Curable composition and laminate

Abstract

A curable composition according to the present invention contains a compound represented by formula (1). In formula (1), the R1's each independently represent a hydrogen atom or a monovalent organic group, at least one of the R1's being a group that has a cationically polymerizable group, the R2's and R3's each independently represent a hydrogen atom or a monovalent organic group, and a–d each represent a molar ratio, b and c each independently representing a positive number, and a and d each independently representing 0 or a positive number.

Description

Curable composition and laminate

[0001] This disclosure relates to a curable composition and a laminate.

[0002] Optical components such as displays and lenses have seen increased demand for portability in recent years, in addition to improved functionality. Considering lighter weight and easier processing, glass is increasingly being replaced by resin. Since resin components are generally inferior to glass in terms of hardness, scratch resistance, and stain resistance, their surfaces are coated with hard coatings and other coatings using curable compositions. Traditionally, organic materials such as acryloyl and epoxy have been used as coating agents. However, with the increasing demand for diverse external environments and outdoor use due to portability, these coatings have sometimes lacked sufficient weather resistance and durability.

[0003] To address these weather resistance issues, siloxane-based inorganic or organic-inorganic hybrid coatings based on sol-gel reactions have been proposed. These materials are mainly formed on substrate surfaces by thermosetting and exhibit high hardness and weather resistance not found in organic materials. On the other hand, because they are hard and brittle, they were sometimes unsuitable for applications requiring processability such as cutting, conformability to curved surfaces, or thick film formation.

[0004] Patent documents 1 to 3 are known as conventional curable compositions. Patent document 1 discloses an article comprising a transparent substrate having an anti-reflective structured surface and a sintered coating on the anti-reflective structured surface that includes a porous network of silica nanoparticles, wherein the silica nanoparticles are bonded to adjacent silica nanoparticles, and the structured substrate further comprises a support surface and a moisture barrier layer bonded to the support surface of the structured substrate.

[0005] Patent Document 2 describes a coating solution in which the main component of the film, consisting of an organosilicon compound with an average molecular weight of 270 to 2000, has a content ratio of 80% by mass or more of a partial condensate of ethyl silicate with an average molecular weight of 270 to 2000, is A (mass%), the content of the tetraethoxysilane monomer contained in the main component of the film is B (mass%), and the content of the hydrophobic organic solvent capable of dissolving or dispersing the main component of the film is C (mass%), where 5 ≤ A ≤ 100 (mass%), 90 ≤ A + C ≤ 100 (mass%), B ≤ 90 (mass%), and 40 ≤ B + C (mass%). A method for forming a silica coating film is disclosed, comprising: a coating liquid preparation step of preparing a coating liquid in which the content of perhydropolysilazane in the coating liquid is 2% by mass or less; a coating film formation step of forming a coating film of the coating liquid on the surface of an object to be coated; and a crosslinking polymerization step of bringing water into contact with the coating film of the coating liquid and converting the coating film of the coating liquid into a silica silica coating film by hydrolyzing the partial condensate of the ethyl silicate contained in the coating liquid and causing crosslinking polymerization.

[0006] Furthermore, Patent Document 3 discloses a curable composition characterized by containing an organosilicon compound (C1) obtained by a method comprising the step of hydrolyzing and copolymerizing a silicon compound (A1) represented by the following general formula (3) and a silicon compound (B1) represented by the following general formula (4) in a ratio of 0.3 to 1.8 moles of silicon compound (B1) per mole of silicon compound (A1) under alkaline conditions.

[0007] [In general formula (3), R ０ R is an organic group having a methacryloyl group or an acryloyl group. ０ They may be the same or different, R １ R is an organic group having an alkyl group with 1 to 6 carbon atoms, an aralkyl group with 7 to 10 carbon atoms, or an aryl group with 6 to 10 carbon atoms. １may be the same or different, X is a hydrolyzable group, X may be the same or different, and n is 0 or 1.] SiY １ ４ (4) [In general formula (4), Y １ is a siloxane bond-forming group, Y １ may be the same or different.]]

