Ink jet recording head

Abstract

To provide an inkjet recording head excellent in blade wipe durability.SOLUTION: An ink jet recording head comprising a silicone-containing film on a face on which an ejection orifice is provided, wherein the silicone-containing film is etched with 40kV + by applying an acceleration voltage C60 in a thickness direction perpendicular to the face of the silicone-containing film, and the composition of the face of the silicone-containing film etched with SiC3H9 + is analyzed by time-of-flight secondary ion mass spectrometry (ToF-SIMS). 0s, the value of the ratio of the amount of 30s + present at the SiC3H9 of the etching time is 0.70 or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an inkjet print head. [Background technology]

[0002] Fluorine-based water-repellent materials are generally known as materials for forming liquid-repellent and stain-resistant films. Compounds containing perfluoroalkyl or perfluoropolyether groups, in particular, have excellent liquid-repellent and durability properties and are widely used in a variety of applications. However, because fluorine-containing compounds are highly chemically stable and persistent, if they are continuously released into the environment, they may remain in the environment for long periods of time, potentially affecting human health and the habitat and growth of plants and animals through the environment and food chain. Therefore, in recent years, there has been a demand for a shift from fluorine-based water-repellent materials to non-fluorine-based water-repellent materials in order to realize a sustainable society, such as a recycling-oriented society.

[0003] Silicone compounds are fluorine-free water repellents that exhibit excellent liquid repellency and can be used as an alternative to fluorine-based water repellents. Silicone compounds can eliminate concerns about environmental impact and fluorine sources. For example, Patent Document 1 discloses a method using a silicone compound, particularly a siloxane-containing epoxy resin composition, as a non-fluorine-based water repellent material. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-158818 Summary of the Invention [Problem to be solved by the invention]

[0005] Fluorine-based, silicone-based, and other water-repellent materials may exhibit water-repellent properties by segregating water-repellent groups on the surface of the water-repellent film. As shown in Patent Document 1, the comb-shaped water-repellent structure allows for a large degree of freedom in the silicone, and the siloxane main chain segregates on the surface when the film is formed. This can result in insufficient durability, and for example, it is not possible to achieve blade wipe durability that is suitable for commercial and industrial printing.

[0006] Therefore, the present disclosure provides an inkjet recording head with excellent blade wipe durability suitable for commercial and industrial printing. [Means for solving the problem]

[0007] The present disclosure provides an inkjet recording head, the ink jet recording head has a silicone-containing film on a surface where the ejection ports are provided, An acceleration voltage of 40 kV was applied to the silicon-containing film in the thickness direction perpendicular to the surface. + When the surface of the silicon-containing film etched using the etching method was subjected to composition analysis by time-of-flight secondary ion mass spectrometry ToF-SIMS, the SiC3H9 + The amount of SiC3H9 at an etching time of 30 seconds + The ratio of abundances of is 0.70 or more, The present invention relates to an inkjet recording head in which the contact angle on the outermost surface of the silicone-containing film is 80° or more. [Effects of the Invention]

[0008] According to the present disclosure, an inkjet recording head having excellent blade wipe durability suitable for commercial and industrial printing is provided. [Brief explanation of the drawings]

[0009] [Figure 1] 1A and 1B are schematic diagrams of an inkjet recording head using a silicone-containing film. [Figure 2]2A to 2H are diagrams illustrating an example of a method for manufacturing an inkjet recording head using a silicone-containing film. [Figure 3] 3A and 3B are diagrams for explaining the procedure for forming a silicone-containing film. [Figure 4] 4A and 4B are schematic diagrams of an ink jet recording head using a silicone-containing film. [Figure 5] 5A to 5D are schematic diagrams showing a method for forming a water-repellent film on a discharge port. [Figure 6] FIG. 6 is a diagram showing the count number of each ion as a function of etching time. DETAILED DESCRIPTION OF THE INVENTION

[0010] In the present disclosure, expressions such as "XX or more and YY or less" or "XX to YY" representing a numerical range mean a numerical range including the lower and upper limits, which are the endpoints, unless otherwise specified. When a numerical range is described in stages, the upper and lower limits of each numerical range can be combined arbitrarily. Furthermore, in the present disclosure, expressions such as "at least one selected from the group consisting of XX, YY, and ZZ" mean any of XX, YY, ZZ, a combination of XX and YY, a combination of XX and ZZ, a combination of YY and ZZ, or a combination of XX, YY, and ZZ. Note that when XX is a group, multiple XXs may be selected, and the same applies to YY and ZZ.

[0011] Hereinafter, embodiments of the present disclosure will be described, but the present disclosure is not limited to these embodiments, and not all of the combinations of features described in the embodiments are necessarily essential to the solutions of the present disclosure. The components described in the embodiments are merely examples, and are not intended to limit the scope of the present disclosure to only those.

[0012] By using a specific silicone-containing film on the surface of an inkjet recording head where the ejection ports are provided, a film with excellent blade wipe durability can be formed. The silicone-containing film can be used as a water-repellent and oil-repellent film. This silicone-containing film is described below.

[0013] (Alkylsiloxane resin) The silicon-containing film is etched perpendicularly to the surface in the thickness direction under the following etching conditions, and the composition is analyzed by time-of-flight secondary ion mass spectrometry ToF-SIMS. At this time, SiC3H9 + The amount of SiC3H9 at an etching time of 30 seconds + The ratio of the abundance of SiC3H9 + The ratio (sometimes called the "ratio of the two") is 0.70 or greater. (Etching conditions) C 60 + Using the above C 60 + The output is set to 40 kV, and etching is performed every 30 s.

[0014] Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) Secondary Ion Mass Spectrometry (SIMS) is a surface analysis technique that performs qualitative analysis of elements and molecules on the extreme surface (up to 2 nm) of various materials. This analysis method detects fragment ions of polymers produced by the polymerization reaction of silicone compounds. Therefore, even if the terminal of the silicone resin is not a Si(CH3)3 structure, SiC3H9 is detected during measurement. + occurs. [ka]

[0015] Therefore, the SiC3H9 +The peak intensity of SiC3H9 is mainly due to the silicone resin. + The peak intensity ratio can be used as an index representing the distribution of the silicone resin in the depth direction of the silicone-containing film.

[0016] Etching for 30 seconds under the above etching conditions results in a cutting depth of about 60 nm. + A ratio of 0.70 or greater is believed to indicate that the silicone resin is uniformly distributed over a certain range in the depth direction of the silicone-containing film, resulting in excellent blade wipe durability.

[0017] On the other hand, SiC3H9 + If the ratio is below 0.70, it means that the silicone resin is segregated on the surface of the silicone-containing film and in its vicinity. This makes the silicone resin more susceptible to degradation in blade wipe tests. As a result, the liquid repellency decreases due to the degradation of the silicone resin.

[0018] SiC3H9 + The value of the ratio is preferably 0.80 or more, more preferably 0.85 or more. + The value of the ratio is, for example, 0.70 to 1.00, preferably 0.80 to 0.98, and more preferably 0.85 to 0.97.

[0019] SiC3H9 + The value of this ratio is affected by the structure of the silicone compound. Silicones have low surface free energy and tend to segregate at the surface (air interface). The degree of freedom of the silicone main chain changes depending on the structure of the silicone compound and the length of the silicone main chain, which affects the ease of segregation at the surface (air interface). When a silicone compound has an epoxy group at one end, the degree of freedom of the silicone main chain is high and it tends to segregate at the surface (air interface).

