Film-forming agent, film, inkjet head, method for producing film, and siloxane compound

Abstract

Provided are a film-forming agent containing a siloxane compound represented by formula (1), and application thereof. In formula (1), three Xs are each independently an alkoxy group or a halogen atom, L is a divalent linking group, and seven Rs are each independently a monovalent substituent other than halogen atoms.

Description

Film-forming agent, film, inkjet head, film manufacturing method, and siloxane compound

[0001] The present disclosure relates to a film-forming agent, a film, an inkjet head, a method for producing a film, and a siloxane compound.

[0002] Siloxane compounds, which are compounds containing siloxane bonds (Si—O—Si bonds), are used in a variety of fields. For example, Patent Document 1 describes the formation of a water-repellent layer, which is a non-fluorine-based film, using a specific hydrolyzable silicone, which is a siloxane compound.

[0003] Patent Document 1: International Publication No. 2024 / 024461

[0004] For a film formed using a siloxane compound, from the viewpoint of improving the removability of droplets from the film, it may be required to further improve the rolling property of droplets from the film (i.e., to reduce the rolling angle). For example, in an inkjet head having a liquid-repellent layer, the liquid-repellent layer may be formed using a siloxane compound. In this case, from the viewpoint of improving the removability (e.g., washability) of inkjet ink droplets from the liquid-repellent layer, it may be required to further improve the rolling property of droplets from the liquid-repellent layer.

[0005] The present disclosure has been made in view of the above. An object of one embodiment of the present disclosure is to provide a film-forming agent and a method for producing a film capable of forming a film with excellent droplet rolling-off properties, a film with excellent droplet rolling-off properties, an inkjet head provided with a liquid-repellent layer with excellent droplet rolling-off properties, and a siloxane compound having a novel chemical structure.

[0006] The present disclosure includes the following aspects: <1> A film-forming agent containing a siloxane compound represented by the following formula (1):

[0007]

[0008] In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

[0009] <2> Seven R in formula (1) are each independently an alkyl group or —OSiR ２ ３ is a group, ２ ３ Three R in the group ２ are each independently an alkyl group. <3> The film-forming agent according to <1> or <2>, wherein L in formula (1) is a divalent linking group selected from Group A consisting of an alkylene group, an arylene group, an ether group, an ester group, an amide group, a urea group, and a urethane group, or a divalent linking group consisting of a combination of two or more groups selected from Group A. <4> The film-forming agent according to any one of <1> to <3>, wherein, in L in formula (1), the number of atoms present on the path from the silicon atom bonded to one end of L to the silicon atom bonded to the other end of L is 8 or more. <5> The film-forming agent according to any one of <1> to <4>, wherein the siloxane compound represented by formula (1) has 6 or more silicon atoms per molecule. <6> The film-forming agent according to any one of <1> to <5>, which is used for forming a liquid-repellent layer in an inkjet head provided with a liquid-repellent layer. <7> A film containing a siloxane structure represented by the following formula (A):

[0010]

[0011] In formula (A), the three * symbols each represent a bonding position, L represents a divalent linking group, and the seven R symbols each independently represent a monovalent substituent other than a halogen atom.

[0012] <8> An inkjet head having a liquid-repellent layer that is the film according to <7>. <9> A method for producing a film, the method comprising the step of producing a film containing a siloxane structure represented by formula (A) using a siloxane compound represented by formula (1).

[0013]

[0014] In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom. In formula (A), three *s each represent a bonding position, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

[0015] <10> A siloxane compound represented by the following formula (1X):

[0016]

[0017] In formula (1X), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent an alkyl group or -OSiR. ２ ３ is a group, ２ ３ Three R in the group ２ are each independently an alkyl group, and the number of silicon atoms in one molecule of the compound represented by formula (1X) is 6 or more.

[0018] According to one embodiment of the present disclosure, there are provided a film-forming agent and a method for producing a film capable of forming a film with excellent droplet rolling properties, a film with excellent droplet rolling properties, an inkjet head having a liquid-repellent layer with excellent droplet rolling properties, and a siloxane compound having a novel chemical structure.

[0019] Fig. 1 is a schematic cross-sectional view showing one embodiment of an inkjet head according to the present disclosure. Fig. 2 is an enlarged view of the dashed frame A in Fig. 1. Fig. 3 is a diagram showing a modified example of an intermediate layer. Fig. 4 is a schematic cross-sectional view showing a modified example of an inkjet head according to the present disclosure. Fig. 5 is a schematic cross-sectional view showing another embodiment of an inkjet head according to the present disclosure.

[0020] In the present disclosure, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In the present disclosure, when a composition contains multiple substances corresponding to each component, the amount of each component refers to the total amount of the multiple substances present in the composition, unless otherwise specified. In the numerical ranges described in stages in the present disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages, or may be replaced with a value shown in the examples. In the present disclosure, the term "step" includes not only independent steps, but also steps that cannot be clearly distinguished from other steps, as long as the intended purpose of the step is achieved. In the present disclosure, a combination of preferred embodiments is a more preferred embodiment. The elements in the drawings shown in the present disclosure are not necessarily drawn to scale, and emphasis has been placed on clearly illustrating the principles of the present disclosure.

[0021] In the present disclosure, the term "liquid-repellent layer" refers to a layer having a contact angle with water of 60° or more. The contact angle with water is a value measured at 25°C using a contact angle meter, for example, a fully automatic contact angle meter (product name "DM-701", manufactured by Kyowa Interface Science Co., Ltd.). In the present disclosure, the term "ejection surface" refers to the surface of the nozzle substrate on the side from which ink is ejected in an inkjet head. In the present disclosure, the term "inner wall of the ink flow path" refers to the surface on the side of the flow path substrate on which the ink flow path is formed. In addition, the term "inner wall of the nozzle" refers to the surface on the side of the nozzle substrate on which the nozzle is formed.

[0022] [Film-Forming Agent] The film-forming agent of the present disclosure contains a siloxane compound represented by the following formula (1) (hereinafter also referred to as "siloxane compound (1)" or simply "compound (1)").

[0023]

[0024] In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

[0025] The siloxane compound (1) (i.e., the siloxane compound represented by formula (1)) is useful as a component of a film-forming agent. In this case, as shown below, in the siloxane compound (1), "-SiX ３ " is a site (hereinafter referred to as "bonding site") that contributes to bonding between siloxane compounds (1) and / or with other substances. ３ ) ２ The moiety represented by the formula (i.e., the branched siloxane moiety) is the moiety located on the surface side (i.e., the air interface side) of the film to be formed.

[0026]

[0027] By forming a film using a film-forming agent containing siloxane compound (1), a film with excellent droplet rolling properties (i.e., a film with a reduced droplet rolling angle) can be formed. It is believed that the branched siloxane moiety in siloxane compound (1) contributes to the droplet rolling properties. The bonding site in siloxane compound (1) is a site that contributes to bonding between siloxane compounds (1) and / or with other substances. Examples of other substances include compounds other than siloxane compound (1) and the base of the film to be formed (e.g., the surface of a substrate or the surface of a base film).

[0028] A film-forming agent containing the siloxane compound (1) also has the effect of improving the wipe resistance of a film (e.g., a liquid-repellent layer in an inkjet head). The following provides additional information on wipe resistance. Wipe resistance refers to the durability of a film against wiping. For example, components contained in ink may adhere as foreign matter to the ejection surface of an inkjet head (specifically, the ejection surface on which the liquid-repellent layer is provided) when the ink dries after being ejected. If foreign matter adheres to the ejection surface, ejection defects are likely to occur. Therefore, foreign matter can be removed by periodically wiping the ejection surface of the inkjet head. However, wiping may reduce the durability of the ejection surface of the inkjet head. For this reason, durability against wiping (i.e., wipe resistance) may be required.

[0029] Formula (1) and preferred embodiments thereof will be described below.

[0030] In formula (1), three Xs each independently represent an alkoxy group or a halogen atom. The number of carbon atoms in the alkoxy group represented by X is not particularly limited, but is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The halogen atom represented by X is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, more preferably a chlorine atom, a bromine atom, or an iodine atom, even more preferably a chlorine atom or a bromine atom, and even more preferably a chlorine atom.

[0031] In formula (1), L is a divalent linking group.

[0032] L in formula (1) is preferably a divalent linking group consisting of one type selected from Group A consisting of an alkylene group, an arylene group, an ether group, an ester group, an amide group, a urea group, and a urethane group, or a divalent linking group consisting of a combination of two or more types selected from Group A.

[0033] L in formula (1) is more preferably an alkylene group or a divalent linking group formed by a combination of an alkylene group and one selected from Group B consisting of an arylene group, an ether group, an ester group, an amide group, a urea group, and a urethane group.

[0034] There is no particular limitation on the size of L in formula (1) (i.e., the number of constituent atoms). From the viewpoint of further improving the rolling property of droplets in the formed film, in L in formula (1), the number of atoms present on the path from the silicon atom (Si) bonded to one end of this L to the silicon atom (Si) bonded to the other end of this L (hereinafter also referred to as "the number of constituent atoms of the main chain in L") is preferably 2 or more.

[0035] Here, when the number of constituent atoms of the main chain in L (i.e., the number of atoms present on the path from the silicon atom (Si) bonded to one end of L to the silicon atom (Si) bonded to the other end of this L) is defined in multiple ways, it means the minimum value of the multiple defined numbers of atoms.

[0036] The number of atoms constituting the main chain in L is preferably 4 or more, more preferably 6 or more, and even more preferably 8 or more. There is no particular upper limit to the number of atoms constituting the main chain in L, but the upper limit is preferably 20, more preferably 24, and even more preferably 18.

[0037] For example, in specific examples of siloxane compound (1) (compounds A1 to A22 described below), the number of constituent atoms of the main chain in L is as follows: the number of constituent atoms of the main chain in L is 8 in compounds A1 to A4, 9 in compounds A5 to A8, 11 in compound A9, 8 in compounds A13 to A17, 2 in compound A18, and 8 in compounds A19 to A22.

[0038] The total number of constituent atoms of L (i.e., the total number of constituent atoms of the main chain in L and the side chain (substituent) in L) is preferably 6 or more, more preferably 18 or more, and even more preferably 24 or more. There is no particular upper limit to the total number of constituent atoms of L, but the upper limit is preferably 90, more preferably 72, and even more preferably 54.

[0039] In formula (1), seven R's are each independently a monovalent substituent other than a halogen atom. Seven R's are each independently an alkyl group or -OSiR ２ ３ It is preferably a —OSiR group.２ ３ Three R in the group ２ are each independently an alkyl group.