[0008] Japanese Patent Application Laid-Open No. 2017-223983, Japanese Patent Application Laid-Open No. 2020-169311, International Publication No. WO 2009 / 131038

[0009] Patent Document 1 discloses an antireflection coating including a network of silica nanoparticles, but a sintering step is required for formation, and there is no description or mention of elongation. Patent Document 2 discloses a silica coating using a precursor composed of ethyl silicate and perhydropolysilazane, but there is no description or mention of flexibility or elongation. Patent Document 3 describes a hard coat using an organic-inorganic hybrid material having a radically polymerizable functional group, but there is a concern about curing failure due to oxygen inhibition of radical polymerization, and also a concern about insufficient flexibility.

[0010] The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a curable composition that gives a cured film excellent in breaking elongation and continuous bending resistance, and a laminate including a cured film obtained by curing the curable composition.

[0011] Means for solving the above problems include the following aspects. <1> A curable composition containing a compound represented by the following formula (1).

[0012] In formula (1), R １ each independently represent a hydrogen atom or a monovalent organic group, at least one R １ is a group having a cationically polymerizable group, R ２ and R ３ each independently represent a hydrogen atom or a monovalent organic group, a to d represent molar ratios, b and c each independently represent a positive number, and a and d each independently represent 0 or a positive number.

[0013] <2> The curable composition according to <1>, wherein a is 0 and the value of b / c is 0.1 or more and 20 or less. <3> The curable composition according to <1> or <2>, further comprising inorganic particles with an average particle size of less than 1 μm, and / or a compound represented by formula (2) that is different from the compound of formula (1).

[0014] In formula (2), R ４ ~R ６ Each of the following independently represents a hydrogen atom or a monovalent organic group; f to i represent molar ratios; each of the following independently represents 0 or a positive number; and at least one of f and g represents a positive number.

[0015] <4> The aforementioned R ４ ~R ６ The curable composition according to <3>, wherein at least one of the groups comprises a group selected from the group consisting of a linear and / or branched alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, and a group having a cationic polymerizable group, as the monovalent organic group. <5> The curable composition according to <3> or <4>, further comprising a solvent and a polymerization initiator, wherein the mass ratio of the inorganic particles and / or the compound represented by formula (2) in the curable composition excluding the solvent and the polymerization initiator is 50% by mass or more. <6> The R １ A curable composition according to any one of <1> to <5>, wherein the cationic polymerizable group in comprises an oxetanyl group. <7> At least one R ４ , R ５ or R ６ However, the alkyl group is a linear and / or branched alkyl group having 1 to 6 carbon atoms, and the alkyl group includes a methyl group, an ethyl group, or a propyl group, or at least one R ４ , R ５ or R ６ However, it is a cationic polymerizable group, and the R ４ , R ５ or R ６A curable composition according to any one of <3> to <5>, wherein the cationic polymerizable group in contains an oxetanyl group. <8> A curable composition according to any one of <1> to <7>, further containing an epoxy compound. <9> A curable composition according to any one of <1> to <8>, wherein strain cracks do not occur in the cured film even when a 5% tensile strain is applied to a laminate of a 50 μm thick polyethylene terephthalate film and a 5 μm thick cured film of the curable composition. <10> A curable composition according to any one of <1> to <9>, wherein no fracture is observed even when a laminate of a 50 μm thick polyethylene terephthalate film and a 5 μm thick cured film of the curable composition is continuously bent inward 100,000 times at a bending radius R of 0.5 mm. <11> A curable composition according to any one of <1> to <10>, which is a curable composition for coating. <12> A laminate comprising a cured film obtained by curing a curable composition described in any one of <1> to <11>.

[0016] According to this disclosure, it is possible to provide a curable composition that exhibits excellent elongation at break and continuous bending resistance of the resulting cured film, and a laminate comprising a cured film obtained by curing the curable composition.