[0020] On the other hand, when the silicone compound has epoxy groups at both ends, the degree of freedom of the silicone is low, and it is thought that the siloxane main chain is less likely to segregate on the surface. Therefore, the silicone main chain tends to be fixed and the silicone tends to be distributed uniformly in the film. Therefore, SiC3H9 + From the viewpoint of making the value of the ratio 0.70 or more, it is preferable to use a material having epoxy groups at both ends of a silicone compound.

[0021] It is also effective to use an epoxy resin in the resin composition used to form the silicone-containing film. For example, even if the silicone compound has an epoxy group on its side chain, by using an epoxy resin, the silicone compound will bond strongly to the epoxy resin through a reaction with the epoxy resin. This reduces the degree of freedom of the silicone, making it difficult for the siloxane main chain to segregate on the surface, and SiC3H9 + It is thought that the ratio is likely to be 0.70 or more. From the viewpoint of forming a strong bond, it is preferable to use an alicyclic epoxy resin as the epoxy resin. On the other hand, even if a silicone compound has epoxy groups at both ends, if a material that does not bond firmly is used, the silicone compound may segregate on the surface.

[0022] The silicone-containing film is preferably a cured product of a resin composition containing a silicone compound. The resin composition is, for example, a photosensitive resin composition. The silicone compound is preferably an alkylsiloxane resin having a structure represented by the following formula (1): [ka]

[0023] (In formula (1), R5 and R6 each independently represent an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, At least two of R7, R8, X3, and X4 are each independently an epoxy-containing group, and the others are each independently an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and n+m is an integer of 1 to 60. The arrangement of the parenthesized structure with m and the parenthesized structure with n may be random or block.

[0024] The epoxy-containing group may be a group having a glycidyl ether group or a group having an alicyclic epoxy group, and the epoxy-containing group is preferably a group having a glycidyl ether group or a group having an epoxycyclohexyl group. The epoxy-containing group is more preferably a glycidoxyalkyl group having an alkyl chain of 1 to 4 carbon atoms (preferably 2 to 4) or an epoxycyclohexylalkyl group having an alkyl chain of 1 to 8 carbon atoms (preferably 2 to 6).The epoxy-containing group is even more preferably a 3-glycidoxyalkyl group having an alkyl chain of 1 to 4 carbon atoms (preferably 2 to 4) or a 2-(3,4-epoxycyclohexyl)alkyl group having an alkyl chain of 1 to 8 carbon atoms (preferably 2 to 6).

[0025] More preferred examples of the epoxy-containing group include a 3-glycidoxypropyl group, a 2-(3,4-epoxycyclohexyl)ethyl group, and a 2-(3,4-epoxycyclohexyl)pentyl group. An even more preferred example of the epoxy-containing group is a 2-(3,4-epoxycyclohexyl)ethyl group. In particular, epoxycyclohexylalkyl groups have excellent reactivity and can provide high liquid repellency.

[0026] As the alkyl group having 1 to 12 carbon atoms in formula (1), an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group, is particularly preferred. From the viewpoint of compatibility with the resin and film strength, a phenyl group or the like may be present as an aryl group having 6 to 12 carbon atoms in formula (1). In addition, in formula (1), it is preferable that two of R7, R8, X3, and X4 are epoxy-containing groups. It is preferable that X3 and X4 are epoxy-containing groups, and R7 and R8 are each independently an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms.

[0027] In formula (1), m+n is 1 to 60, preferably 10 to 60, from the viewpoint of compatibility with resins and solubility in solvents. From the viewpoint of liquid repellency, m+n is more preferably 30 to 60. m+n may be 20 to 60, or may be 25 to 45. In formula (1), m is preferably 0 or 1. The arrangement of the parenthesized structure with m and the parenthesized structure with n may be random or block. The arrangement of the parenthesized structure with m and the parenthesized structure with n is preferably random.

[0028] In this disclosure, the above SiC3H9 + By adjusting the value of the ratio, it becomes possible to distribute the silicone compound uniformly in the depth direction, and high durability is exhibited during printing. In addition, a silane coupling agent may be added to the silicone compound in order to improve adhesion to an underlying film such as an inorganic film. The silicone-containing film may be, for example, a laminate having a silicone-containing film (a layer containing silicone) on a substrate. In this case, the etching may be performed from the surface of the silicone-containing film toward the substrate.

[0029] Furthermore, the contact angle at the outermost surface of the silicone-containing film is 80° or greater. Preferably, the contact angle is 85° or greater. A contact angle of 80° or greater indicates good water repellency. The contact angle at the outermost surface of the silicone-containing film is the dynamic receding contact angle θγ of the outermost surface of the silicone-containing film with pure water, measured using a microcontact angle meter (manufactured by Microjet Corporation, "DropMeasure" (trade name)). The contact angle on the outermost surface of the silicone-containing film is, for example, 80 to 99°, preferably 85 to 98°, and more preferably 87 to 97°.

[0030] The thickness of the silicone-containing film is not particularly limited as long as it can withstand cutting by etching for 30 seconds, and good water repellency and blade wipe resistance are obtained. The thickness of the silicone-containing film is, for example, 0.1 to 100 μm, preferably 0.1 to 10 μm, and more preferably 0.2 to 2.0 μm.

[0031] (epoxy resin) The silicone-containing film preferably contains an epoxy resin. The silicone-containing film may be a cured product of a resin composition containing an epoxy resin and a silicone compound. The silicone-containing film contains, for example, an epoxy resin as a binder.

[0032] The epoxy resin is preferably a cationic polymerization type epoxy resin, and can be selected in consideration of the adhesion performance, mechanical strength, and swelling resistance of the cured product of the resin composition. The epoxy resin is, for example, a resin different from the alkylsiloxane resin having the structure represented by the above formula (1).

[0033] The epoxy resin is preferably at least one selected from the group consisting of epoxy resins having an alicyclic skeleton, epoxy resins having a bisphenol skeleton, epoxy resins having a phenol novolac skeleton, epoxy resins having a cresol novolac skeleton, epoxy resins having a norbornene skeleton, epoxy resins having a terpene skeleton, epoxy resins having a dicyclopentadiene skeleton, and epoxy resins having an oxycyclohexane skeleton.

[0034] More specifically, examples of the epoxy resins include cationically polymerizable epoxy resins such as epoxy resins having an alicyclic skeleton such as a cyclohexane skeleton, epoxy resins having a bisphenol skeleton such as bisphenol A-type and F-type epoxy resins, epoxy resins having a phenol novolac skeleton such as phenol novolac-type epoxy resins, epoxy resins having a cresol novolac skeleton such as cresol novolac-type epoxy resins, epoxy resins having a norbornene skeleton, epoxy resins having a terpene skeleton, epoxy resins having a dicyclopentadiene skeleton, and polyfunctional epoxy resins such as epoxy resins having an oxycyclohexane skeleton. One or a combination of two or more of these can be used.

[0035] It is more preferable that the epoxy resin contains an alicyclic epoxy resin. Alicyclic epoxy resins have good reactivity with cationic catalysts and can increase the crosslink density of the cured product compared to other epoxy resins. It is also preferable that the epoxy resin does not contain a benzene ring. Furthermore, the epoxy equivalent of the epoxy resin is preferably 300 g / eq or less. The epoxy equivalent is preferably 100 to 300 g / eq, more preferably 100 to 230 g / eq, and even more preferably 100 to 200 g / eq. In another preferred embodiment, the epoxy equivalent is 160 to 230 g / eq. When the epoxy equivalent is 300 or less, the reactivity with silicone compounds is excellent, resulting in superior wipe durability. The epoxy equivalent is defined as (molecular weight of epoxy resin / number of epoxy groups in one molecule of epoxy resin).