[0040] In formula (1), the alkyl group represented by R preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, even more preferably 1 or 2 carbon atoms, and even more preferably 1 carbon atom.

[0041] -OSiR ２ ３ Motonaka, R. ２ The alkyl group represented by the formula (I) preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, even more preferably 1 or 2 carbon atoms, and even more preferably 1 carbon atom.

[0042] In the siloxane compound represented by formula (1) (i.e., siloxane compound (1)), the number of silicon atoms in one molecule is preferably 6 or more. In this case, the rolling property of droplets in the formed film is further improved. The reason for this is that when the number of silicon atoms in one molecule is 6 or more, the size of the branched siloxane moiety that contributes to the rolling property of droplets increases. Supplementally, the number of silicon atoms in one molecule of siloxane compound (1) is the number of silicon atoms in the branched siloxane moiety plus 1 (i.e., the number of silicon atoms in the bonding moiety). The reason for this is that R does not contain -OSiR ２ ３ Although silicon atoms may be contained in the form of a group, silicon atoms may not be contained in X. Therefore, when the number of silicon atoms in one molecule of the siloxane compound (1) is 6 or more, this means that the number of silicon atoms in the branched siloxane moiety is 5 or more, and at least two of the seven Rs are -OSiR. ２ ３ In this way, when the number of silicon atoms in one molecule of the siloxane compound (1) is 6 or more, the size of the branched siloxane moiety that contributes to the rolling off of droplets increases.

[0043] The number of silicon atoms in one molecule of the siloxane compound (1) is more preferably 7 or more, and even more preferably 8 or more.

[0044] There is no particular upper limit to the number of silicon atoms in one molecule of the siloxane compound (1), but the upper limit is preferably 20, more preferably 16, and even more preferably 12.

[0045] There is no particular upper limit to the molecular weight of the siloxane compound (1), but the upper limit is, for example, 3,000, preferably 1,500, and more preferably 1,200.

[0046] Specific examples of the siloxane compound (1) include compounds A1 to A22 in the examples described below.

[0047] The siloxane compound (1) has a branched siloxane moiety "-SiR(OSiR ３ ) ２ " and a compound for providing a branched siloxane moiety containing a bonding moiety "-SiX ３ " and a compound for providing a binding site containing ", and then reacting them (see each example described later).

[0048] Preferably, the branched siloxane moiety supplying compound and the bonding site supplying compound each independently have a reactive site. The branched siloxane moiety supplying compound may be a compound in which the bonding site and L in formula (1) are replaced with hydrogen atoms. In this case, the Si—H bond serves as the reactive site in the branched siloxane moiety supplying compound. In this case, the bonding site supplying compound preferably contains a vinyl group as the reactive site (see, for example, Examples 1 to 4 described below).

[0049] The compound for providing branched siloxane moieties may be a compound containing an amino group as a reactive site, and in this case, the compound for providing bonding sites preferably contains an isocyanate group as a reactive site (see, for example, Examples 5 to 8 below).

[0050] The amino group-containing compound for supplying a branched siloxane moiety may be synthesized by synthesizing a compound in which the bonding site and L in formula (1) are replaced with hydrogen atoms, and a compound containing a vinyl group and a phthalimide group, and then converting the phthalimide group in the resulting compound to an amino group (see, for example, Example 9 described below).

[0051] In addition to the above-mentioned examples, other combinations of reactive moieties in the branched siloxane moiety-supplying compound and the bonding moiety-supplying compound include a combination of a hydroxy group with a hydroxy group, a combination of a hydroxy group with a carboxy group, and a combination of an amino group with an amino group.

[0052] The film-forming agent of the present disclosure is preferably used as a film to form a liquid-repellent layer in an inkjet head, in which case a liquid-repellent layer with excellent ink droplet rolling-off properties can be formed.

[0053] [Film] The film of the present disclosure contains a siloxane structure represented by the following formula (A) (hereinafter also referred to as siloxane structure (A)).

[0054]

[0055] In formula (A), the three * symbols each represent a bonding position, L represents a divalent linking group, and the seven R symbols each independently represent a monovalent substituent other than a halogen atom.

[0056] In formula (A), L and seven R have the same meanings as L and seven R in formula (1), respectively, and preferred embodiments are also the same.

[0057] The siloxane structure (A) is a residue obtained by removing three Xs from the siloxane compound (1). Like the siloxane compound (1), the siloxane structure (A) also has the structure "-SiR(OSiR ３ ) ２ Therefore, the film of the present disclosure containing the siloxane structure (A) exhibits the same effects as the siloxane compound of the present disclosure described above (particularly, the effect of being able to form a film with excellent droplet rolling properties).

[0058] The film of the present disclosure is preferably produced using a siloxane compound (1). In this case, at least one of the three Xs at the bonding site in the siloxane compound (1) bonds with another siloxane compound (1) and / or other substance. In this case, at least one of the three Xs may remain as X.

[0059] Preferred aspects of the film of the present disclosure (such as film thickness) are the same as the preferred aspects of the liquid-repellent layer described below.

[0060] The film of the present disclosure may contain the following siloxane structure (B) in addition to the above-described siloxane structure (A), which further improves the droplet rolling properties and the wipe resistance of the film.

[0061] Examples of the siloxane structure (B) include a structure represented by the following formula (B1), a silanol group (Si—OH group), and a group represented by A in the following formula (B1).

[0062]

[0063] In formula (B1), A is a hydrophilic group, L is a divalent linking group, and the three *'s each represent a bonding position.

[0064] Each of the three *'s in formula (B1) is bonded to, for example, an alkoxy group, a halogen atom, or another substance. Examples of the other substance referred to here include the adjacent siloxane structure (B), the siloxane structure (A), and the underlayer of the film to be formed (for example, the surface of the substrate or the surface of the underlayer film (for example, the surface of the intermediate layer described below)). The number of carbon atoms in the alkoxy group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The halogen atom is preferably a fluorine atom, chlorine atom, bromine atom, or iodine atom, more preferably a chlorine atom, bromine atom, or iodine atom, even more preferably a chlorine atom or bromine atom, and even more preferably a chlorine atom.

[0065] A in formula (B1) is a hydrophilic group. A in formula (B1) is preferably a monovalent group containing at least one selected from the group consisting of an amide group, a urea group, a urethane group, a hydroxyl group, a carboxy group, and an amino group, and more preferably a monovalent group containing at least one selected from the group consisting of an amide group, a urea group, and a urethane group.

[0066] Examples of the hydrophilic group represented by A include an aminocarbonylamino group, an alkylcarbonylamino group (preferably an alkylcarbonylamino group containing an alkyl group having 1 to 6 carbon atoms), a carboxyalkyleneamino group (preferably a carboxyalkyleneamino group containing an alkylene group having 1 to 6 carbon atoms), an arylaminocarbonylamino group (preferably an arylaminocarbonylamino group containing an aryl group having 6 to 12 carbon atoms), an alkylaminocarbonylamino group (preferably an arylaminocarbonylamino group containing an alkyl group having 1 to 6 carbon atoms), an imidazolidinon-2-ylalkyleneaminocarbonylamino group (preferably an imidazolidinon-2-ylalkyleneaminocarbonylamino group containing an alkylene group having 1 to 6 carbon atoms), an amino group, a carboxy group, a hydroxyl group, a dicarboxylic acid residue (more specifically, a residue in which one hydrogen atom has been removed from the hydrocarbon chain of a dicarboxylic acid), an alkyloxycarbonylamino group (preferably an alkyloxycarbonylamino group containing an alkyl group having 1 to 6 carbon atoms), etc.

[0067] L in formula (B1) is a divalent linking group, and is preferably a divalent linking group consisting of one type selected from Group X consisting of an alkylene group, an arylene group, an ether group, and an ester group, or a divalent linking group consisting of two or more types selected from Group X.

[0068] There is no particular limitation on the size (i.e., the number of constituent atoms) of L in formula (B1). From the viewpoint of further improving the rolling-off properties of droplets on the liquid-repellent layer to be formed, the number of constituent atoms of the main chain in L in formula (B1) is preferably 2 or more.

[0069] Here, the number of constituent atoms of the main chain in L in formula (B1) means the number of atoms present on the path from A (hydrophilic group) bonded to one end of L to the silicon atom (Si) bonded to the other end of L in formula (B1). For example, when L is a linear alkylene group, the number of constituent atoms of the main chain in L corresponds to the number of carbon atoms in the linear alkylene group. Note that, when the number of constituent atoms of the main chain in L is defined in multiple ways, it means the smallest value among the multiple defined numbers of atoms.

[0070] There is no particular upper limit to the number of atoms constituting the main chain in L, but the upper limit is preferably 20, more preferably 16, even more preferably 12, even more preferably 10, and even more preferably 8.

[0071] The structure represented by formula (B1) can be formed using a compound represented by formula (B1X): The formation of the structure represented by formula (B1) using the compound represented by formula (B1X) is preferably carried out by a gas phase process (e.g., vapor deposition).

[0072]

[0073] In formula (B1X), A represents a hydrophilic group, L represents a divalent linking group, and each of the three Xs independently represents an alkoxy group or a halogen atom.

[0074] In formula (B1X), three Xs each independently represent an alkoxy group or a halogen atom. The number of carbon atoms in the alkoxy group represented by X is not particularly limited, but is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The halogen atom represented by X is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, more preferably a chlorine atom, a bromine atom, or an iodine atom, even more preferably a chlorine atom or a bromine atom, and even more preferably a chlorine atom.

[0075] A and L in formula (B1X) have the same meanings as A and L in formula (B1), respectively, and preferred embodiments are also the same.

[0076] Specific examples of the compound represented by formula (B1X) include the following compounds (B1X-1) to (B1X-9).

[0077]

[0078] The structure represented by formula (B1) can be formed, for example, by depositing a compound represented by formula (B1X) before depositing the siloxane compound (1) (i.e., forming the siloxane structure (A)).

[0079] [Method for Producing Film] The method for producing a film according to the present disclosure includes a step of producing a film containing a siloxane structure represented by formula (A) using a siloxane compound represented by formula (1).

[0080]

[0081] In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom. In formula (A), three *s each represent a bonding position, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

[0082] The siloxane compound represented by formula (1) and the siloxane structure represented by formula (A) are as described above.

[0083] According to the method for producing a film of the present disclosure, a film having excellent rolling properties can be formed. The formed film also has excellent wipe resistance.