[0017] The embodiments for implementing this disclosure will be described in detail below. However, this disclosure is not limited to the embodiments described below. In the embodiments described below, the components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and they do not limit this disclosure. In this specification, numerical ranges indicated using "~" include the numerical values ​​before and after "~" as the minimum and maximum values, respectively. In numerical ranges described stepwise in this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another stepwise numerical range. Also, in numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples. Furthermore, in this specification, a combination of two or more preferred embodiments is a more preferred embodiment.

[0018] In this specification, R in formula (1)１ ~R ３ Each of these may independently have part of its structure substituted with a substituent or halogen atom. For example, R １ ~R ３ Each of these groups may independently have part of its structure substituted with an alkyl group, aryl group, aralkyl group, vinyl group, epoxy group, oxetanyl group, hydroxyl group, amino group, alkylamino group, arylamino group, aralkylamino group, ammonium group, sulfanyl group, isocyanurate group, ureido group, isocyanate group, carboxyl group, acid anhydride group, or halogen atom.

[0019] [Curable Composition] The curable composition according to this disclosure contains a compound represented by the following formula (1).

[0020] In formula (1), R １ Each independently represents a hydrogen atom or a monovalent organic group, and at least one R １ R is a group having a cationic polymerizable group. ２ and R ３ Each of the following independently represents a hydrogen atom or a monovalent organic group; a to d represent molar ratios; b and c independently represent positive numbers; and a and d independently represent 0 or a positive number.

[0021] As described above, conventional curable compositions did not have sufficient flexibility and elongation of their cured products. As a result of diligent research by the present inventors, it has been found that by adopting the above configuration, it is possible to provide a curable composition in which the resulting cured film has excellent break elongation and continuous bending resistance. R in formula (1) １ Since b contains a cationic polymerizable group, and b and c are independently positive numbers, it is estimated that a suitable cross-linked structure can be obtained after curing, and therefore, a cured film with excellent elongation at break and continuous bending resistance can be produced.

[0022] Furthermore, the cured film obtained by curing the curable composition according to this disclosure exhibits excellent hardness and weather resistance. Moreover, the cured film obtained by curing the curable composition according to this disclosure shows excellent flexibility and can be cured with heat or active energy rays, making it possible to obtain a coating layer that can be applied to curved surfaces, and the resulting substrate having the cured film also exhibits excellent processability, such as cutting or bending. As a result, highly durable optical and electronic components such as lenses, displays, optical filters, resists, and encapsulants can be obtained.

[0023] <Compound represented by formula (1)> The curable composition according to this disclosure contains the compound represented by formula (1), which is a silsesquioxane derivative.

[0024] Each constituent unit that may be included in the silsesquioxane derivative used in this disclosure is referred to as constituent units (a) to (d) below.

[0025]

[0026] In the compound represented by formula (1), b and c each independently represent a positive number, and a and d each independently represent 0 or a positive number. In other words, the compound represented by formula (1) includes constituent unit (b) and constituent unit (c) from the constituent units (a) to (d) described above, and may optionally include at least one of constituent units (a) and (d).

[0027] In formula (1), a to d represent the molar ratio of constituent units (a) to (d). In formula (1), a to d represent the relative molar ratio of constituent units (a) to (d) that the compound represented by formula (1) may contain. The molar ratio can be determined, for example, from the NMR (nuclear magnetic resonance) analysis values ​​of the compound represented by formula (1). Alternatively, when the reaction rate of each raw material of the compound represented by formula (1) is known, or when the yield is 100%, it can be determined from the amount of raw material used. For example, the molar ratio of each constituent unit of the compound represented by formula (1) can be determined from the amount of raw material charged in a sample dissolved in deuterated chloroform, etc. １ Perform H-NMR analysis, and if necessary, further analysis will be conducted. ２９The structure may also be calculated by performing Si-NMR analysis. Alternatively, the compound may be decomposed into its constituent units using alkali, etc., and the structure of the original compound represented by equation (1) may be estimated from the ratio of the constituent units. If necessary, known methods such as mass spectrometry and IR (infrared absorption spectroscopy) analysis may be combined to determine the molar ratio of each constituent unit of the compound represented by equation (1).