[0036] By using an epoxy resin having two or more epoxy groups, the cured product can be three-dimensionally crosslinked, and the desired curing properties can be obtained. It is more preferable to use an epoxy resin having three or more epoxy groups. Furthermore, at least one bifunctional epoxy resin may be added to a trifunctional or higher functional epoxy resin.

[0037] Commercially available trifunctional or higher epoxy resins include "jER157S70" and "jER1031S" (trade names) manufactured by Mitsubishi Chemical Corporation, "Epiclon N-695" and "Epiclon N-865" (trade names) manufactured by Dainippon Ink and Chemicals, Inc., "Celloxide 2021," "GT-300 series," "GT-400 series," and "EHPE3150" (trade names) manufactured by Daicel Corporation, "SU8" (trade name) manufactured by Nippon Kayaku Co., Ltd., "VG3101" (trade name) and "EPOX-MKR1710" (trade name) manufactured by Printec Co., Ltd., and "Denacol series" manufactured by Nagase ChemteX Corporation.

[0038] Examples of commercially available bifunctional epoxy resins include "jER1004," "jER1007," "jER1009," "jER1010," and "jER1256" (trade names) manufactured by Mitsubishi Chemical Corporation, and "EPICLON 4050" and "EPICLON 7050" (trade names) manufactured by Dainippon Ink and Chemicals, Inc.

[0039] From the viewpoint of achieving a SiC3H9 ratio of 0.70 or more, it is preferable to use a resin such as EHPE3150 that does not have a structure in which epoxy groups are directly introduced into the alicyclic skeleton, thereby reducing the influence of steric hindrance.

[0040] In a resin composition containing an epoxy resin capable of forming a silicone-containing film and a silicone compound (preferably an alkylsiloxane resin having a structure represented by formula (1)), the content of the silicone compound relative to 100 parts by mass of the epoxy resin is, for example, 0.1 to 10.0 parts by mass, 0.2 to 5.0 parts by mass, 0.3 to 2.0 parts by mass, or 0.5 to 1.5 parts by mass.

[0041] (curing accelerator) The resin composition may contain a phenolic compound or a polyol having at least two hydroxyl groups as a curing accelerator, which is effective in accelerating the cationic polymerization reaction of the epoxy resin.

[0042] Specific examples of the phenolic compounds include cardanol, terpene diphenols, and their derivatives. For example, cardanol compounds such as cardanol and cardanol derivatives are available. Examples of cardanol derivatives include derivatives in which the -OH of cardanol is epoxy-modified. Commercially available products include "Cardolite NX-2026" and "Cardolite NC-510" manufactured by Cardolite. Examples include "Cardolite LITE2020" and "Cardolite Ultra LITE 513".

[0043] If the polyol has one hydroxyl group, the effect of promoting the cationic polymerization reaction of the epoxy resin is small, so two or more hydroxyl groups are preferred. Furthermore, from the viewpoints of solubility in resins and solvents and reactivity, the polyol preferably has a number-average molecular weight of 3,000 or less. Furthermore, in order to avoid disappearance during the heating process, it is preferred that the polyol have a number-average molecular weight of 200 or more or a boiling point of 200°C or higher. The number-average molecular weight can be calculated in terms of polystyrene by a known method using gel permeation chromatography (e.g., manufactured by Shimadzu Corporation).

[0044] Specific examples of polyols include polyethylene glycols (200, 300, 400, 600, 1000, 2000) commercially available from various companies. In addition, examples of polyether polyols include the "ADEKA Polyether P Series," "BPX Series," "G Series," "SP Series," "SC Series," "CM Series," "AM Series," "EM Series," "BM Series," "PR Series," and "GR Series" (all trade names) manufactured by ADEKA.

[0045] The polyol may be a low-molecular-weight polyhydric alcohol. Examples of low-molecular-weight polyhydric alcohols include 1,2- or 1,6-hexanediol, glycerin, trimethylolpropane, 3-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2,6-hexanetriol, 1,5-dihydroxypentan-3-one, 6-hydroxycaproic acid, and 2-hydroxymethyl-1,3-propanediol. At least one of these may be used.

[0046] (Coating solvent) When the resin composition is applied as a solution, it is preferable to use a polar organic solvent as the application solvent from the viewpoint of solubility. Specific examples of polar solvents include alcohols, ketones, esters such as ethyl acetate, butyl acetate, and PGMEA (propylene glycol monomethyl ether acetate), ethers such as diglyme, tetrahydrofuran, and PGME, and glycols such as diethylene glycol. Examples of alcohols include methanol, ethanol, propanol, isopropanol, and butanol, and examples of ketones include methyl ethyl ketone and methyl isobutyl ketone.

[0047] (Photopolymerization initiator) The resin composition may be a photosensitive resin composition containing a photopolymerization initiator. When the photosensitive resin composition is applied to a substrate and cured, the photopolymerization initiator allows the photosensitive resin composition to be cured by light irradiation, thereby forming a silicone-containing film that is a liquid-repellent and stain-resistant film. In this case, the liquid repellency and mechanical strength are significantly improved compared to thermal curing, and further, microfabrication by patterning is also possible. The photopolymerization initiator is preferably cationic polymerizable.

[0048] Examples of the photopolymerization initiator include sulfonic acid compounds, diazomethane compounds, sulfonium salt compounds, iodonium salt compounds, and disulfone compounds.

[0049] As the photopolymerization initiator, a cationic photopolymerization initiator capable of low-temperature curing and having high catalytic function can be suitably used. Specific examples of cationic photopolymerization initiators include ionic acid generators. The cationic moiety can be an onium ion with high absorption, such as oxonium, ammonium, phosphonium, sulfonium, and iodonium. Among these, sulfonium ions are more preferred because of their high i-line (365 nm wavelength) absorption and excellent cationic polymerization and crosslinking properties.

[0050] Specific examples of sulfonium-based cations include triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4-fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, and 4-(phenylthio)phenyl. Diphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolylsulfonium, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenyldi-p-tolylsulfonium, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium, [4-(2 -thioxanthonylthio)phenyl]diphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfonium, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2- chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium,10-Dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-(9-oxo-9H-thioxanthen-2-yl)thiophenyl-9-oxo-9H-thioxanthen-2-yl Phenylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thiaanthrene, 5-phenylthiaanthrene, 5-tolylthiaanthrene, 5-(4-ethoxyphenyl)thiaanthrene, 5-(2,4,Triarylsulfonium compounds such as (6-trimethylphenyl)thiaanthrenenium; diarylsulfonium compounds such as diphenylphenacylsulfonium, diphenyl 4-nitrophenacylsulfonium, diphenylbenzylsulfonium, and diphenylmethylsulfonium; phenylmethylbenzylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 4-methoxyphenylmethylbenzylsulfonium, 4-acetocarbonyloxyphenylmethylbenzylsulfonium, 4-hydroxyphenylmethyl-1-naphthylmethylsulfonium, 4-hydroxyphenyl(2-naphthylmethyl)methylsulfonium, and 2-naphthylmethylbenzylsulfonium Monoarylsulfonium compounds such as 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, phenylmethylphenacylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, 4-methoxyphenylmethylphenacylsulfonium, 4-acetocarbonyloxyphenylmethylphenacylsulfonium, 2-naphthylmethylphenacylsulfonium, 2-naphthyloctadecylphenacylsulfonium, and 9-anthracenylmethylphenacylsulfonium; dimethylphenacylsulfonium, phenacyltrhydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium, and octadecylmethylphenacylsulfonium. and trialkylsulfonium such as sulphonium.