[0084] A preferred embodiment of the step of producing a film containing a siloxane structure represented by formula (A) using a siloxane compound represented by formula (1) is the same as the method of forming a liquid-repellent layer described below.

[0085] [Inkjet head] The inkjet head of the present disclosure includes a liquid-repellent layer that is the film of the present disclosure, and therefore has the same effects as the film of the present disclosure (particularly, the effect of excellent droplet rolling off).

[0086] An example of an inkjet head according to the present disclosure includes a nozzle substrate having nozzles formed thereon for ejecting inkjet ink (hereinafter also simply referred to as ink), and a liquid-repellent layer, which is a film according to the present disclosure, provided on the ejection surface of the nozzle substrate. In this case, the liquid-repellent layer is preferably located on the outermost surface of the nozzle substrate. When multiple layers are provided on the nozzle substrate, the liquid-repellent layer is preferably the outermost layer of the multiple layers.

[0087] The liquid-repellent layer (for example, the liquid-repellent layer 52 described below) is preferably a layer having a contact angle with water of 60° or more. The contact angle with water of the liquid-repellent layer is more preferably 70° or more, and even more preferably 80° or more. Since the liquid-repellent layer is provided on the outermost surface of the nozzle substrate 10, the ejection surface has excellent wipe resistance.

[0088] The thickness of the liquid-repellent layer is preferably 0.5 nm to 10 nm, and more preferably 1 nm to 3 nm. When the thickness of the liquid-repellent layer is 0.5 nm or more, the wipe resistance is improved.

[0089] Hereinafter, an embodiment of an inkjet head according to the present disclosure will be described with reference to the drawings.

[0090] FIG. 1 is a cross-sectional view showing an embodiment of an inkjet head according to the present disclosure.

[0091] 1, an inkjet head 100, which is one embodiment of the inkjet head of the present disclosure, includes an inkjet head having a nozzle substrate 10 in which nozzles 30 for ejecting ink are formed, and a flow path substrate 20 in which ink flow paths 40 communicating with the nozzles 30 are formed. The nozzle substrate 10 and the flow path substrate 20 are preferably joined by adhesion or the like.

[0092] <Ink> There are no particular limitations on the type of ink supplied to the inkjet head 100. The inkjet head 100 can eject fine droplets (i.e., ink droplets) from the nozzles 30 by incorporating it into an ink ejection device described below.

[0093] The ink is, for example, an ink containing a coloring material and a liquid component. Examples of the ink include: a water-based ink containing a coloring material and water; a UV ink (i.e., ultraviolet-curable ink) containing a coloring material and a polymerizable compound; and the like.

[0094] The surface tension of the ink is preferably 20 mN / m to 40 mN / m.

[0095] In the present disclosure, the surface tension of the ink refers to a value measured at 25° C. The surface tension of the ink is measured using a surface tensiometer (for example, product name "DY-700" manufactured by Kyowa Interface Science Co., Ltd.).

[0096] Generally, the lower the surface tension of ink, the more easily it spreads on the ejection surface, and therefore tends to have poorer rolling properties (i.e., a higher rolling angle) on the ejection surface. However, the liquid-repellent layer of the present disclosure can achieve excellent rolling properties (low rolling angle) even for inks with low surface tensions (e.g., inks with a surface tension of 20 mN / m to 30 mN / m). For this reason, the film-forming agent and film of the present disclosure are particularly effective for inks with low surface tensions (e.g., inks with a surface tension of 20 mN / m to 30 mN / m).

[0097] Furthermore, the ink supplied to the inkjet head 100 may be either an acidic ink or an alkaline ink. The inkjet head 100 is suitable for alkaline inks because the ejection surface and the inside of the flow path have excellent alkali resistance. In particular, the inkjet head 100 is suitable for inks with a pH of 8 to 11. The pH is a value measured at 25°C using a pH meter, for example, a value measured using a product named "Handy pH Meter" manufactured by Sato Keiryoki Seisakusho.

[0098] <Preferred embodiment of ink> The ink preferably contains a polymerizable compound. Such a preferred embodiment of the ink is suitable as the aforementioned UV ink.

[0099] The polymerizable compound is preferably at least one selected from the group consisting of (meth)acrylate compounds and N-vinyl compounds.

[0100] In a preferred embodiment, the ink more preferably contains at least one compound selected from the group consisting of (meth)acrylate compounds and N-vinyl compounds, a photopolymerization initiator, and an organic solvent, and even more preferably contains at least one compound selected from the group consisting of (meth)acrylate compounds and N-vinyl compounds, a photopolymerization initiator, an organic solvent, and a colorant.

[0101] ((Meth)acrylate Compound) In the present disclosure, a (meth)acrylate compound refers to an acrylate compound or a methacrylate compound, and a (meth)acryloyloxy group refers to an acryloyloxy group or a methacryloyloxy group. In the (meth)acrylate compound, the number of (meth)acryloyloxy groups is not particularly limited and is, for example, 1 to 6, and from the viewpoint of providing an image layer with better flexibility and alcohol resistance, 2 to 6 is preferred, 2 to 4 is more preferred, and 2 to 3 is even more preferred. The (meth)acrylate compound may be any of a monomer, an oligomer, or a mixture thereof.

[0102] Examples of the monofunctional (meth)acrylate compound (a compound selected from the group consisting of a monofunctional acrylate compound and a monofunctional methacrylate compound) include phenoxyethyl acrylate (PEA), 2-propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester (VEEA), cyclic TMP formal acrylate (CTFA), isobornyl acrylate (IBOA), tetrahydrofurfuryl acrylate (THFA), 2-(2-ethoxyethoxy)ethyl acrylate, octadecyl acrylate (ODA), tridecyl acrylate (TDA), isodecyl acrylate (IDA), and lauryl acrylate, and among these, 2-propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester (VEEA) is preferred.

[0103] Examples of polyfunctional (meth)acrylate compounds (compounds selected from the group consisting of polyfunctional acrylate compounds and polyfunctional methacrylate compounds) include hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, polyethylene glycol diacrylate (e.g., tetraethylene glycol diacrylate), dipropylene glycol diacrylate, tri(propylene glycol) triacrylate, neopentyl glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, bis(pentaerythritol)hexaacrylate, and acrylate esters of ethoxylated or propoxylated glycols and polyols (e.g., propoxylated neopentyl glycol diacrylate, ethoxylated trimethylolpropane triacrylate, and mixtures thereof). Specific examples of polyfunctional (meth)acrylate compounds include hexanediol dimethacrylate, trimethylolpropane trimethacrylate, triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, and 1,4-butanediol dimethacrylate, among which 3-methyl-1,5-pentanediol diacrylate and dipropylene glycol diacrylate are preferred.

[0104] As the N-vinyl compound, N-vinylpyrrolidone (NVP) or N-vinylcaprolactam (NVC) is preferred, and N-vinylcaprolactam (NVC) is particularly preferred.

[0105] The total content of the (meth)acrylate compound and the N-vinyl compound in the ink is preferably 80% by mass to 100% by mass, more preferably 90% by mass to 100% by mass or more, and even more preferably 95% by mass to 100% by mass or more, based on the total mass of the polymerizable compounds in the ink.

[0106] The content of the polymerizable compound in the ink is preferably 50% by mass to 95% by mass, more preferably 50% by mass to 90% by mass, and even more preferably 60% by mass to 90% by mass, based on the total solid content of the ink.

[0107] (Photopolymerization Initiator) The ink preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include radical photopolymerization initiators. Examples of radical photopolymerization initiators include benzophenone, 1-hydroxycyclohexyl phenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-benzyl-2-dimethylamino-(4-morpholinophenyl)butan-1-one, isopropyl thioxanthone, benzyl dimethyl ketal, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and bis(2,6-dimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide. Commercially available radical photopolymerization initiators include IRGACURE (registered trademark), Darocur (registered trademark), and LUCIRIN (registered trademark) (all manufactured by BASF). The content of the photopolymerization initiator in the ink is preferably 1% by mass to 20% by mass, and more preferably 1% by mass to 15% by mass, based on the total solid content of the ink.

[0108] A pretreatment liquid may be ejected onto the substrate before the ink is ejected onto the substrate, or a posttreatment liquid may be ejected after the ink is ejected. Therefore, the ink supplied to the inkjet head 100 includes not only the ink but also a pretreatment liquid and a posttreatment liquid. The pretreatment liquid and the posttreatment liquid are usually colorless inks that do not contain coloring materials.

[0109] <Nozzle Substrate> The nozzle substrate 10 is, for example, a substrate made of silicon, and may be a single crystal silicon substrate or a polycrystalline silicon substrate. The nozzle substrate 10 has nozzles 30 formed thereon that eject ink.

[0110] The nozzles 30 are holes that penetrate the nozzle substrate 10 and are formed by, for example, dry etching. It is preferable that a plurality of nozzles 30 are formed on the nozzle substrate 10. There are no particular limitations on the shape of the nozzles 30, but from the perspective of controlling the ink ejection direction, it is preferable that the nozzles 30 have a tapered shape in which the diameter decreases in the ink ejection direction. The hole diameter of the nozzle 30 on the ink ejection side, i.e., the hole diameter of the nozzle opening 31, can be adjusted as appropriate. When the inkjet head 100 is used as an inkjet head, the hole diameter of the nozzle opening 31 is, for example, 10 μm to 30 μm.

[0111] The thickness of the nozzle substrate 10 corresponds to the length of the nozzle 30 and is preferably 10 μm to 100 μm, and more preferably 20 μm to 60 μm.

[0112] FIG. 2 is an enlarged view of the dashed frame A in FIG.

[0113] 2, an intermediate layer 51 and a liquid-repellent layer 52 are provided in this order on the ejection surface 101 of the nozzle substrate 10. If the intermediate layer 51 is included between the nozzle substrate and the liquid-repellent layer, corrosion of the nozzle substrate 10 due to deterioration of the liquid-repellent layer 52 can be suppressed.

[0114] The intermediate layer 51 is made of tantalum oxide, zirconium oxide, titanium oxide, hafnium oxide, SiO ２ It is preferable that the layer contains at least one material selected from the group consisting of SiC, SiN, SiCN, and SiON.

[0115] At least one selected from the group consisting of tantalum oxide, zirconium oxide, titanium oxide, and hafnium oxide (preferably tantalum oxide, zirconium oxide, or hafnium oxide) has excellent alkali resistance. Therefore, when alkaline ink penetrates into the liquid-repellent layer 52 provided on the ejection surface of the nozzle substrate after long-term use, the presence of the intermediate layer 51 makes it possible to maintain the alkali resistance of the ejection surface. ２ , a layer containing at least one selected from the group consisting of SiC, SiN, SiCN and SiON (preferably, SiO ２The ink layer 52 has high adhesion to the liquid-repellent layer 52. Therefore, alkaline ink is less likely to penetrate into the liquid-repellent layer 52, and the ink ejection surface has excellent alkali resistance.

