the flow path forming member 6 while applying heat of 50° C. using a lamination method, to obtain a laminate. [Table 2]

[0081] In the table, jER157S70: Mitsubishi Chemical Corporation

[0082] Next, as shown in FIG. 4(i), a photosensitive resin composition (2) 15 is exposed through a discharge port forming mask 16 having a discharge port pattern, at 1100 J / m using an i-line exposure stepper (Canon, product name: i5). 2 The exposed portion was then cured by performing a heat treatment at 90° C. for 5 minutes, thereby forming a discharge port forming member 10, which was a cured product (a photocured product in this example) of the photosensitive resin composition (2), to obtain a photocured product.

[0083] 4(j), the uncured portion of the photosensitive resin composition (1)-1 and the uncured portion of the photosensitive resin composition (2) 15 were developed with PGMEA for 1 hour to remove them all at once, and a flow path 7, a discharge port 8, and a nozzle portion 9 were formed to obtain a developed object. The developed object was cured by heating at 200° C. to obtain a laminate (liquid discharge head).

[0084] [Examples 2 to 11] Laminates (liquid ejection heads) of Examples 2 to 11 were obtained in the same manner as in Example 1, except that photosensitive resin compositions (1)-2 to (1)-11 were used instead of the photosensitive resin composition (1)-1.

[0085] [Production Example of Photosensitive Resin Composition (1)] Photosensitive resin compositions (1)-12 to (1)-13 shown in Table 1 were prepared.

[0086] [Comparative Examples 1 and 2] Laminates (liquid ejection heads) of Comparative Examples 1 and 2 were obtained in the same manner as in Example 1, except that photosensitive resin compositions (1)-12 to (1)-13 were used instead of the photosensitive resin composition (1)-1. [Table 3]

[0087] [evaluation] <Tilt angle of ejection port> The fabricated laminate (liquid ejection head) was cut across the ejection port, and the cross-sectional shape of the ejection port was observed at a magnification of 10,000 times using a scanning electron microscope (Hitachi, product name: S-4800). The angle at the point indicated by reference numeral 17 in FIG. 6 was measured as the tilt angle of the nozzle portion, and the ejection port shape was evaluated. The evaluation results are summarized in Table 4.

[0088] <Patterning ability> The pattern sidewalls of the flow path forming member 6, the flow path 7, and the discharge port forming member 10 of the produced laminate (liquid discharge head) were observed at a magnification of 5000 times using a scanning electron microscope (manufactured by Hitachi, Ltd., product name: S-4800) to evaluate the patterning ability according to the following criteria. The evaluation results are summarized in Table 4. None: No unevenness on the pattern sidewall Yes: Pattern sidewalls are uneven In the laminates (liquid ejection heads) of Examples 1 to 11, no irregularities were observed on the pattern sidewalls, the pattern shape was good, and excellent patterning properties were obtained.

[0089] <Printing evaluation> The prepared laminate (liquid ejection head) was filled with ink consisting of ethylene glycol / urea / isopropyl alcohol / N-methylpyrrolidone / black dye / water = 5 / 3 / 2 / 5 / 3 / 82 (mass ratio), printed in an environment of 30°C and 80% RH, and the probability of dots being printed with a warp was evaluated visually. In the printing test, the letter "H" was printed continuously on 100 A4 sheets so that the printing rate was 40%, and if even one warp occurred on the A4 sheets, it was determined that there was print warp, and the occurrence probability was calculated and the print quality was evaluated according to the following criteria. Good: The probability of print distortion is 3% or less. Deterioration: The probability of print distortion exceeds 3% [Table 4]