[0051] The molar absorption coefficient of the photopolymerization initiator at a wavelength of 365 nm is 400 M -1 cm -1 The molar extinction coefficient is preferably 400M or more. -1 cm -1 By satisfying the above conditions, the crosslinking density does not decrease during the curing reaction, and water repellency and photopatternability can be imparted.

[0052] The molar absorption coefficient of a compound such as a photopolymerization initiator is measured as follows: The target compound is dissolved in a solvent that has no absorption at 365 nm, such as acetonitrile, to form a solution, which is then placed in a quartz cell and the absorbance at 365 nm is measured using a UV-Vis-NIR spectrophotometer (manufactured by JASCO). The molar absorption coefficient can be calculated from the obtained absorbance using the following formula: Molar extinction coefficient = absorbance ÷ molar concentration of compound ÷ light path of cell

[0053] The anion moiety can be selected from borate, phosphorus, antimony, and gallate anions, which have high acid strength, and is preferably at least one selected from the group consisting of gallate anions and borate anions. Among these, tetrakis(pentafluorophenyl)borate ion, trifluorotris(pentafluoroethyl)phosphate ion, hexafluoroantimonate ion, and tetrakis(pentafluorophenyl)gallate ion, which have excellent cationic polymerization and crosslinking reaction properties, are more preferred. This allows for the development of water repellency and photopatternability, as is the case with the selection of cations.

[0054] Suitable photopolymerization initiators include ADEKA Corporation's "ADEKA ARCLES SP-170," "ADEKA ARCLES SP-172," and "ADEKA ARCLES SP-150" (all trade names), and Midori Chemical Co., Ltd.'s "BBI-103" and "BBI-102" (all trade names). Other examples include Sanwa Chemical's "IBPF," "IBCF," "TS-01," and "TS-91" (all trade names), and San-Apro's "CPI-410S," "CR-C1," "CPI-410B," "CPI-310B," "CPI-310FG," "ES-1B," "VC-1FG," and "CPI-101A" (all trade names). Furthermore, the composition may contain basic substances such as amines, photosensitizers such as anthracene derivatives, and silane coupling agents for the purpose of improving photolithography performance and adhesion performance.

[0055] The content of the photopolymerization initiator is not particularly limited and can be appropriately changed depending on the resin used. The amount of the photopolymerization initiator added is preferably in the range of 0.5 to 5 parts by mass, more preferably 1.0 to 4.0 parts by mass, per 100 parts by mass of the resin (preferably epoxy resin) contained in the photosensitive resin composition.

[0056] (base material) The silicone-containing film can be used as a liquid-repellent, anti-fouling film. The silicone-containing film can be used as a liquid-repellent, anti-fouling film for a liquid ejection head such as an inkjet recording head. The substrate on which the silicone-containing film is formed is, for example, a surface on which ejection ports are provided. A silicone-containing film may also be provided at a position other than the surface on which the ejection ports of the liquid ejection head are provided. The materials of the surface on which the ejection ports are provided and other components of the liquid ejection head that serve as the substrate are not particularly limited, and can be selected mainly from inorganic substrates and resin compositions.

[0057] Examples of inorganic substrates include Si, SiO2, SiOC, SiC, SiCN, Ta, TaO, and Al2O3.

[0058] The resin composition is a negative epoxy resin composition containing a multifunctional epoxy resin as the main component, specifically, bisphenol A epoxy resin, bisphenol E epoxy resin, bisphenol F epoxy resin, novolac epoxy resin, cresol novolac, etc. epoxy resins of the type, alicyclic epoxy resins, etc.

[0059] Commercially available epoxy resins include "157S70" and "jER1031S" (all trade names) manufactured by Mitsubishi Chemical Corporation, and "Epiclon N-695" and "Epiclon N-865" (all trade names) manufactured by DIC Corporation. Other examples include "Celloxide 2021," "GT-300 Series," "GT-400 Series," and "EHPE3150" (all trade names) manufactured by Daicel Corporation, and "SU8" (trade name) manufactured by Nippon Kayaku Co., Ltd. Further examples include "VG3101" and "EPOX-MKR1710" (trade names) manufactured by Printec Co., Ltd., and "Denacol Series" (trade names) manufactured by Nagase ChemteX Corporation.

[0060] As an example of the application of the silicone-containing film, a method for manufacturing an inkjet recording head using the silicone-containing film as a liquid-repellent and stain-resistant film will be described below with reference to the drawings. However, the scope of application of the silicone-containing film according to the present disclosure is not limited thereto.

[0061] <Method of manufacturing a recording head> (Recording head using a resin composition as a substrate) Fig. 1A is a schematic diagram showing an example of an inkjet recording head, and Fig. 1B is a cross-sectional view of the recording head taken along a line AB in Fig. 1A and perpendicular to a substrate 1.

[0062] 1A and 1B has a substrate 1 on which energy generating elements 2 that generate energy used to eject liquid are arranged in two rows at a predetermined pitch. A liquid supply port 3 is opened in the substrate 1 between the two rows of the energy generating elements 2. On the substrate 1, ejection ports 5 are formed by an ejection port forming member 4 at positions facing each of the energy generating elements 2.

[0063] The shape of the discharge port 5 may be a so-called tapered shape in which the area of ​​the cross section parallel to the substrate 1 decreases from the substrate 1 side toward the discharge port 5. The discharge port forming member 4 is composed of a side wall 8 that forms individual flow paths 6 that communicate from the supply port 3 to each discharge port 5, and a top plate 9 on which the discharge ports 5 open. The discharge port forming member 4 may have the side wall 8 and the top plate 9 integrated together.

[0064] A liquid-repellent, anti-fouling film (liquid-repellent layer) 7 is provided on the ejection port forming member. For example, an inkjet recording head has a silicone-containing film (liquid-repellent, anti-fouling film 7) on the surface where the ejection ports are provided. The liquid-repellent, anti-fouling film 7 prevents ink ejected from the ejection ports 5 from adhering to the surface of the recording head. The shape, material, etc. of the substrate 1 are not particularly limited as long as it functions as part of the members that make up the flow path 6 and can also function as a support for the ejection port forming member 4. In this embodiment, a silicon substrate is used as the substrate 1 because it is easy to process.

[0065] This recording head is arranged so that the surface where the ejection ports 5 open faces the recording surface of the recording medium. Energy generated by the energy generating elements 2 is applied to ink filled in the flow paths 6 via the supply ports 3, causing ink droplets to be ejected from the ejection ports 5 and attached to the recording medium, thereby performing recording. The energy generating elements 2 can be elements that generate energy by heat, such as electrothermal conversion elements (so-called heaters), or elements that generate energy mechanically, such as piezoelectric elements.

[0066] The liquid-repellent, antifouling film 7 is a cured product of a resin composition. Specifically, the liquid-repellent, antifouling film 7 can be formed as a cured product by applying a solution containing the resin composition and curing the coating of the solution.