[0116] The thickness of the intermediate layer 51 is preferably 0.3 nm to 100 nm, and more preferably 0.5 nm to 50 nm. If the thickness of the intermediate layer 51 is 100 nm or less, the stress in the film does not become too large, and cracks are less likely to occur. If the thickness of the intermediate layer 51 is 0.3 nm or more, the film tends to be uniform, and adhesion to the liquid-repellent layer is improved.

[0117] From the viewpoint of further enhancing the wipe resistance and alkali resistance of the ejection surface, it is preferable that the intermediate layer 51 is made up of two layers, and that a first intermediate layer 51A, a second intermediate layer 51B, and a liquid-repellent layer 52 are provided in this order on the ejection surface 101 of the nozzle substrate 10, as shown in FIG.

[0118] The first intermediate layer 51A is preferably a layer containing at least one selected from the group consisting of tantalum oxide, zirconium oxide, titanium oxide, and hafnium oxide, and more preferably a layer of tantalum oxide, zirconium oxide, or hafnium oxide.

[0119] At least one selected from the group consisting of tantalum oxide, zirconium oxide, titanium oxide, and hafnium oxide (preferably tantalum oxide, zirconium oxide, or hafnium oxide) has excellent alkali resistance. Therefore, even if alkaline ink penetrates into the liquid-repellent layer 52 and second intermediate layer 51B provided on the ejection surface of the nozzle substrate after long-term use, the presence of the first intermediate layer 51A makes it possible to maintain the alkali resistance of the ejection surface.

[0120] The thickness of the first intermediate layer 51A is preferably 3 nm to 70 nm, more preferably 10 nm to 50 nm, and even more preferably 20 nm to 50 nm. When the thickness of the first intermediate layer 51A is 3 nm or more, alkaline ink is less likely to penetrate, and the ejection surface has better wiping resistance and alkali resistance. On the other hand, when the thickness of the first intermediate layer 51A is 70 nm or less, defects are less likely to occur within the layer, and the ejection surface has better wiping resistance and alkali resistance. From the viewpoint of productivity, the thickness of the first intermediate layer 51A is preferably 50 nm or less.

[0121] The second intermediate layer 51B is made of SiO ２ , SiC, SiN, SiCN, and SiON, and ２ More preferably, it is a layer.

[0122] SiO ２ , a layer containing at least one selected from the group consisting of SiC, SiN, SiCN and SiON (preferably, SiO ２ The second intermediate layer 51B has high adhesion to the liquid-repellent layer 52. Therefore, alkaline ink is less likely to penetrate into the liquid-repellent layer 52 and the second intermediate layer 51B, and the ejection surface has excellent wipe resistance and alkali resistance.

[0123] The thickness of the second intermediate layer 51B is preferably 0.3 nm to 120 nm, more preferably 0.3 nm to 3 nm or 10 nm to 100 nm, even more preferably 0.3 nm to 3 nm, and particularly preferably 0.5 nm to 2 nm. In particular, when the thickness of the second intermediate layer 51B is 0.3 nm to 3 nm or 10 nm to 100 nm, the adhesion between the second intermediate layer 51B and the liquid-repellent layer 52 is enhanced, and the wipe resistance and alkali resistance of the ejection surface are superior.

[0124] The liquid-repellent layer 52 includes the siloxane structure represented by formula (A) described above. The liquid-repellent layer 52 is formed using the film-forming agent of the present disclosure described above. Preferred aspects of the liquid-repellent layer are as described above. For example, before the formation of the siloxane structure represented by formula (A), a compound represented by formula (B1X) described above may be vapor-deposited to form the structure represented by formula (B1).

[0125] 1 and 2, the inkjet head 100 has an intermediate layer 51 on the inner wall 102 of the nozzle 30. The intermediate layer 51 provided on the inner wall 102 of the nozzle 30 is the same as the intermediate layer 51 provided on the ejection surface 101 of the nozzle substrate 10. On the inner wall 102 of the nozzle 30, the intermediate layer 51 is the outermost layer. It is preferable that the layer formed on the inner wall 102 of the nozzle 30 does not contain a fluorine compound.

[0126] <Flow Channel Substrate> The flow channel substrate 20 is, for example, a substrate made of silicon, and may be a single crystal silicon substrate or a polycrystalline silicon substrate. As shown in Fig. 1, the flow channel substrate 20 is made of a wall member 21 and a lid member 22, and it is preferable that the wall member 21 and the lid member 22 are joined by adhesive or the like. An ink flow channel 40 that communicates with the nozzle 30 is formed in the flow channel substrate 20. The ink flow channel 40 includes a nozzle communication channel 41, a pressure chamber 42, and an ink supply channel 43.

[0127] The nozzle communication passage 41 is a flow path that connects the pressure chamber 42 and the nozzle 30. The nozzle communication passage 41 is preferably linear in cross section.

[0128] The pressure chamber 42 is a flow path whose volume changes when a drive voltage is applied. For example, the pressure chamber 42 has a substantially square planar shape when the inkjet head 100 is viewed from above, with an ink outlet to the nozzle communication path 41 provided at one of the diagonal corners and an ink supply path 43 which is an ink inlet provided at the other. The planar shape of the pressure chamber 42 is not limited to a substantially square, and may be rectangular, trapezoidal, etc.

[0129] The ink supply path 43 is a flow path that is connected to a liquid tank (not shown) when the inkjet head 100 is incorporated into an ink ejection device (described later). Ink is supplied from the liquid tank to the pressure chamber 42 via the ink supply path 43. The arrows in the figure indicate the direction of ink flow. The liquid tank (not shown) and the inkjet head 100 are connected by, for example, a tube. It is preferable that the tube does not contain a fluorine compound.

[0130] The inkjet head 100 has an intermediate layer 51 on the inner wall 201 of the ink flow path 40, similar to the intermediate layer 51 on the inner wall 102 of the nozzle 30 shown in Fig. 1. The intermediate layer 51 provided on the inner wall 201 of the ink flow path 40 is the same as the intermediate layer 51 provided on the ejection surface 101 of the nozzle substrate 10. The inner wall 201 of the ink flow path 40 specifically includes the surface of the wall member 21 on which the ink flow path 40 is formed, the surface of the cover member 22 on which the ink flow path 40 is formed, and the surface of the nozzle substrate 10 on which the ink flow path 40 is formed. On the inner wall 201 of the ink flow path 40, the intermediate layer 51 is the outermost layer. It is preferable that the layer formed on the inner wall 201 of the ink flow path 40 does not contain a fluorine compound.

[0131] The structure of the flow path substrate 20 may be, for example, the structure shown in Fig. 4 other than the structure shown in Fig. 1. Fig. 4 shows an example in which the intermediate layer 51 is made up of two layers, a first intermediate layer 51A and a second intermediate layer 51B.

[0132] FIG. 4 is a schematic cross-sectional view showing a modified example of the inkjet head of the present disclosure.

[0133] 4, the inkjet head 100A includes a nozzle substrate 10 and a flow path substrate 20A in which ink flow paths 60 communicating with the nozzles 30 are formed. The configuration of the nozzle substrate 10 is as described above. The ink flow paths 60 include nozzle communication paths 61, pressure chambers 62, ink supply paths 63, and circulation paths 64.

[0134] The nozzle communication passage 61 is similar to the nozzle communication passage 41 described above, and is a flow path that connects the pressure chamber 62 and the nozzle 30 .

[0135] The pressure chamber 62 is similar to the pressure chamber 42 described above, and is a flow path whose volume changes when a drive voltage is applied.

[0136] The ink supply path 63 is similar to the ink supply path 43 described above, and is a flow path that is connected to a liquid tank (not shown) when the inkjet head 100A is incorporated into an ink ejection device described below. Ink is supplied from the liquid tank to the pressure chamber 62 via the ink supply path 63.

[0137] The circulation flow path 64 is a flow path that is connected to a liquid tank (not shown) when the inkjet head 100A is incorporated into an ink ejection device described below. Ink is sent to the nozzles 30 through the ink supply paths 63, the pressure chambers 62, and the nozzle communication paths 61, but ink that is not ejected from the nozzle openings 31 of the nozzles 30 passes through the circulation flow path 64 and is collected in the liquid tank.

[0138] The inkjet head 100A has an intermediate layer 51 on the inner wall 201A of the ink flow path 60, similar to the intermediate layer 51 on the inner wall 201 of the ink flow path 40. The intermediate layer 51 on the inner wall 201A of the ink flow path 60 is the same as the intermediate layer 51 on the inner wall 201 of the ink flow path 40.

[0139] <Layer Formation Method> Next, a method for forming the first intermediate layer 51A, the second intermediate layer 51B, and the liquid-repellent layer 52 on the nozzle substrate 10, the nozzle 30, and the flow path substrate 20 will be described. The first intermediate layer 51A, the second intermediate layer 51B, and the liquid-repellent layer 52 are preferably formed after bonding the nozzle substrate 10 and the flow path substrate 20 to obtain a bonded body. When the intermediate layer is a single layer, it can be formed by the same method as when it is a two-layer layer. The method for forming the intermediate layer is not particularly limited, and may be atomic layer deposition (ALD) or chemical vapor deposition (CVD). The intermediate layer may also be formed by film formation by sputtering. When film formation by sputtering is used, it is preferable to form the intermediate layer separately on the nozzle substrate 10 and the flow path substrate 20, and then bond the nozzle substrate 10 and the flow path substrate 20.

[0140] First, before forming the first intermediate layer 51A on the surface of the bonded assembly of the nozzle substrate 10 and the flow path substrate 20, it is preferable to perform a surface treatment on the surface of the bonded assembly in advance. Examples of surface treatments include UV ozone treatment and oxygen plasma treatment. Of these, oxygen plasma treatment is preferable from the viewpoint of improving the adhesion between the bonded assembly and the first layer. The oxygen plasma irradiation conditions can be adjusted as appropriate, and are performed under conditions of, for example, an output of 100 W to 200 W, a flow rate of 50 mL / min to 200 mL / min, and an irradiation time of 1 minute to 10 minutes.