[0090] The laminates (liquid ejection heads) of Examples 1 to 11 had good print quality. On the other hand, the laminate (liquid ejection head) of Comparative Example 1 had good patterning properties with no irregularities on the pattern sidewalls, but the inclination angle of the nozzle part was large. Furthermore, the laminate (liquid ejection head) of Comparative Example 2 had irregularities on the pattern sidewalls and a large inclination angle of the nozzle part. The laminates (liquid ejection heads) of Comparative Examples 1 and 2 had inferior print quality to the laminates (liquid ejection heads) of Examples 1 to 11 due to the influence of the variation in the inclination angle of the nozzle part. As described above, according to the present disclosure, it is possible to provide a laminate manufacturing method capable of forming a nozzle portion having a stable shape, and the laminate. [Explanation of symbols]

[0091] 1 substrate, 2 energy generating element, 3 supply port, 4 inorganic material layer, 5 protective layer, 6 flow path forming member, 7 flow path, 8 discharge port, 9 nozzle portion, 10 discharge port forming member, 11 liquid repellent layer, 12 film, 13 photosensitive resin composition (1), 14 flow path forming mask, 15 photosensitive resin composition (2), 16 discharge port forming mask, 17 inclination angle of nozzle portion, 20 Board surface

Claims

1. A step of preparing a photosensitive resin composition (1) and a photosensitive resin composition (2) which requires a smaller amount of exposure to light for curing than the photosensitive resin composition (1); a step of laminating the photosensitive resin composition (2) on the photosensitive resin composition (1) while heating the photosensitive resin composition (2) to obtain a laminate; A step of exposing the laminate to light to obtain a photocured product; and A step of developing the photocured product to obtain a developed product; A method for producing a laminate of a cured product of the photosensitive resin composition (1) and a cured product of the photosensitive resin composition (2), comprising: The photosensitive resin composition (1) contains an epoxy resin (1) having a weight average molecular weight Mw of 5,000 or more and 600,000 or less, a softening point of 140° C. or more, and an epoxy equivalent of 2,300 or less. A method for producing a laminate comprising the steps of:

2. The photosensitive resin composition (1) further contains a photoacid generator, 2. The method for producing a laminate according to claim 1, wherein the photosensitive resin composition (2) contains an epoxy resin and a photoacid generator.

3. The method for producing a laminate according to claim 1 or 2, wherein the photosensitive resin composition (1) contains a tri- or higher functional epoxy resin and a difunctional epoxy resin.

4. 4. The method for producing a laminate according to claim 3, wherein a mass mixing ratio of the tri- or higher functional epoxy resin to the difunctional epoxy resin in the photosensitive resin composition (1) (mass of the difunctional epoxy resin / mass of the tri- or higher functional epoxy resin) is 0.3 or more and 5.0 or less.

5. A method for manufacturing a laminate as described in claim 4, wherein the mass mixing ratio is 1.0 or more and 5.0 or less.

6. A method for manufacturing a laminate as described in claim 4, wherein the mass mixing ratio is 2.0 or more and 5.0 or less.

7. The photosensitive resin composition (1) has a bisphenol skeleton, a phenol novolac skeleton, The method for producing a laminate according to any one of claims 1 to 6, comprising an epoxy resin having at least one skeleton selected from the group consisting of a resol novolac skeleton, a norbornene skeleton, a terpene skeleton, a dicyclopentadiene skeleton, and an oxycyclohexane skeleton.

8. The method for producing a laminate according to any one of claims 1 to 7, wherein the photosensitive resin composition (1) contains a polyhydric alcohol having difunctional or trifunctional hydroxyl groups at its terminals and not containing a perfluoroalkyl group or a perfluoroalkylene group.

9. 9. The method for producing a laminate according to claim 8, wherein a content of the polyhydric alcohol in the photosensitive resin composition (1) is 0.5 parts by mass or more and 4.0 parts by mass or less per 100 parts by mass of the total mass of all epoxy resins contained in the photosensitive resin composition (1).

10. 10. The method for producing a laminate according to claim 8 or 9, wherein the content of the polyhydric alcohol in the photosensitive resin composition (1) is 1.0 part by mass or more and 3.6 parts by mass or less per 100 parts by mass of the total mass of all epoxy resins contained in the photosensitive resin composition (1).