[0067] 2A to 2H, an example of a method for manufacturing an inkjet recording head will be described. In the inkjet recording head, known materials can be used except for the liquid-repellent and stain-proofing film 7.

[0068] 2A to 2H are schematic cross-sectional views showing an example of a method for manufacturing an inkjet recording head according to the steps, and the positions of the cross sections are the same as those in FIG. 1B.

[0069] First, as shown in Fig. 2A, a substrate 1 having energy generating elements 2 provided on its surface is prepared. Electrodes (not shown) for inputting control signals to operate the energy generating elements 2 are connected to the energy generating elements 2. Various functional layers may also be provided, such as a protective layer (not shown) for improving the durability of the energy generating elements 2 and an adhesion improving layer (not shown) for improving adhesion between the ejection port forming member 4 and the substrate 1.

[0070] 2B, an ink supply port 3 is formed penetrating the substrate 1. The supply port 3 can be formed by wet etching using an alkaline etching solution such as TMAH (tetramethylammonium hydroxide), or by dry etching such as reactive ion etching.

[0071] Next, as shown in FIG. 2C, a first photosensitive resin layer 10 containing a photosensitive resin and a photopolymerization initiator is formed on the substrate 1 including the energy generating elements 2. The first photosensitive resin layer 10 is a so-called negative photosensitive resin layer. The first photosensitive resin layer 10 is preferably formed by applying a photosensitive resin to a film substrate made of PET or polyimide and transferring it onto the substrate 1 using a lamination method. Epoxy resin is preferably used as the photosensitive resin contained in the first photosensitive resin layer 10 because it satisfies various performance requirements, such as high mechanical strength, adhesion to the substrate, ink resistance, and resolution for patterning the fine pattern of the ejection orifices 5.

[0072] The epoxy resin and photopolymerization initiator may be the same as those described above. The amount of photopolymerization initiator added can be any amount that achieves the target sensitivity. The amount of photopolymerization initiator added is preferably in the range of 0.5 to 5% by mass relative to the epoxy resin. Furthermore, a wavelength sensitizer may be added as needed. Examples of such wavelength sensitizers include "SP-100" (trade name) manufactured by Adeka Corporation, and "UVS-1101," "UVS-1331," and "UVS-2171" (all trade names) manufactured by Air Water Performance Chemicals Inc.

[0073] Furthermore, additives can be added to the photosensitive resin as needed, such as a flexibility-imparting agent to reduce the elastic modulus of the epoxy resin, or a silane coupling agent to improve adhesion to the substrate.

[0074] Next, as shown in FIG. 2D, pattern exposure is performed through a mask (not shown), followed by heat treatment to form side walls 8. The mask is 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 chromium film is formed in accordance with the pattern of the flow channel 6. As the exposure device, a single-wavelength light source such as an i-line exposure stepper or KrF stepper, or a projection exposure device having a broad-wavelength light source of a mercury lamp such as Canon's "Mask Aligner MPA-600Super" (product name) can be used.

[0075] As shown in FIG. 2E, a second photosensitive resin layer 11 is formed on the substrate 1 on which the sidewalls 8 have been formed in this manner. The second photosensitive resin layer 11 is a negative photosensitive resin layer similar to the first photosensitive resin layer 10. As the photosensitive resin contained in the second photosensitive resin layer 11, a bisphenol type epoxy resin or a novolac type epoxy resin is preferably used. The resin layer 11 can be formed in the same manner as the first photosensitive resin layer 10.

[0076] 2F, a coating film 12 of a solution of a photosensitive resin composition for forming the liquid-repellent and stain-resistant film 7 is formed on the second photosensitive resin layer 11. The coating film 12 can be formed by applying the resin composition by a method such as spin coating, roll coating, or slit coating.

[0077] Next, as shown in FIG. 2G, pattern exposure is performed through a mask (not shown) and the coating is cured to form a top plate 9 and a liquid-repellent, stain-resistant coating 7. The mask is 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 discharge ports 5. As the exposure device, a single-wavelength light source such as an i-line exposure stepper or KrF stepper, or a projection exposure device having a broad-wavelength mercury lamp as a light source such as Canon's "Mask Aligner MPA-600Super" (product name) can be used.

[0078] Next, as shown in FIG. 2H, the unexposed portions of the second photosensitive resin layer 11 and the coating film 12 are removed by a development process to form the discharge ports 5. By simultaneously exposing and developing the second photosensitive resin layer 11 and the coating film 12, the cationic polymerizable groups in the second photosensitive resin layer 11 and the coating film 12 react with each other, resulting in a highly durable, highly antistatic, liquid-repellent, and stain-resistant film 7. At this time, the unexposed portions of the first photosensitive resin layer 10 are also dissolved and removed at the same time, forming the flow paths 6.

[0079] Furthermore, if necessary, a heat treatment is carried out, and then bonding of members (not shown) for ink supply and electrical bonding (not shown) for driving the energy generating elements 2 are carried out to complete the inkjet recording head.

[0080] <Recording method> The recording method according to the embodiment of the present disclosure uses the inkjet recording head to record an image on a recording medium by ejecting a liquid, particularly an ink containing a pigment, from the inkjet recording head. When the inkjet recording head is filled with ink, the side surface of the liquid-repellent and stain-resistant film is always in contact with the ink. By using the inkjet recording head, even after long-term use, non-discharge can be suppressed because the liquid-repellent and stain-resistant film 7 has ink durability.

[0081] (Inkjet recording head using inorganic substrate as base material) <Bonded substrate formation process> The inkjet recording head may use an inorganic substrate as the base material, and an example of an inkjet recording head using an inorganic substrate is shown in Figure 4A. The liquid ejection head 25 includes a flow path substrate 14, an actuator substrate 15, and a nozzle substrate 16, which are bonded together via an adhesive 17. The actuator substrate 15 has a piezoelectric element 18 disposed on its surface. For example, a PZT (lead zirconate titanate) film formed by a sol-gel method or a sputtering method can be used as the piezoelectric element 18. Such a piezoelectric element 18 is made of a sintered body of metal oxide crystal.

[0082] A flow path substrate 14 made of silicon is disposed so as to cover the piezoelectric elements 18, and is bonded to the surface of the actuator substrate 15 via an adhesive 17. A nozzle substrate 16 is bonded to the back surface of the actuator substrate 15 via the adhesive 17. An ink tank (not shown) is disposed on the flow path substrate 14, and a liquid flow path section 19 is formed so as to penetrate the flow path substrate 14. The liquid flow path section 19 communicates with the inside of the actuator substrate, and is connected to a liquid ejection port 20 of the nozzle substrate.

[0083] When a drive voltage is applied to the piezoelectric element 18 from a drive IC (not shown), the piezoelectric element 18 is deformed by the inverse piezoelectric effect. Applying a drive voltage with a pull-push-pull waveform causes the cavity to expand and contract, resulting in a volume change, and when the liquid in the liquid flow path is pressurized, a meniscus is formed on the surface of the liquid ejection port 20. The pressurized liquid then contracts, causing it to be ejected from the liquid ejection port 20 in the form of droplets.

[0084] The inkjet recording head has a water-repellent film 21 on the surface where the liquid ejection orifices 20 are provided. The water-repellent film 21 may be a liquid-repellent and stain-resistant film, and the above-mentioned silicone-containing film can be used. However, if the inside of the nozzle of the liquid ejection orifice 20 is water-repellent, a meniscus will be formed deep inside the nozzle, which may cause instability in the ejection volume and ejection direction. Therefore, it is preferable to form the water-repellent film 21 by the following means. In Figures 4A and 4B, the area surrounding the liquid ejection orifice 20 is referred to as area A. Figures 5A to 5D explain area A in an enlarged manner.