[0028] Each of the constituent units (b) to (d) in formula (1) may be of only one type or of two or more types. Furthermore, the sequence of elements in formula (1) indicates the composition of the constituent units and does not represent the sequence of elements in the compound represented by formula (1). Therefore, the condensation form of the constituent units in the compound represented by formula (1) does not necessarily have to be in the same sequence as in formula (1).

[0029] The silsesquioxane derivative represented by formula (1) above may include, for example, a complete cage structure, an incomplete cage structure, a ladder structure, a random structure, and a linear structure, and may also include structures that are arbitrarily partially combined from these structures. The details of the constituent units (a) to (d) and other constituent units (e) will be described below.

[0030] (Constituent unit (a)) Constituent unit (a) consists of one silicon atom and O ０．５ This is a Q unit that has four (two as oxygen atoms). Note that a Q unit is defined as having one silicon atom and four O ０．５ It means a unit that has four of these elements.

[0031] The proportion of constituent unit (a) in the compound represented by formula (1) is not particularly limited, but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, when expressed as the ratio of the total molar amount of all constituent units (a) to (d) of the compound represented by formula (1) as follows: a / (a ​​+ b + c + d) × 100 (mol%), it is preferably less than 50 mol%, more preferably less than 20 mol%, even more preferably less than 10 mol%, and it is particularly preferable that it does not contain constituent unit (a).

[0032] (Constituent unit (b)) Constituent unit (b) consists of one silicon atom and O ０．５A T unit is a single-valent organic group (1.5 oxygen atoms) with three oxygen atoms (1.5 oxygen atoms) bonded to a silicon atom. ０．５ It means a unit that has three of these elements.

[0033] R in the compound represented by formula (1) １ This may include one type alone or two or more types. １ Each independently represents a hydrogen atom or a monovalent organic group, and at least one R １ This is a group having a cationic polymerizable group. The monovalent organic group includes a cationic polymerizable group. As the cationic polymerizable group, a cyclic ether group is preferred from the viewpoint of elongation at break and resistance to continuous bending, an epoxy group or an oxetanyl group is more preferred, and an oxetanyl group is particularly preferred. １ If the material contains a cationic polymerizable group, it is preferable, and more preferable, that it contains a group represented by the following formula (5) from the viewpoint of elongation at break and resistance to continuous bending.

[0034]

[0035] In formula (5), R ｂ L represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. １ * represents an alkylene group with 1 to 10 carbon atoms, a cycloalkylene group with 3 to 10 carbon atoms, an arylene group with 6 to 10 carbon atoms, or an aralkylene group with 7 to 12 carbon atoms, n represents 0 or 1, and * represents the bond position with the silicon atom.

[0036] L １The atom is preferably an alkylene group having 1 to 10 carbon atoms or a cycloalkylene group having 3 to 10 carbon atoms, and more preferably an alkylene group having 1 to 10 carbon atoms. The alkylene group having 1 to 10 carbon atoms is preferably an alkylene group having 1 to 6 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms, and even more preferably a propylene group. The alkylene group having 1 to 10 carbon atoms may be linear or branched. The cycloalkylene group having 3 to 10 carbon atoms is preferably a cycloalkylene group having 3 to 6 carbon atoms, and more preferably a cycloalkylene group having 4 to 6 carbon atoms. The cycloalkylene group having 3 to 10 carbon atoms may be branched. ｂ Examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, and hexyl groups, with methyl or ethyl groups being preferred and ethyl groups being more preferred.