11. The laminate further comprises a substrate having an energy generating element; The method for producing a laminate according to any one of claims 1 to 10, further comprising a step of laminating the photosensitive resin composition (1) on the substrate.

12. The method for producing a laminate according to claim 11 , wherein the substrate has an inorganic material layer.

13. The method for producing a laminate according to claim 12, wherein the inorganic material layer contains at least one selected from the group consisting of silicon oxide, silicon nitride, silicon carbide, silicon carbonitride, silicon carbonate, and a metal.

14. The method for producing a laminate according to any one of claims 11 to 13, wherein the substrate has a supply port.

15. The method for producing a laminate according to any one of claims 1 to 14, wherein the ratio (Mw / Mn) of the weight average molecular weight Mw to the number average molecular weight Mn of the epoxy resin (1) is less than 3.

0.

16. A method for manufacturing a laminate described in any one of claims 1 to 15, wherein the photosensitive resin composition (1) and the photosensitive resin composition (2) are dry films.

17. A method for producing a laminate described in any one of claims 1 to 16, wherein the content of the epoxy resin (1) in the photosensitive resin composition (1) is 20 mass% or more and 90 mass% or less.

18. A method for producing a laminate described in any one of claims 1 to 17, comprising a step of exposing the photosensitive resin composition (1) to light prior to the step of obtaining the laminate.

19. A method for producing a laminate described in any one of claims 1 to 18, wherein the epoxy resin (1) is a difunctional epoxy resin.

20. A step of providing a layer of a photosensitive resin composition (1) for forming a flow path forming member that forms a liquid flow path on a substrate; a step of laminating a layer of the photosensitive resin composition (2) on a layer of the photosensitive resin composition (1) while heating the photosensitive resin composition (2) for forming a discharge port forming member having a discharge port for discharging a liquid, the photosensitive resin composition (2) requiring a smaller amount of exposure to light for curing than the photosensitive resin composition (1) and provided on the flow path forming member; A step of exposing the laminate to light to obtain a photocured product; and a step of developing the photocured product to form the flow path forming member and the discharge port forming member; A method for manufacturing a liquid ejection head, comprising: The photosensitive resin composition (1) contains an epoxy resin (1) having a weight average molecular weight Mw of 5,000 or more and 600,000 or less, a softening point of 140° C. or more, and an epoxy equivalent of 2,300 or less. A method for manufacturing a liquid ejection head comprising the steps of:

21. A method for manufacturing a liquid ejection head as described in claim 20, wherein the photosensitive resin composition (1) contains a trifunctional or higher epoxy resin and a difunctional epoxy resin.

22. A method for manufacturing a liquid ejection head as described in Claim 21, wherein the mass mixing ratio of the tri- or higher functional epoxy resin to the difunctional epoxy resin in the photosensitive resin composition (1) (mass of the difunctional epoxy resin / mass of the tri- or higher functional epoxy resin) is 0.3 or more and 5.0 or less.

23. A method for manufacturing a liquid ejection head as described in claim 22, wherein the mass mixing ratio is 1.0 or more and 5.0 or less.

24. A method for manufacturing a liquid ejection head as described in claim 22, wherein the mass mixing ratio is 2.0 or more and 5.0 or less.

25. A method for manufacturing a liquid ejection head described in any one of claims 20 to 24, wherein the photosensitive resin composition (1) and the photosensitive resin composition (2) are dry films.

26. A method for manufacturing a liquid ejection head described in any one of claims 20 to 25, wherein the content of the epoxy resin (1) in the photosensitive resin composition (1) is 20 mass% or more and 90 mass% or less.

27. ​​A method for manufacturing a liquid ejection head described in any one of claims 20 to 26, comprising a step of exposing the photosensitive resin composition (1) to light prior to the step of obtaining the laminate.

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