[0085] <Method for forming water-repellent film> 1 shows a method for forming a water-repellent film on a liquid ejection head. The formation of the water-repellent film is performed on the substrates bonded with adhesive. (1) a water-repellent film forming step of forming a water-repellent film on the surface of the nozzle substrate and inside the nozzle; (2) a surface protection step of forming a protective member on the water-repellent film on the surface of the nozzle substrate; (3) a plasma treatment step of making the water-repellent film inside the nozzle hydrophilic by plasma treatment; (4) a protective member peeling step of peeling off the protective member. Each step will be described in detail below.

[0086] (1) Water-repellent film formation process A water-repellent film made of a silicone compound is formed on a nozzle substrate in which a plurality of ejection ports are formed. FIG. 5A is an enlarged view of the ejection port 20 portion of region A. It is preferable to use a nozzle substrate 16 in which a flow path substrate 14 and an actuator substrate 15 are bonded. Before forming the water-repellent film, the surface of the nozzle substrate may be cleaned. For example, plasma treatment, ion beam cleaning, UV ozone cleaning, etc. can be used.

[0087] The water-repellent film 21 can be formed by a physical vapor deposition method such as vapor deposition. In vapor deposition, the substrate is placed in a vacuum chamber and a water-repellent material is vaporized in the vacuum chamber. Alternatively, the water-repellent film 21 can be formed by a liquid phase method such as roller coating, dipping, or spin coating.

[0088] 5A, a water-repellent film 21 is formed on the surface where the discharge port 20 is provided. Here, since the discharge port 20 is formed in the nozzle substrate 16, the water-repellent film 22 is also formed inside the discharge port 20. Therefore, the water-repellent film 21 on the surface of the nozzle substrate is left, and the water-repellent film 22 on the side wall of the discharge port inside the nozzle is made hydrophilic.

[0089] (2) Protective member forming process Next, as shown in FIG. 5B, a protective member 23 is formed on the area where the water-repellent film 21 is to be left. There are no particular restrictions on the protective member 23, and resin materials, tape, and the like can be selected as appropriate. If the protective member around the ejection port floats, the water-repellent film on the surface will be hydrophilized by subsequent plasma treatment. In this case, the meniscus at the ejection port will become unstable, resulting in ejection failure. Therefore, to prevent the protective tape from floating, it is possible to apply the protective tape under reduced pressure.

[0090] (3) Plasma treatment process Next, as shown in FIG. 5C, the water-repellent film 22 on the ejection port side wall is made hydrophilic by performing plasma treatment from the flow path substrate side, thereby forming a hydrophilic water-repellent film 24.

[0091] As an example of a plasma processing method, a nozzle substrate is placed in a vacuum pressure chamber and oxygen plasma is generated. The plasma travels from the flow path forming substrate through the actuator substrate 16 to the discharge port, as shown in Figure 5C. Devices such as microwaves and remote plasma can be used for the plasma depending on the purpose. Because the plasma travels through a curved flow path, it is preferable to eliminate substrate bias and use conditions that do not rely on ion assistance. This allows for isotropic radical movement, primarily through radical reaction. The lower limit of the processing temperature should be determined taking throughput into consideration, as it is related to the processing speed, while the upper limit should be determined from the heat resistance of the protective tape used.

[0092] (4) Protective film peeling process 5D, the protective member 23 is peeled off from the nozzle substrate to complete the liquid ejection head. Since the inside of the nozzle of the liquid ejection head obtained in this manner is hydrophilic, the ejection volume and ejection direction are stable. [Example]

[0093] The present disclosure will be described in further detail below with reference to examples, but the present disclosure is not limited to the following examples.

[0094] Example 1 (Preparation of liquid-repellent and stain-resistant film on substrate) A liquid-repellent and stain-resistant film was formed according to the procedures shown in Figures 3A and 3B. A photosensitive resin composition having the formulation of Example 1 shown in Table 4 was applied to a silicon substrate 13 to form a coating film 12, which was then heat-treated at 70°C for 3 minutes. Subsequently, the coating film 12 was exposed to 5000 Jm using an i-line exposure stepper (Canon Inc.'s "FPA-3000i5+"). -2 The film was exposed to light at 1000 K and then heat-treated at 90°C for 5 minutes. After washing with PGMEA, the film was further heat-treated at 200°C for 1 hour to form a liquid-repellent and stain-resistant film 7. The thickness of the silicone-containing liquid-repellent and stain-resistant film was adjusted to 0.5 µm. In Tables 4 and 5, the initiators and solvents used were as follows. Photopolymerization initiator: CPI-410S, CPI-410B, CPI-310FG (all manufactured by San-Apro) Solvent: PGMEA

[0095] (Fabrication of Ink Jet Recording Head) In addition to the liquid-repellent and stain-proofing film, an inkjet recording head was also fabricated by the steps shown in FIGS. 2A to 2H. First, as shown in FIG. 2A, a substrate 1 having an energy generating element 2 provided on its surface was prepared, and an ink supply port 3 penetrating the substrate 1 was formed by etching using TMAH as shown in FIG. 2B.

[0096] Next, as shown in FIG. 2C, a cationic polymerizable resin composition shown in Table 1 was transferred onto the substrate 1 including the energy generating elements 2 by lamination to form a first photosensitive resin layer 10. Furthermore, as shown in FIG. 2D, pattern exposure was performed through a quartz mask (not shown), and side walls 8 were formed by heat treatment at 90°C for 5 minutes. An i-line exposure stepper (Canon Inc.'s "FPA-3000i5+") was used as the exposure device, and the exposure dose was 10,000 Jm. -2 It was decided.

[0097] On the substrate 1 on which the sidewalls 8 were thus formed, a second photosensitive resin layer 11 was formed as shown in Fig. 2E. The second photosensitive resin layer 11 was formed by transferring the cationic polymerizable resin composition shown in Table 2 by a lamination method. Next, as shown in FIG. 2F, the photosensitive resin composition having the formulation of Example 1 shown in Table 4 was applied onto the second photosensitive resin layer 11 and heat-treated at 70° C. for 3 minutes. The second photosensitive resin layer 11 and the coating film 12 were simultaneously subjected to pattern exposure through a mask (not shown) and then heat-treated at 90°C for 5 minutes. An i-line exposure stepper (Canon Inc.'s "FPA-3000i5+") was used as the exposure device, and the exposure dose was 5000 Jm. -2 (Figure 2G). Finally, the non-exposed areas of the photosensitive resin layer and coating were dissolved and removed using PGMEA, and the resulting product was heat-treated at 200°C for 1 hour to form an ejection port 5, a flow path 6, and a liquid-repellent and antifouling film 7 (Figure 2H). The thickness of the liquid-repellent and stain-resistant silicone-containing film was set to 0.5 μm.

[0098] [Table 1]

[0099] [Table 2]

[0100] (Examples 2 to 43) In forming the liquid-repellent and stain-resistant film 7, a liquid-repellent and stain-resistant film on a substrate and an inkjet recording head were produced in the same manner as in Example 1, except that the resin compositions of Examples 2 to 43 shown in Tables 4-1 and 4-2 were used.