[0037] Of the constituent units (b), R １ If a constituent unit having a cationic polymerizable group is defined as constituent unit (b)', and its molar ratio is denoted as b', then the proportion (molar ratio) of constituent unit (b)' to all constituent units (b), i.e., b' / b × 100 (mol%), is not particularly limited, but from the viewpoint of elongation at break and resistance to continuous bending, it is preferably 50 mol% or more, more preferably 80 mol% or more, and particularly preferably 100 mol%.

[0038] Also, R １ Preferably, the group is a hydrogen atom, a saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0039] A saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms may be linear or branched. Preferably, the saturated or unsaturated chain hydrocarbon group having 1 to 10 carbon atoms is a saturated or unsaturated chain hydrocarbon group having 1 to 10 carbon atoms, and more preferably a saturated chain hydrocarbon group having 1 to 10 carbon atoms.

[0040] Examples of saturated chain hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups. From the viewpoint of heat resistance and hardness of the cured product, methyl or ethyl groups are preferred, and methyl groups are more preferred.

[0041] Examples of unsaturated chain hydrocarbon groups having 1 to 10 carbon atoms include vinyl groups, 2-propenyl groups, and ethynyl groups.

[0042] A saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms may be branched. Preferably, the saturated or unsaturated cyclic hydrocarbon group having 4 to 6 carbon atoms is a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms.

[0043] The aryl group having 6 to 20 carbon atoms is preferably an aryl group having 6 to 10 carbon atoms.

[0044] Examples of aryl groups having 6 to 20 carbon atoms include phenyl groups, groups in which one or more hydrogen atoms of a phenyl group are substituted with alkyl groups having 1 to 10 carbon atoms, and naphthyl groups. From the viewpoint of heat resistance and hardness of the cured product, phenyl groups are preferred.

[0045] The aralkyl group having 7 to 20 carbon atoms is preferably an aralkyl group having 7 to 10 carbon atoms.

[0046] Examples of aralkyl groups having 7 to 20 carbon atoms include groups in which one hydrogen atom of an alkyl group having 1 to 10 carbon atoms is substituted with an aryl group such as a phenyl group. Examples include benzyl groups and phenethyl groups, and from the viewpoint of heat resistance and hardness of the cured product, the benzyl group is preferred.

[0047] R １ If a portion of the group in R is substituted with a substituent or halogen atom, １ Examples include 3-glycidoxypropyl group, 2-(3,4-epoxycyclohexyl)ethyl group, 3-(3-ethyloxetan-3-yl)methoxypropyl group, 3-hydroxypropyl group, 3-aminopropyl group, 3-dimethylaminopropyl group, 3-hydroxypropyl group, hydrochloride of 3-aminopropyl group, hydrochloride of 3-dimethylaminopropyl group, p-styryl group, N-2-(aminoethyl)-3-aminopropyl group, N-phenyl-3-aminopropyl group, hydrochloride of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyl group, 3-ureidopropyl group, 3-mercaptopropyl group, 3-isocyanatepropyl group, 3-carboxypropyl group, and 3-chloropropyl group.

[0048] The proportion of constituent unit (b) in the compound represented by formula (1) is not particularly limited, but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, when expressed as the ratio of the total molar amount of all constituent units (a) to (d) of the compound represented by formula (1) as follows: b / (a ​​+ b + c + d) × 100 (mol%), it is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 20 mol% or more, even more preferably 30 mol% to 90 mol%, and particularly preferably 40 mol% to 80 mol%.

[0049] Furthermore, from the viewpoint of elongation at break, resistance to continuous bending, and hardness, the b / c value is preferably 0.1 or higher, more preferably 0.2 to 20, even more preferably 0.5 to 10, even more preferably 1.0 to 2.5, and particularly preferably greater than 1.0 and less than 2.0.

[0050] (Constituent unit (c)) Constituent unit (c) consists of one silicon atom and O ０．５ It has two (one as an oxygen atom) and two R ５ This is a D unit in which O is bonded to a silicon atom. Note that a D unit is defined as one silicon atom bonded to one O ０．５ It means a unit that has two of these elements.