[0141] Next, a first intermediate layer 51A is formed on the surface of the surface-treated bonded body. Specifically, the first intermediate layer 51A is formed on the ejection surface 101 of the nozzle substrate 10, the inner wall 102 of the nozzle 30, and the inner wall 201 of the ink flow path 40.

[0142] The first intermediate layer 51A is preferably formed by atomic layer deposition (ALD). A commonly known method can be used as the ALD method. The ALD method forms a dense layer, which is highly effective in suppressing the penetration of alkaline ink.

[0143] The first intermediate layer 51A is formed by, for example, placing the surface-treated bonded body in an ALD chamber and ２ After introducing O gas, a precursor gas is introduced, an excess gas is exhausted, and H ２ The formation can be achieved by repeatedly performing four steps: a step of introducing O gas and a step of exhausting excess gas.

[0144] First, H ２ By introducing O gas, hydroxyl groups are formed on the surface of the bonded body. Next, by introducing a precursor gas, the hydroxyl groups formed on the surface of the bonded body react with the precursor. ２ By introducing O gas, the precursor reacted with the hydroxyl group and H ２ It reacts with O.

[0145] Examples of precursors used when forming a tantalum oxide layer as the first intermediate layer 51A include tert-butyliminotri(diethylamino)tantalum (TBTDET), tert-butyliminotri(dimethylamino)tantalum (TBTDMT), tert-butyliminotri(ethylmethylamino)tantalum (TBTEMT), ethyliminotri(diethylamino)tantalum (EITDET), ethyliminotri(dimethylamino)tantalum (EITDMT), ethyliminotri(ethylmethylamino)tantalum (EITEMT), tert-amyliminotri(dimethylamino)tantalum (TAIMAT), tert-amyliminotri(diethylamino)tantalum, pentakis(dimethylamino)tantalum, and tert-amyliminotri(ethylmethylamino)tantalum.

[0146] Precursors used when forming a zirconium oxide layer as the first intermediate layer 51A include, for example, tetrakis(N-ethylmethylamino)zirconium (TEMAZ) and tris(dimethylamino)cyclopentadienylzirconium (ZAC).

[0147] Precursors used when forming a titanium oxide layer as the first intermediate layer 51A include, for example, tetrakis(dimethylamino)titanium (TDMAT), tetrakis(diethylamino)titanium (TDEAT), and tetrakis(ethylmethylamino)titanium (TEMAT).

[0148] Precursors used when forming a hafnium oxide layer as the first intermediate layer 51A include, for example, tetrakis(dimethylamino)hafnium (TDMAHf), tetrakis(diethylamino)hafnium (TDEAHf), and tetrakis(ethylmethylamino)hafnium (TEMAHf).

[0149] In addition, when forming the first intermediate layer 51A, H ２ Ozone gas may be used instead of O gas.

[0150] Next, the second intermediate layer 51B is formed on the first intermediate layer 51A.

[0151] The method for forming the second intermediate layer 51B is not particularly limited, and examples thereof include chemical vapor deposition (CVD). A commonly known method can be used as the CVD method. It is more preferable that the second intermediate layer 51B be formed by atomic layer deposition (ALD). A commonly known method can be used as the ALD method. The ALD method forms a dense layer, which is highly effective in suppressing the penetration of alkaline ink.

[0152] Next, the liquid-repellent layer 52 is formed on the second intermediate layer 51B.

[0153] Although the method for forming the liquid-repellent layer 52 is not particularly limited, it is preferable to perform a hydrophilization treatment on the surface of the second intermediate layer 51B and then use the film-forming agent of the present disclosure to form the liquid-repellent layer 52. In this case, the film-forming agent of the present disclosure is hydrolyzed and then bonds with the hydrophilic groups formed on the surface of the second intermediate layer 51B, thereby improving adhesion between the liquid-repellent layer 52 and the second intermediate layer 51B and suppressing penetration of alkaline ink.

[0154] Examples of hydrophilization treatments include UV ozone treatment and oxygen plasma treatment. Of these, oxygen plasma treatment is preferred. The irradiation conditions can be adjusted as appropriate, and are, for example, performed under conditions of an output of 100 W to 200 W, a flow rate of 50 mL / min to 200 mL / min, and an irradiation time of 1 minute to 10 minutes.

[0155] There are no particular limitations on the method for forming a liquid-repellent layer using the film-forming agent of the present disclosure. Formation of a liquid-repellent layer using the film-forming agent of the present disclosure can be carried out, for example, by a vapor deposition method. Formation of a liquid-repellent layer by a vapor deposition method can be carried out, for example, by placing an assembly in which the first intermediate layer 51A and the second intermediate layer 51B are stacked in a vacuum chamber and placing the film-forming agent of the present disclosure in a vapor deposition boat. The vapor deposition temperature is preferably 100°C to 300°C.

[0156] The liquid-repellent layer can also be formed using the film-forming agent of the present disclosure by the molecular vapor deposition (MVD) method.

[0157] The liquid-repellent layer may be formed using the film-forming agent of the present disclosure by a method other than the vapor deposition method and the MVD method.

[0158] In order to further improve the adhesion between the second intermediate layer 51B and the liquid-repellent layer 52, the bonded body formed by stacking the first intermediate layer 51A, the second intermediate layer 51B, and the liquid-repellent layer 52 is preferably kept in a high-temperature, high-humidity environment after film formation. For example, the bonded body formed by stacking the first intermediate layer 51A, the second intermediate layer 51B, and the liquid-repellent layer 52 is kept at a temperature of 50° C. to 90° C. and a relative humidity of 50% to 90% for 6 hours to 24 hours.

[0159] Next, the liquid-repellent layer 52 provided on the inner wall 102 of the nozzle 30 and the inner wall 201 of the ink flow path 40 is removed.

[0160] For example, by applying tape to the surface of the liquid-repellent layer 52 provided on the ejection surface of the nozzle substrate 10 and performing oxygen plasma treatment on the nozzle 30 and the ink flow path 40, the liquid-repellent layer 52 provided on the inner wall 102 of the nozzle 30 and the inner wall 201 of the ink flow path 40 can be removed.

[0161] FIG. 5 is a cross-sectional view showing another embodiment of the inkjet head of the present disclosure.

[0162] As shown in FIG. 5, the inkjet head 500 further includes a piezoelectric element 70 in addition to the components of the inkjet head 100A.

[0163] The inkjet head 100A has the above-described structure. The cover member 22 of the inkjet head 100A functions as a vibration plate in the inkjet head 500.

[0164] A piezoelectric element 70 having a laminated structure of a lower electrode 71, a piezoelectric layer 72, and an upper electrode 73 is disposed on the cover member (vibration plate) 22. The piezoelectric element 70 is provided above the pressure chamber 62.

[0165] The upper electrode 73 is an individual electrode patterned to correspond to the shape of the pressure chamber 62. When a drive voltage is applied to the upper electrode 73 of the piezoelectric element 70 provided above the pressure chamber 62 in accordance with input data, the piezoelectric element 70 and the lid member (vibration plate) 22 deform, changing the volume of the pressure chamber 62. The change in pressure within the pressure chamber 62 causes ink to be ejected from the nozzle opening 31 of the nozzle 30 via the nozzle communication passage 61.

[0166] Instead of the piezoelectric element, a heater may be provided inside the pressure chamber 62 as a pressure generating element, and a driving voltage may be supplied to the heater to generate heat, thereby ejecting ink from the pressure chamber 62 from the nozzle opening 31 using the film boiling phenomenon.

[0167] [Ink Discharge Apparatus] The ink discharge apparatus of the present disclosure includes an inkjet head, a conveying unit that conveys a substrate, and a drying unit that dries the ink discharged onto the substrate. An inkjet recording apparatus, which is an example of an ink discharge apparatus, will be described below.

[0168] An inkjet recording device includes, for example, a plurality of inkjet heads (an example of an inkjet head) provided for each ink color, an ink storage section for storing the ink to be supplied to each inkjet head, a paper feed section for supplying the substrate (recording paper), a decurling processing section for removing curls from the recording paper, a transport section arranged opposite the ejection surface of each inkjet head for transporting the recording paper, a drying section for drying the ink (specifically, the ink) ejected onto the recording paper, an image detection section for reading the image recording results, and a paper ejection section for ejecting the recorded image to the outside.

[0169] The configurations of the inkjet recording apparatus other than the inkjet head are the same as conventionally known configurations, and reference can be made to, for example, International Publication No. 2017 / 073526 and Japanese Patent Application Laid-Open No. 2022-049414.

[0170] The ink ejection device of the present disclosure preferably has a liquid circulation mechanism for circulating ink between the inkjet head and the liquid tank. For example, by using an inkjet head including the inkjet head 100A shown in FIG. 4, ink can be circulated between the inkjet head and the liquid tank.

[0171] [Method for manufacturing an inkjet head] The method for manufacturing an inkjet head according to the present disclosure includes forming a liquid-repellent layer on an ejection surface of a nozzle substrate on which nozzles for ejecting ink are formed, using the film-forming agent according to the present disclosure. The methods for forming the nozzle substrate and the liquid-repellent layer are as described above.

[0172] [Laminate] The laminate of the present disclosure has a substrate and a liquid-repellent layer disposed on the substrate, and the liquid-repellent layer includes the structure represented by formula (A) above.

[0173] The preferred embodiment of the substrate is the same as the preferred embodiment of the nozzle substrate. An intermediate layer and a liquid-repellent layer may be laminated in this order on the substrate.

[0174] The laminate of the present disclosure is useful as one component of the inkjet head of the present disclosure.

[0175] [Inkjet Recording Method] The inkjet recording method of the present disclosure includes ejecting an ink from the inkjet head of the present disclosure. Examples of the ink are as described above. It is particularly preferable that the ink contains at least one compound selected from the group consisting of a (meth)acrylate compound and an N-vinyl compound.

[0176] There are no particular limitations on the method of ejecting ink from the inkjet head, and any of the well-known methods may be used, such as a charge control method that uses electrostatic attraction to eject ink, a drop-on-demand method (pressure pulse method) that uses the vibration pressure of a piezoelectric element, an acoustic inkjet method that converts an electric signal into an acoustic beam and irradiates the ink with it, thereby ejecting the ink using radiation pressure, and a thermal inkjet (Bubble Jet (registered trademark)) method that heats the ink to form bubbles and uses the resulting pressure.

[0177] As a method for ejecting ink from an inkjet head, the inkjet recording method described in JP-A-54-059936 is particularly suitable, in which ink subjected to the action of thermal energy undergoes a sudden change in volume, and the ink is ejected from the nozzles by the force caused by this state change. As an inkjet recording method, the method described in paragraphs

[0093] to

[0105] of JP-A-2003-306623 can also be applied.