[0101] (Comparative Examples 1 to 42) A liquid-repellent antifouling film on a substrate and an inkjet recording head were produced in the same manner as in Example 1, except that the resin compositions of Comparative Examples 1 to 42 shown in Table 5 were used in forming the liquid-repellent antifouling film 7.

[0102] The silicone compounds, epoxy resins and initiators used in the compositions of the Examples and Comparative Examples in Tables 4-1, 4-2 and 5 are as follows: Examples 1 to 43 and Comparative Examples 1 to 42 are examples in which a silicone compound having the structure represented by formula (1) was used. The epoxy-containing group of the silicone compound has a glycidyl ether group or an epoxycyclohexyl group. 1, 4, 5, 7, 8, 10, 11, 12, 15, 18, 19, 21, 22, 24, 25, 26, 27, 30, 31, 32, 35, 36, 39, 40, 43, and Comparative Examples 1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, and 42. In Examples 2, 3, 6, 9, 13, 14, 16, 17, 20, 23, 28, 29, 33, 34, 37, 38, 41, and 42, and Comparative Examples 2, 22, and 23, the epoxy-containing group of the silicone compound was a 2-(3,4-epoxycyclohexyl)ethyl group.

[0103] In Examples 1 to 43 and Comparative Examples 1 to 42, the photopolymerization initiator is cationic polymerizable.

[0104] <Evaluation of liquid-repellent and stain-resistant films> The liquid-repellent and stain-resistant films prepared in Examples 1 to 43 and Comparative Examples 1 to 42 were evaluated as follows.

[0105] (Initial water repellency and wipe durability) The dynamic receding contact angle θγ of the liquid-repellent and antifouling film with pure water was measured using a microcontact angle meter (Microjet Corporation, "DropMeasure" (trade name)) to evaluate the initial water repellency. The initial water repellency value was taken as the contact angle on the outermost surface of the silicone-containing film. The liquid-repellent and stain-resistant film was wiped using a pigment ink under the conditions shown in Table 3. The θγ values ​​were then measured in the same manner as above to evaluate the mechanical strength. The wipe durability was evaluated based on the initial water repellency of 1.00.

[0106] [Table 3]

[0107] (Evaluation of inkjet recording heads) The ink jet recording heads produced in Examples 1 to 43 and Comparative Examples 1 to 42 were evaluated as follows. Using a Canon printer MB5330, a continuous printing test was conducted in an environment of 30°C and 80% RH, and the presence or absence of dot distortion was visually confirmed. The continuous printing test consisted of printing 100 sheets of A4 solid print in succession. If distortion occurred in even one place within the A4 print, the print quality was deemed NG.

[0108] (Elemental analysis in the depth direction) The silicone-containing films, which are liquid-repellent and stain-resistant films obtained in Examples 1 to 43 and Comparative Examples 1 to 42, were subjected to elemental analysis by ToF-SIMS while etching under the following etching and analysis conditions. + The ratio of abundance of each of the two compounds was obtained. The results are shown in Tables 4 and 5.

[0109] The etching conditions and analysis conditions are as follows. Measurement device: nanoTOF II (product name, manufactured by ULVAC-PHI, Inc.) Primary ion species: Au1 + Acceleration voltage: 30 kV Primary ion current: 3.5μA Repetition rate: 8.2kHz Raster mode: Bunched Raster size: 100μm x 100μm Measurement mode: Positive Neutralization electron gun: used Measurement time: 120 seconds Sample preparation: Using the liquid-repellent and antifouling film on the substrate Sample pretreatment: None Using ULVAC-PHI's standard software (WincandenceN), the evaluation was performed based on the mass numbers of the Si ions and fragment ions originating from the resin or silane compound. The ion intensity originating from the silicon fragment ion (m / z 73) with mass number 73 was confirmed, and the SiC3H9 + The abundance was determined as

[0110] In addition, after sputtering the silicon-containing film under the following conditions, elemental analysis was performed by ToF-SIMS under the same conditions as above to confirm the ion intensity derived from the fragment ion (m / z 73) of silicon with a mass number of 73. SiC3H9 + The abundance was determined as The sputtering conditions were as follows: Sputter type: C 60 + Accelerating voltage: 40 kV Current: 6.5nA Raster size: 800 x 800 μm Irradiation time: 30sec / cycle Sputtering time: 600 seconds In addition, when we confirmed the cutting depth by sputtering an SiO2 film under the same conditions in advance, we confirmed that it could remove 5 nm in 60 seconds.

[0111] In addition, Figure 6 shows the composition of the silicon-containing film when etching is performed in the thickness direction perpendicular to the surface of the silicon-containing film under the above etching conditions and a composition analysis is performed by time-of-flight secondary ion mass spectrometry ToF-SIMS. + The amount of SiC3H9 + 1 shows the change in abundance of . The ions derived from the silicone-containing film are SiC3H9 + The ions originating from the underlying organic resin film are C7H7. SiC3H9 + The amount of silicon compound present on the surface was reduced by approximately 0.9 after an etching time of 30 seconds, assuming that the amount present on the surface was 1, and it was confirmed that the silicon compound was present uniformly inside the film.

[0112] [Table 4]

[0113] [Table 5]

[0114] In the table, "parts" refers to parts by mass. The unit of epoxy equivalent is g / eq. The type of initiator indicates the type of anion. The initial water repellency value indicates the contact angle (°) on the outermost surface of the silicone-containing film. The wipe test values ​​are the water repellency values ​​after the wipe test, with the dynamic receding contact angle θγ taken as 1.00. Silicone compounds with product names beginning with X-22 are manufactured by Shin-Etsu Chemical Co., Ltd. The DOWSIL series is manufactured by Dow-Toray Industries, Inc. EHPE 3150 and the CELLOXIDE series are manufactured by Daicel Corporation 157S70 and the jER series are manufactured by Mitsubishi Chemical Corporation Epiclon series is manufactured by Dainippon Ink and Chemicals, Inc. ACRYDIC A-418 and BURNOCK PH 2891 are manufactured by DIC Corporation.

[0115] Regarding epoxy silicone: The double-ended alicyclic silicone compound has alicyclic epoxy-containing groups at both ends of the silicone main chain. The silicone compound does not have an epoxy-containing group on the side chain. The "double-ended" silicone compound has an epoxy-containing group (not an alicyclic epoxy) at both ends of the silicone main chain, but the silicone compound does not have an epoxy-containing group on the side chain. The "side chain" silicone compound has an epoxy-containing group (not an alicyclic epoxy) on the side chain of the silicone main chain, but the silicone compound does not have an epoxy-containing group on the terminal. The side chain alicyclic is a silicone compound having an alicyclic epoxy-containing group in a side chain of the silicone main chain, and the silicone compound does not have an epoxy-containing group at the terminal. The side chain terminals are silicone compounds having epoxy-containing groups at both ends of the silicone main chain and on the side chains. The one-end silicone compound has an epoxy-containing group at one end of the silicone main chain.

[0116] As shown in Table 4, in Examples 1 to 43, a film in which silicone was distributed uniformly in the depth direction was achieved, and as a result, excellent wiping durability was exhibited. In particular, a silicone compound having epoxy-containing groups at both ends of the silicone was able to produce a film in which silicone was distributed more uniformly in the depth direction, and showed even better wiping durability. This is thought to be because the siloxane main chain is sufficiently hardened in the film due to the presence of highly reactive 3-glycidoxypropyl groups and 2-(3,4-epoxycyclohexyl)alkyl groups at the terminals.