[0051] In the constituent unit (c), R ２ Each of these independently represents a hydrogen atom or a monovalent organic group, and the monovalent organic group includes a cationic polymerizable group. From the viewpoint of elongation at break and resistance to continuous bending, a cyclic ether group is preferred as the cationic polymerizable group, an epoxy group or an oxetanyl group is more preferred, and an oxetanyl group is particularly preferred. ２ If the compound contains a cationic polymerizable group, it is preferable, and more preferable, that it contains a group represented by formula (5) from the viewpoint of elongation at break and resistance to continuous bending. Furthermore, the organic group is preferably a saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. In the constituent unit (c), there are multiple R ２ They may be the same or different from each other. ２ Preferred embodiments of saturated or unsaturated chain hydrocarbon groups having 1 to 20 carbon atoms, saturated or unsaturated cyclic hydrocarbon groups having 3 to 8 carbon atoms, aryl groups having 6 to 20 carbon atoms, and aralkyl groups having 7 to 20 carbon atoms in R １ The preferred embodiments are the same as those for saturated or unsaturated chain hydrocarbon groups having 1 to 20 carbon atoms, saturated or unsaturated cyclic hydrocarbon groups having 3 to 8 carbon atoms, aryl groups having 6 to 20 carbon atoms, and aralkyl groups having 7 to 20 carbon atoms. ２ From the viewpoint of elongation at break and resistance to continuous bending, it is preferably a saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms; more preferably an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms; even more preferably a methyl group, an ethyl group, a propyl group, a phenyl group, or a benzyl group; and particularly preferably a methyl group or a phenyl group.

[0052] From the viewpoint of elongation at break, continuous bending resistance, and hardness, the proportion of constituent unit (c) in the compound represented by formula (1) is preferably 10 mol% to 80 mol%, more preferably 20 mol% to 65 mol%, and particularly preferably 30 mol% to 50 mol%, as expressed by the following formula: c / (a ​​+ b + c + d) × 100 (mol%), relative to the total molar amount of all constituent units (a) to (d) of the compound represented by formula (1). Furthermore, from the viewpoint of elongation at break, continuous bending resistance, and hardness, the proportion of constituent unit (c) in the compound represented by formula (1) is preferably less than the proportion of constituent unit (b).

[0053] (Constituent unit (d)) Constituent unit (d) consists of one silicon atom and O ０．５ It has one (0.5 as an oxygen atom) and three R ３ This is an M-unit in which O is bonded to a silicon atom. Note that an M-unit is defined as one silicon atom bonded to an O ０．５ It means a unit that has one of these elements.

[0054] R ３ Each of these independently represents a hydrogen atom or a monovalent organic group, and the monovalent organic group includes a cationic polymerizable group. From the viewpoint of elongation at break and resistance to continuous bending, a cyclic ether group is preferred as the cationic polymerizable group, an epoxy group or an oxetanyl group is more preferred, and an oxetanyl group is particularly preferred. Furthermore, the organic group is preferably a saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. In the constituent unit (d), there are multiple R ３ They may be the same or different from each other. ３ Preferred embodiments of the cationic polymerizable group in R, and saturated or unsaturated chain hydrocarbon groups having 1 to 20 carbon atoms, saturated or unsaturated cyclic hydrocarbon groups having 3 to 8 carbon atoms, aryl groups having 6 to 20 carbon atoms, and aralkyl groups having 7 to 20 carbon atoms are R ２The preferred embodiments are the same as those for saturated or unsaturated chain hydrocarbon groups having 1 to 20 carbon atoms, saturated or unsaturated cyclic hydrocarbon groups having 3 to 8 carbon atoms, aryl groups having 6 to 20 carbon atoms, and aralkyl groups having 7 to 20 carbon atoms. In the constituent unit (d), multiple R groups exist. ３ They may be the same or different from each other. ３ A preferred embodiment is R in the constituent unit (c). ２ It is similar to that.