[0178] Inkjet head methods include the shuttle method, in which a short serial head is scanned across the width of the recording medium to perform recording, and the line method, which uses a line head in which recording elements are arranged to cover the entire area of ​​one side of the recording medium.

[0179] The line method makes it possible to record an image over the entire surface of a recording medium by scanning the recording medium in a direction intersecting the arrangement direction of the recording elements. The line method does not require a transport system such as a carriage that scans a short head, as in the shuttle method. Furthermore, compared to the shuttle method, the line method does not require complex scanning control of the carriage movement and the recording medium, and only the recording medium moves. Therefore, the line method achieves faster image recording than the shuttle method.

[0180] The inkjet head preferably has a resolution of 300 dpi or more. Here, dpi stands for dots per inch, and 1 inch is 2.54 cm. The resolution is more preferably 600 dpi or more, and even more preferably 800 dpi or more.

[0181] The volume of ink droplets ejected from the nozzles of the inkjet head is preferably 1 to 10 pL (picoliters), more preferably 1.5 to 6 pL, from the viewpoint of obtaining a high-resolution image. Furthermore, from the viewpoint of improving image unevenness and continuous gradation, it is also effective to eject droplets of different volumes in combination.

[0182] The thickness of the ink film ejected from the inkjet head onto the recording medium is not particularly limited, but is preferably 1 μm to 20 μm, more preferably 1 μm to 15 μm, and even more preferably 1 μm to 10 μm.

[0183] The amount of ink applied per unit area was 0.1 g / m ２ ~30g / m ２ is preferred, and 1 g / m ２ ~30g / m ２ More preferably, 3 g / m ２ ~25g / m ２ More preferably, 3 g / m ２ ~20g / m ２ The amount of ink applied is calculated using the following method: A 1 m ink is applied to a non-recording medium at a desired dot ratio (the ratio of the area where an image is recorded to the total area calculated as a percentage). ２ An image is recorded with an area of ​​. The mass of the recording medium before and after image recording is measured, and the amount of ink applied is calculated from the mass difference. The amount of ink applied can be changed as desired by setting the dot ratio and adjusting the ink ejection amount of the device.

[0184] [Siloxane Compound] The siloxane compound of the present disclosure is a siloxane compound represented by the following formula (1X) (hereinafter, siloxane compound (1X)).

[0185]

[0186] In formula (1X), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent an alkyl group or -OSiR. ２ ３ is a group, ２ ３ Three R in the group ２ are each independently an alkyl group, and the number of silicon atoms in one molecule of the siloxane compound represented by formula (1X) is 6 or more.

[0187] The siloxane compound (1X) is the aforementioned siloxane compound (1) limited as follows: In other words, in the siloxane compound (1X), each R is an alkyl group or —OSiR ２ ３ The siloxane compound (1X) is limited to a group having a silicon atom number of 6 or more in one molecule. Except for these points, the siloxane compound (1X) is similar to the above-described siloxane compound (1), and preferred embodiments are also similar.

[0188] As described above for the siloxane compound (1), the number of silicon atoms in one molecule of the siloxane compound (1X) being 6 or more means that the number of silicon atoms in the branched siloxane moiety is 5 or more, and at least two of the seven R's are -OSiR. ２ ３ It means that it is a group.

[0189] The following examples of the present disclosure are presented, but the present disclosure is not limited to these examples. Hereinafter, "%" means "% by mass" unless otherwise specified. Hereinafter, siloxane compound (1) may be simply referred to as "compound (1)" (e.g., Tables 1 to 3).

[0190] Synthesis of Compound A1 as Siloxane Compound (1) Compound A1 was synthesized as siloxane compound (1) (i.e., the siloxane compound of the present disclosure). Details are shown below.

[0191] Synthesis of TMS6 silane: 170 mL of ethyl acetate (Kanto Chemical), 6.6 g of ion-exchanged water, and 129 mg of palladium on carbon (Tokyo Chemical Industry Co., Ltd., 5% palladium, approximately 55% water-wet product) were added to a 500 mL three-neck flask and purged with nitrogen. Next, the three-neck flask was heated to 40°C in a water bath, and 42.5 mL of tris(trimethylsiloxy)silane (Tokyo Chemical Industry Co., Ltd.) was added dropwise over 30 minutes. The mixture was stirred at 40°C for 3 hours to carry out the reaction. After the reaction, the palladium on carbon was removed by filtration through Celite. The resulting solution was concentrated under reduced pressure to obtain 34 g of TMS3 silanol (compound shown below) as a colorless, transparent ink.

[0192]

[0193] Next, 34 g of the resulting TMS3 silanol and 90 g of toluene (manufactured by Wako Pure Chemical Industries, Ltd.) were added to a 500 mL three-neck flask, and the three-neck flask was immersed in an ice bath. After confirming that the temperature had dropped below 5°C, 7.62 g of pyridine (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise, and stirring was continued until the temperature returned to below 5°C. Separately, a solution was prepared by adding 23 g of toluene and 4.9 mL of dichloromethylsilane to a dropping funnel. Next, the prepared solution was added dropwise over 30 minutes to the three-neck flask (i.e., the three-neck flask into which pyridine had been added dropwise to TMS3 silanol and toluene and stirred). After the addition was complete, the reaction solution was heated to 40°C and allowed to react for 3 hours. After the reaction, the precipitated solid was filtered off, and the resulting colorless, transparent ink was subjected to a separation operation. This separation operation was repeated twice using 120 mL of ion-exchanged water, and the organic layer was recovered. Magnesium sulfate was added to the organic layer, and the mixture was dehydrated for 30 minutes or more, concentrated under reduced pressure, and then purified by distillation (at a vapor temperature of 110°C under 50 Pa) to obtain 35 g of TMS6 silane (the compound shown below) as a colorless ink.

[0194]

[0195] <Synthesis of Compound A1> 250 g of dehydrated ethanol (manufactured by Wako Pure Chemical Industries, Ltd.) and 44.34 g of 1-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1 L three-neck flask and cooled with ice water under a nitrogen atmosphere. 26.53 g of octenyltrichlorosilane (manufactured by Sigma-Aldrich) was added dropwise thereto so that the internal temperature remained below 10°C. After the dropwise addition was completed, the mixture was stirred at 25°C for 2 hours, and then 500 mL of hexane and 500 mL of distilled water were added, followed by separation and purification three times. The resulting organic layer was concentrated and purified by distillation (vapor temperature 85°C at 50 Pa) to obtain 23.9 g of octenyltriethoxysilane (the compound shown below).

[0196]

[0197] Next, 2.75 g of octenyltriethoxysilane, 15 mL of toluene (manufactured by Wako Pure Chemical Industries, Ltd.), and 10 μL of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (manufactured by Tokyo Chemical Industry Co., Ltd.) were placed in a 100 mL three-neck flask and heated to 45°C under a nitrogen atmosphere. 5.61 g of TMS6 silane was added dropwise thereto so that the internal temperature remained below 50°C, and the mixture was stirred at 45°C for 1 hour. After stirring, the mixture was cooled to room temperature and passed through an activated carbon filter. The solvent was then removed by distillation under reduced pressure, followed by distillation purification (vapor temperature 155°C at 50 Pa) to obtain 1.7 g of Compound A1 below. The NMR results for Compound A1 are as follows: １ H-NMR (400MHz, CDCl ３ ): σ0.19 (m, 57H); 0.42 (m, 2H); 0.53 (m, 2H); 1.13 (t, 9H, J=6.8Hz); 1.10-1.40 (m, 12H); 3.71 (q, 6H, 6.8Hz)

[0198]

[0199] <<Synthesis of Compound A2 as Siloxane Compound (1)>> The following compound A2 as siloxane compound (1) was synthesized in the same manner as in the synthesis of compound A1, except that TMS6 silane was changed to the following TMS4 silane.

[0200]

[0201] <<Synthesis of Compound A3 as Siloxane Compound (1)>> The following compound A3 as siloxane compound (1) was synthesized in the same manner as in the synthesis of compound A1, except that TMS6 silane was changed to tris(trimethylsiloxy)silane.

[0202]

[0203] <<Synthesis of Compound A4 as Siloxane Compound (1)>> Compound A4 below was synthesized in the same manner as compound A1, except that TMS6 silane was changed to 1,1,1,3,5,5,5-heptamethyltrisiloxane.

[0204]

[0205] Synthesis of Compound A5 as Siloxane Compound (1) TMS6-propylamine (the compound shown below) was obtained from allylamine and TMS6-silane by the method described in a paper (Org. Lett., Vol. 4, No. 13, 2002).

[0206]

[0207] Next, 50 mL of heptane (manufactured by Wako Pure Chemical Industries, Ltd.) and 7.25 g of TMS6 propylamine were added to a 100 mL three-neck flask and cooled with ice water under a nitrogen atmosphere. 2.47 g of triethoxy(3-isocyanatopropyl)silane (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise thereto so that the internal temperature remained below 10°C. After completion of the addition, the mixture was stirred at 25°C for 2 hours and then concentrated under reduced pressure to obtain 9.7 g of Compound A5 below as a colorless ink. The NMR results of Compound A-5 are as follows: １ H-NMR (400MHz, CDCl ３ ): σ0.19 (m, 57H); 0.42 (m, 2H); 0.53 (m, 2H); 1.13 (t, 9H, J=6.8Hz); 1. 23 (m, 4H); 3.04 (m, 4H); 3.71 (q, 6H, 6.8Hz); 4.33 (m, 1H); 4.55 (m, 1H)

[0208]

[0209] <<Synthesis of Compound A6, Compound A7, and Compound A8 as Siloxane Compound (1)>> The following Compound A6 (Example 6), Compound A7 (Example 7), and Compound A8 (Example 8) were synthesized as siloxane compounds (1) in the same manner as in the synthesis of Compound A5, except that TMS6 silane was changed to TMS4 silane, tris(trimethylsiloxy)silane, and 1,1,1,3,5,5,5-heptamethyltrisiloxane, respectively.

[0210]

[0211] <Synthesis of Compound A9 as Siloxane Compound (1)> To a 100 mL three-neck flask were added 1.49 g of 5-bromopent-1-ene (Tokyo Chemical Industry Co., Ltd.), 2.78 g of (1,3-dioxoisoindolin-2-yl)potassium (Wako Pure Chemical Industries, Ltd.), 37 mg of tetrabutylammonium iodide (Wako Pure Chemical Industries, Ltd.), and 10 mL of dehydrated THF (Wako Pure Chemical Industries, Ltd.), and the mixture was stirred at reflux temperature under a nitrogen atmosphere for 2 hours to carry out a reaction. After completion of the reaction, 20 mL of toluene and 20 mL of ion-exchanged water were added, and separation and purification were carried out twice. The resulting organic layer was concentrated to obtain 1.94 g of the following white solid (phthalimidopentene).