[0117] It was found that epoxy resins with a smaller epoxy equivalent have better reactivity with silicone compounds and therefore better wipe durability. Particularly, epoxy resins with an epoxy equivalent of 300 or less showed high wipe durability. Furthermore, EHPE3150, which does not have a benzene ring, has excellent compatibility with silicone compounds, making it suitable as an epoxy resin.

[0118] On the other hand, in Comparative Examples 1 to 42, the θγ after wiping was less than 0.70, and the mechanical strength was insufficient. It was found that silicone compounds containing one epoxy group have a degree of freedom in the siloxane main chain and are prone to segregation on the film surface. Therefore, it is thought that the siloxane main chain was scraped off in the wipe durability test, resulting in poor wipe durability.

[0119] In the evaluation using an inkjet recording head, there was no distortion even in continuous printing and high print quality was achieved for Examples 1 to 43. On the other hand, distortion was observed after continuous printing for Comparative Examples 1 to 42.

[0120] As described above, fluorine-based water repellent materials exhibit good water repellency, but there are concerns about their impact on the environment. On the other hand, the photosensitive resin composition according to this embodiment exhibits good water repellency even without containing a fluorine-based water repellent material. Therefore, the technology described herein can contribute to the realization of a sustainable society, such as a decarbonized / recycling-based society.

[0121] The present disclosure relates to the following configurations. (Configuration 1) An inkjet recording head, the ink jet recording head has a silicone-containing film on a surface where the ejection ports are provided, An acceleration voltage of 40 kV was applied to the silicon-containing film in the thickness direction perpendicular to the surface. + When the surface of the silicon-containing film etched using the etching method was subjected to composition analysis by time-of-flight secondary ion mass spectrometry ToF-SIMS, the SiC3H9 + The amount of SiC3H9 at an etching time of 30 seconds + The ratio of abundances of is 0.70 or more, The ink jet recording head is characterized in that the contact angle on the outermost surface of the silicone-containing film is 80° or more. (Configuration 2) 2. The ink jet recording head according to claim 1, wherein the contact angle is 85° or more. (Configuration 3) the silicone-containing film is a cured product of a resin composition containing a silicone compound, 3. The ink jet recording head according to claim 1, wherein the silicone compound is an alkylsiloxane resin having a structure represented by the following formula (1): TIFF2026028212000009.tif39153 (In formula (1), R5 and R6 each independently represent an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, At least two of R7, R8, X3, and X4 are each independently an epoxy-containing group, and the others are each independently an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and n+m is an integer of 1 to 60. (Configuration 4) 4. The ink jet recording head according to Configuration 3, wherein the epoxy-containing group is a group having a glycidyl ether group or a group having an epoxycyclohexyl group. (Configuration 5) 5. The ink jet recording head according to configuration 3 or 4, wherein the epoxy-containing group is a 2-(3,4-epoxycyclohexyl)ethyl group. (Configuration 6) the resin composition contains a photopolymerization initiator, 6. The ink jet recording head according to any one of Configurations 3 to 5, wherein the photopolymerization initiator is cationic polymerizable. (Configuration 7) The ink jet recording head according to any one of Configurations 3 to 6, wherein the resin composition contains an epoxy resin different from the alkylsiloxane resin having the structure represented by formula (1). (Configuration 8) 8. The inkjet recording head according to Configuration 7, wherein the epoxy resin is at least one selected from the group consisting of epoxy resins having an alicyclic skeleton, epoxy resins having a bisphenol skeleton, epoxy resins having a phenol novolac skeleton, epoxy resins having a cresol novolac skeleton, epoxy resins having a norbornene skeleton, epoxy resins having a terpene skeleton, epoxy resins having a dicyclopentadiene skeleton, and epoxy resins having an oxycyclohexane skeleton. (Configuration 9) 9. The ink jet recording head according to claim 7 or 8, wherein the epoxy resin has an epoxy equivalent of 300 g / eq. or less. (Configuration 10) 10. The ink jet recording head according to any one of Configurations 7 to 9, wherein the epoxy resin comprises an alicyclic epoxy resin. [Explanation of symbols]

[0122] 1 substrate, 2 energy generating element, 3 ink supply port, 4 ejection port forming member, 5 ejection port, 6 flow path, 7 liquid repellent layer, 8 side wall, 9 top plate, 10 first photosensitive resin layer, 11 second photosensitive resin layer, 12 coating film, 13 silicon base plate, 14 flow path substrate, 15 actuator substrate, 16 nozzle substrate, 17 adhesive, 18 energy generating element, 19 liquid flow path portion, 20 liquid ejection port, 21 water-repellent film, 22 water-repellent film on the ejection port side wall portion, 23 protective member, 24 hydrophilized water-repellent film, 25 liquid ejection head

Claims

1. An inkjet recording head, the ink jet recording head has a silicone-containing film on a surface where the ejection ports are provided, A C60 ion beam was applied at an acceleration voltage of 40 kV perpendicular to the surface of the silicone-containing film in the thickness direction. ＋ When the surface of the silicon-containing film etched using the etching method was subjected to composition analysis by time-of-flight secondary ion mass spectrometry ToF-SIMS, SiC at the outermost surface (0s) of the silicon-containing film was ３ H ９ ＋ With respect to the amount of SiC present, the amount of SiC present at an etching time of 30 seconds ３ H ９ ＋ The ratio of the abundance of The ink jet recording head is characterized in that the contact angle of the outermost surface of the silicone-containing film is 80° or more.

2. 2. The ink jet recording head according to claim 1, wherein the contact angle is 85[deg.] or more.

3. the silicone-containing film is a cured product of a resin composition containing a silicone compound, 2. The ink jet recording head according to claim 1, wherein the silicone compound is an alkylsiloxane resin having a structure represented by the following formula (1): (In formula (1), R ５ , and R ６ are each independently an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, R ７ , R ８ , X ３ , and X ４ At least two of the groups are independently an epoxy-containing group, and the others are independently an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and n+m is an integer of 1 to 60.

4. 4. The ink jet recording head according to claim 3, wherein the epoxy-containing group is a group having a glycidyl ether group or a group having an epoxycyclohexyl group.

5. 4. The ink jet recording head according to claim 3, wherein the epoxy-containing group is a 2-(3,4-epoxycyclohexyl)ethyl group.

6. the resin composition contains a photopolymerization initiator, 4. An ink jet recording head according to claim 3, wherein said photopolymerization initiator is cationic polymerizable.

7. 7. The ink jet recording head according to claim 3, wherein the resin composition contains an epoxy resin different from the alkylsiloxane resin having the structure represented by formula (1).

8. 2. The epoxy resin according to claim 1, wherein the epoxy resin is at least one selected from the group consisting of an epoxy resin having an alicyclic skeleton, an epoxy resin having a bisphenol skeleton, an epoxy resin having a phenol novolac skeleton, an epoxy resin having a cresol novolac skeleton, an epoxy resin having a norbornene skeleton, an epoxy resin having a terpene skeleton, an epoxy resin having a dicyclopentadiene skeleton, and an epoxy resin having an oxycyclohexane skeleton.

8. The ink jet recording head according to claim 7.

9. 8. The ink jet recording head according to claim 7, wherein the epoxy resin has an epoxy equivalent of 300 g / eq. or less.

10. 8. The ink jet recording head according to claim 7, wherein the epoxy resin comprises an alicyclic epoxy resin.

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