[0212]

[0213] A 100 mL three-neck flask was charged with 0.86 g of phthalimidopentene, 10 mL of toluene (manufactured by Wako Pure Chemical Industries, Ltd.), and 4 μL of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (manufactured by Tokyo Chemical Industry Co., Ltd.), and heated to 80°C under a nitrogen atmosphere. 2.80 g of TMS6 silane was added dropwise to the flask so that the internal temperature remained at 90°C or lower. After the addition was complete, the mixture was stirred at 80°C for 1 hour, cooled to room temperature, and passed through an activated carbon filter. The solvent was then distilled off under reduced pressure to obtain 3.5 g of the following colorless ink, TMS6 phthalimidopentene.

[0214]

[0215] 3.5 g of TMS6 phthalimidopentene and 20 mL of 2-methylpropanol (manufactured by Wako Pure Chemical Industries, Ltd.) were placed in a 100 mL three-neck flask and stirred at 65°C under a nitrogen atmosphere. 1 mL of hydrazine monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was then added. After stirring at 65°C for 1 hour and cooling to room temperature, 20 mL of hexane and 20 mL of ion-exchanged water were added, and separation and purification were carried out twice. The resulting organic layer was evaporated under reduced pressure and then purified by distillation (vapor temperature 130°C at 50 Pa), yielding 1.2 g of the following TMS6 pentylamine as a colorless ink.

[0216]

[0217] 10 mL of heptane (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.65 g of TMS6 pentylamine were weighed into a 100 mL three-neck flask and cooled with ice water under a nitrogen atmosphere. 0.19 g of triethoxy(3-isocyanatopropyl)silane (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise to the flask so that the internal temperature remained below 10°C. After the addition was complete, the mixture was stirred at 25°C for 2 hours and then concentrated under reduced pressure to obtain 0.82 g of colorless ink (A-9). The NMR results for compound A9 were as follows: １ H-NMR (400Mhz, CDCl ３ ): σ0.19 (m, 57H); 0.42 (m, 2H); 0.53 (m, 2H); 1.13 (t, 9H, J=6.8Hz); 1.23 (m, 4H); 1. 37 (m, 2H); 1.51 (m, 2H); 3.04 (m, 4H); 3.71 (q, 6H, 6.8Hz); 4.33 (m, 1H); 4.55 (m, 1H)

[0218]

[0219] <<Synthesis of Compound A10, Compound A11, and Compound A12 as Siloxane Compound (1)>> The following Compound A10 (Example 10), Compound A11 (Example 11), and Compound A12 (Example 12), each of which is a siloxane compound (1), were synthesized in the same manner as in the synthesis of Compound A9, except that TMS6 silane was changed to TMS4 silane, tris(trimethylsiloxy)silane, and 1,1,1,3,5,5,5-heptamethyltrisiloxane, respectively.

[0220]

[0221] Synthesis of Compounds A13 to A22 as Siloxane Compound (1) The following compounds A13 to A22 were synthesized as siloxane compounds (1) by the same method as in Examples 1 to 12 described above, by appropriately selecting the types of compounds used as raw materials.

[0222]

[0223]

[0224] Example 1 Preparation of Water-Based Ink Ink K1 (black ink) described in paragraph 0270 of JP 2018-35270 A was prepared as a water-based ink for evaluation. The composition of the water-based ink is as follows. The surface tension of the water-based ink at 25°C was 40 mN / m.

[0225] - Composition of water-based ink - Carbon black: 4 parts by mass; Polymer dispersant P-1: 2 parts by mass; Sannix GP-250 (organic solvent manufactured by Sanyo Chemical Industries, Ltd.): 10 parts by mass; Tripropylene glycol monomethyl ether: 5 parts by mass; Olfine E1010 (nonionic surfactant manufactured by Nissin Chemical Industry Co., Ltd.): 1 part by mass; Resin particles (B-01): 8 parts by mass; Water: 70 parts by mass

[0226] The polymer dispersant P-1 is an acrylic resin described in paragraphs 0260 to 0262 of JP 2018-35270 A (specifically, a benzyl methacrylate / methacrylic acid / methyl methacrylate copolymer (copolymerization mass ratio 60 / 10 / 30, weight molecular weight 44,600)). The resin particles (B-01) are particles made of an acrylic resin described in paragraphs 0267 to 0268 of JP 2018-35270 A (specifically, a phenoxyethyl acrylate / methacrylic acid / methyl methacrylate copolymer (copolymerization mass ratio 50 / 5 / 45, weight molecular weight 64,000)).

[0227] <<Preparation of UV Ink>> The UV ink for evaluation was prepared as described in Example 1 of JP 2015-160890 A. The composition of the UV ink was as follows: The surface tension of the UV ink at 25°C was 25 mN / m.

[0228] —Composition of UV ink— 3-methyl-1,5-pentanediol diacrylate (SR341, manufactured by Sartomer; polymerizable compound)... 80 parts by mass DVE-3 (triethylene glycol divinyl ether, manufactured by BASF; polymerizable compound)... 4.1 parts by mass IRGACURE 819 (bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, manufactured by BASF; photopolymerization initiator)... 4 parts by weight of Speedcure 7010 (1,3-di({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl]oxy}acetylpoly[oxy(1-methylethylene)])oxy)-2,2-bis({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl]oxy}acetylpoly[oxy(1-methylethylene)])oxymethyl)propane, manufactured by Lambson, molecular weight 1,899; photopolymerization initiator)... 2 parts by weight of Cyan Millbase A (listed below)... 9.5 parts by weight of UV-22 (IRGASTAB UV22, methylated quinone 10-24%, glycerol, propoxylate and acrylic acid ester 76-90%, manufactured by BASF; polymerization inhibitor)... 0.3 parts by weight of BYK307 (silicone-based surfactant, BYK) Chemie Co., Ltd.) ... 0.1 parts by mass

[0229] The cyan mill base A was prepared by placing 300 parts by mass of IRGALITE BLUE GLVO (cyan pigment, manufactured by BASF Japan Ltd.), 620 parts by mass of SR9003 (PO-modified neopentyl glycol diacrylate, manufactured by Sartomer), and 80 parts by mass of SOLSPERSE 32000 (dispersant manufactured by Lubrizol) in a disperser, Motor Mill M50 (manufactured by Eiger), and dispersing the mixture for 4 hours at a peripheral speed of 9 m / s using zirconia beads having a diameter of 0.65 mm.

[0230] <<Preparation of Inkjet Head (Formation of Liquid-Repellent Layer)>> In order to evaluate the performance of each siloxane compound (1) synthesized above (such as the ability of ink droplets to slide off the film), each siloxane compound (1) was used to form a liquid-repellent layer as a film for evaluation on the nozzle substrate described below. Specifically, an inkjet head having a liquid-repellent layer on the ejection surface side was prepared. Details are provided below.

[0231] <Formation of First Intermediate Layer> A nozzle substrate having nozzles formed therein and a flow path substrate having ink flow paths formed therein were bonded together to prepare a bonded body having the same structure as that shown in FIG. 4 and measuring 35 mm × 25 mm × 1 mm.

[0232] Step (a1): The bonded body was placed in a surface treatment vacuum chamber. After evacuating the vacuum chamber, the atmosphere was replaced with oxygen to generate oxygen plasma. The oxygen plasma irradiation conditions were an output of 30 W, a flow rate of 100 mL / min, and an irradiation time of 30 seconds.

[0233] Step (b1): Formation of a hafnium oxide layer Next, the bonded body after step (a1) is placed in an ALD (Atomic Layer Deposition) chamber, and H ２ O gas was introduced to form hydroxyl groups on the surface of the bonded body. Next, tetrakis(dimethylamino)hafnium (TDMAHf) gas was introduced to react the hydroxyl groups formed on the surface of the bonded body with TDMAHf. After that, excess gas was evacuated. Next, H ２ O gas is introduced to react with TDMAHf and H ２ Then, the excess gas was evacuated. Then, the TDMAHf gas was introduced, evacuated, and H ２ The introduction and exhaust of O gas constituted one cycle, which was repeated until a hafnium oxide layer reached a predetermined thickness (30 nm).

[0234] <Formation of Second Intermediate Layer> Step (c1): The bonded body after the silicon oxide film formation step (b1) is placed in an ALD (Atomic Layer Deposition) chamber, and H ２O gas was introduced to form hydroxyl groups on the surface of the bonded body. Next, tris(dimethylamino)silane (TDMAS) gas was introduced to react the hydroxyl groups formed on the surface of the bonded body with TDMAS. After that, excess gas was evacuated. Next, H ２ O gas is introduced to react with TDMAS and H ２ Then, the excess gas was evacuated. Then, TDMAS gas was introduced, evacuated, and H ２ One cycle of introducing and exhausting O gas was repeated until a predetermined thickness (30 nm) was reached to form a silicon oxide layer.

[0235] <Formation of Liquid-Repellent Layer> Step (d1): Hydrophilization Treatment Next, the bonded body after step (c1) was placed in a vacuum chamber. After evacuating the vacuum chamber, the atmosphere was replaced with oxygen to generate oxygen plasma. The oxygen plasma irradiation conditions were an output of 100 W, a flow rate of 100 mL / min, and an irradiation time of 1 minute.

[0236] Step (e1): Vapor Deposition of Film-Forming Agent A (Vacuum Vapor Deposition Method) Next, the bonded body after step (d1) was placed in a vapor deposition chamber. Next, compound A1, which was the siloxane compound (1) described above, was added to a tungsten boat as film-forming agent A. When the temperature of the tungsten boat reached 70°C, the shutter was opened, and while monitoring the film thickness with a quartz crystal oscillator, the shutter was closed when the film thickness ("A vapor deposition film thickness (nm)" shown in Table 1) reached the value shown in Table 1, and film-forming agent A was vapor-deposited.

[0237] Tables 1 to 3 below show the number of Si (silicon) atoms in the siloxane compound (1) (i.e., in one molecule of the siloxane compound (1)) and "L" in the siloxane compound (1) (i.e., "L" in the formula (1)).

[0238] Step (f1): Storage in a high-temperature, high-humidity environment. Next, to promote the hydrolysis reaction of film-forming agent A and the condensation reaction between the conjugate and film-forming agent A after step (e1), the conjugate was left to stand for 12 hours in an environment with a temperature of 60°C and a humidity of 90%. The contact angle of the formed liquid-repellent layer with water was 60° or greater. The contact angle with water was measured at 25°C using a fully automatic contact angle meter (product name "DM-701", manufactured by Kyowa Interface Science Co., Ltd.).

[0239] Step (g1): Removal of the liquid-repellent layer formed on the inner walls of the nozzles and the ink flow paths. Next, tape was attached to the surface of the nozzle substrate in the assembly after step (f1), and oxygen plasma treatment was performed on the nozzles and ink flow paths from the side of the flow path substrate opposite to the side bonded to the nozzle substrate. This removed the liquid-repellent layer formed on the inner walls of the nozzles and the ink flow paths, while leaving the liquid-repellent layer formed on the surface of the nozzle substrate (i.e., the ejection surface). As a result, an inkjet head equipped with a liquid-repellent layer was obtained.

[0240] <Evaluation> The liquid-repellent layers formed as described above were evaluated as follows. The following evaluations were performed using both water-based ink and UV ink (hereinafter simply referred to as "ink"). The results are shown in Table 1.

[0241] <Droplet Rolling Properties on Liquid-Repellent Layer> First, the rolling angle of ink droplets on the liquid-repellent layer of the inkjet head was measured. The rolling angle was measured using a fully automatic contact angle meter (product name "DM-701", manufactured by Kyowa Interface Science Co., Ltd.) at 25°C. Next, the state of ink remaining on the liquid-repellent layer after measuring the rolling angle was visually observed, and the rolling properties of the droplets on the liquid-repellent layer (i.e., cleanability) were evaluated according to the following evaluation criteria: A: No ink remains B: Ink remains in dots C: Ink remains in lines

[0242] The static contact angle of the ink droplet was measured on the liquid-repellent layer of the inkjet head. The static contact angle of the ink droplet was measured at 25°C using a fully automatic contact angle meter (product name "DM-701", manufactured by Kyowa Interface Science Co., Ltd.). The obtained static contact angle was designated the "pre-wipe contact angle." Next, ink was dropped onto a wiping member (product name "Toraysee", manufactured by Toray Industries, Inc.). The nozzle substrate surface of the inkjet head (i.e., the surface on which the liquid-repellent layer was present) was pressed against the dropped surface at a constant pressure of 40 kPa and slid back and forth. After 10,000 reciprocating strokes, the static contact angle of the ink droplet was measured on the liquid-repellent layer of the inkjet head. The obtained static contact angle was designated the "post-wipe contact angle." The contact angle change rate was calculated using the pre-wipe contact angle and the post-wipe contact angle according to the following formula: Contact angle change rate (%) = {(contact angle before wiping - contact angle after wiping) / contact angle before wiping} x 100 Evaluation criteria are as follows. The smaller the contact angle change rate, the more excellent the wiping resistance. A: The contact angle change rate is less than 20%. B: The contact angle change rate is 20% or more but less than 30%. C: The contact angle change rate is 30% or more.

[0243] Examples 2 to 17 The same procedure as in Example 1 was carried out, except that the type of siloxane compound (1) used as film-forming agent A was changed as shown in Table 1. The results are shown in Tables 1 and 2.

[0244] Comparative Example 1 The same procedure as in Example 101 was carried out, except that the siloxane compound (1) used as the film-forming agent A was replaced with a comparative siloxane compound (specifically, the following compound C1) shown in Table 1. The results are shown in Table 2.

[0245]

[0246] The comparative siloxane compound, compound C1, is a compound that does not contain the branched siloxane moiety of siloxane compound (1). Table 2 also shows the number of Si (silicon) atoms in the comparative siloxane compound (i.e., in one molecule of the comparative siloxane compound) and the type of linking group in the comparative siloxane compound that corresponds to "L" in formula (1).

[0247] Examples 18 to 20 The same procedures as in Example 1 were carried out, except that the vapor-deposited film thickness of A was changed as shown in Table 2, and a step of vapor-depositing film-forming agent B, which was a siloxane compound other than siloxane compound (1) (specifically, compound (B1X-1) below), to a vapor-deposited film thickness of B (nm) shown in Table 2 was added between "step (d1): hydrophilization treatment" and "step (e1): vapor deposition of film-forming agent A." The results are shown in Table 2.

[0248]

[0249] Like compound C1, compound B is a compound that does not contain the branched siloxane moiety of siloxane compound (1). Table 2 also shows the number of Si (silicon) atoms in one molecule of compound B and the type of linking group in compound B that corresponds to "L" in formula (1).

[0250] Examples 21 to 25 The same operations as in Example 101 were carried out, except that "Step (e1): Vapor deposition of film-forming agent A" was changed to a step of forming a liquid-repellent layer by MVD (Molecular Vapor Deposition) using siloxane compound (1) shown in Table 3. The results are shown in Table 3. The liquid-repellent layer was formed by MVD using the method described in JP 2014-166747 A.

[0251]

[0252]

[0253]

[0254] As shown in Tables 1 to 3, the liquid-repellent layers of Examples 1 to 25 formed using Compound (1), which is a siloxane compound of the present disclosure, were superior in terms of droplet rolling-off properties and wipe resistance compared to the liquid-repellent layer of Comparative Example 1 formed using Compound C1, which is a comparative compound.

[0255] In each of Examples 1 to 25, the surface of the liquid-repellent layer was measured by X-ray photoelectron spectroscopy under the following conditions, and the following was found: -OSiCH ３Groups were detected. - Conditions for X-ray photoelectron spectroscopy - The surface of the liquid-repellent layer was measured by X-ray photoelectron spectroscopy using monochromated Al Kα rays as the X-ray source, with F1s, C1s, O1s, N1s, and Si2p as the measurement targets. X-ray photoelectron spectroscopy was performed using a PHI5000 VersaProbe II manufactured by ULVAC-PHI, Inc. The photoelectron take-off angle was set to 45°. During the measurement, charging correction was performed using a neutralization gun.

[0256] -OSiCH detected above ３ The group is a branched siloxane moiety "-SiR(OSiR ３ ) ２ The above results suggest that the liquid-repellent layer contains a siloxane structure (A), which is a residue obtained by removing three Xs from each compound (1) (specifically, compounds A1 to A22).

[0257] Next, in each of Examples 1, 9, 22, and 25, the same operations as in Examples 1, 9, 22, and 25 were performed except that the UV ink was changed to ink A or ink B, each having the following composition. As a result, when either ink A or ink B was used, the same results as the evaluation results for the UV ink in each of Examples 1, 9, 22, and 25 were obtained.

[0258] (Composition of Ink A) Monomer VEEA (71.5-α) parts by weight DPGDA 15 parts by weight Photopolymerization initiator Omnirad 819 3 parts by weight Omnirad TPO-L 5 parts by weight Omnirad DETX 5 parts by weight Polymerization inhibitor FLORSTAB UV12 0.5 parts by weight Pigment dispersion Cyan Millbase A (as described above) 9.5 parts by weight

[0259] (Composition of Ink B) - Monomer - NVC... 20 parts by weight SR339... (36.5 - α) parts by weight SR506... 30 parts by weight - Photopolymerization initiator - Omnirad 819... 3 parts by weight OMNIRAD TPO-L... 5 parts by weight OMNIRAD DETX... 5 parts by weight - Polymerization inhibitor - FLORSTAB UV12... 0.5 parts by weight - Pigment dispersion - Cyan Millbase A as described above... 9.5 parts by weight

[0260] Details of each component in ink A and ink B are as follows. - Monomer - VEEA...2-Propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester DPGDA...Dipropylene Glycol Diacrylate NVC...N-Vinyl caprolactam SR339...2-Phenoxyethyl Acrylate SR506...Isobornyl Acrylate -Photopolymerization initiator- Omnirad 819…Bis(2,4,6-Trimethylbenzoyl)Phenylphosphine Oxide…3 parts by mass OMNIRAD TPO-L…Ethyl(2,4,6-Trimethylbenzoyl)-Phenyl Phosphinat…5 parts by mass OMNIRAD DETX…2,4-Diethylthioxanthone…5 parts by mass -Polymerization inhibitor- FLORSTAB UV12... Tris(N-nitroso-N-phenylhydroxylamine) aluminum salt 20% 2-Phenoxyethyl Acrylate 80%

[0261] The disclosure of Japanese Patent Application No. 2024-145972, filed on August 27, 2024, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A film-forming agent containing a siloxane compound represented by the following formula (1): In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

2. The seven Rs in the formula (1) are each independently an alkyl group or —OSiR ２ ３ is a group, ２ ３ Three R in the group ２ The film-forming agent according to claim 1 , wherein each of the groups is independently an alkyl group.

3. The film-forming agent according to claim 1, wherein L in formula (1) is a divalent linking group consisting of one selected from Group A consisting of an alkylene group, an arylene group, an ether group, an ester group, an amide group, a urea group, and a urethane group, or a divalent linking group consisting of a combination of two or more selected from Group A.

4. The film-forming agent according to claim 1, wherein in said L in said formula (1), the number of atoms present on the path from the silicon atom bonded to one end of said L to the silicon atom bonded to the other end of said L is 8 or more.

5. The film-forming agent according to claim 1, wherein the siloxane compound represented by formula (1) has six or more silicon atoms in one molecule.

6. The film-forming agent according to any one of claims 1 to 5, which is used to form a liquid-repellent layer in an ink-jet head having the liquid-repellent layer.

7. A film comprising a siloxane structure represented by the following formula (A): In formula (A), the three * symbols each represent a bonding position, L represents a divalent linking group, and the seven R symbols each independently represent a monovalent substituent other than a halogen atom.

8. An inkjet head having a liquid-repellent layer which is the film according to claim 7.

9. A method for producing a film, comprising the step of producing a film containing a siloxane structure represented by formula (A) using a siloxane compound represented by formula (1). In formula (1), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom. In formula (A), three *s each represent a bonding position, L represents a divalent linking group, and seven Rs each independently represent a monovalent substituent other than a halogen atom.

10. A siloxane compound represented by the following formula (1X): In formula (1X), three Xs each independently represent an alkoxy group or a halogen atom, L represents a divalent linking group, and seven Rs each independently represent an alkyl group or -OSiR. ２ ３ is a group, ２ ３ Three R in the group ２ are each independently an alkyl group, and the number of silicon atoms in one molecule of the siloxane compound represented by formula (1X) is 6 or more.

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