[0055] The proportion of constituent unit (d) in the compound represented by formula (1) is preferably 30 mol% or less, more preferably 20 mol% or less, and particularly preferably 10 mol% or less, when expressed as the ratio of the total molar amount of all constituent units (a) to (d) of the compound represented by formula (1) using the following formula: d / (a ​​+ b + c + d) × 100 (mol%), from the viewpoint of elongation at break, resistance to continuous bending, and hardness.

[0056] (Other constituent units (e)) The silsesquioxane derivative represented by formula (1) can further be expressed as a Si-free constituent unit (R ７ O １／２ ) may include (hereinafter also referred to as constituent unit (e)). Here, R ７ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms may be either an aliphatic group or an alicyclic group, and may be either linear or branched. Specific examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, and hexyl groups.

[0057] The constituent unit (e) is an alkoxy group, which is a hydrolyzable group contained in the silicon compound described later, or an alkoxy group produced when an alcohol contained in the reaction solvent substitutes for a hydrolyzable group in the silicon compound, and may remain in the molecule without hydrolysis or polycondensation, or it may be a hydroxyl group that remains in the molecule after hydrolysis without polycondensation.

[0058] There are no particular restrictions on the content of constituent unit (e), but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, for example, if the ratio of the molar amount of constituent unit (e) to the total molar amount of all silicon atoms in the compound represented by formula (1), i.e., the total molar amount of all constituent units (a) to (d), is expressed as the following formula: d / (a ​​+ b + c + d) × 100 (mol%), then it is preferably 0 mol% to 100 mol%, more preferably 1 mol% to 70 mol%, even more preferably 2 mol% to 60 mol%, and particularly preferably 3 mol% to 50 mol%.

[0059] The molar ratio of constituent units (e) is, for example, relative to a sample dissolved in deuterated chloroform, etc. １ Perform H-NMR analysis, and if necessary, further analysis will be conducted. ２９ The calculation may also be performed by Si-NMR analysis. If necessary, known methods such as mass spectrometry and IR (infrared absorption spectroscopy) analysis may be combined to determine the molar ratio of each constituent unit of the compound represented by formula (1). The "HO" present in the compound represented by formula (1) １／２ "That is, the product obtained by reacting silanol with a reaction reagent such as chlorotrimethylsilane, １ H-NMR, ２９ By subjecting the compound represented by formula (1) to known analyses such as Si-NMR and / or IR analysis, the presence of "HO" in the compound can be detected. １／２ The content of " may be calculated. It may also be calculated by performing thermal analysis such as thermogravimetric analysis or differential thermal analysis on the sample. Furthermore, the content of constituent unit (e) may be expressed as mass %, for example, as the ratio of the mass of constituent unit (e) to the total mass of all constituent units (a) to (e) of the compound represented by formula (1).

[0060] The weight-average molecular weight (hereinafter also referred to as "Mw") of the compound represented by formula (1) is not particularly limited and may be, for example, 300 to 50,000, 500 to 25,000, 700 to 20,000, or 1,000 to 15,000. In this disclosure, Mw refers to the value obtained by converting the molecular weight measured by GPC (gel permeation chromatography) using polystyrene as a standard substance. For example, the measurement conditions in the [Examples] described below can be used as the measurement conditions for Mw.

[0061] (Method for producing the compound represented by formula (1)) The compound represented by formula (1) can be produced by known methods. Methods for producing silsesquioxane derivatives are disclosed in detail as methods for producing polysiloxanes in Japanese Patent Publication No. 11-116682, Japanese Patent Publication No. 2000-044689, International Publication No. 2004 / 076534, International Publication No. 2009 / 090916, International Publication No. 2009 / 131038, International Publication No. 2012 / 090707, International Publication No. 2013 / 031798, etc.

[0062] In particular, the method for producing the compound represented by formula (1) is R ｎ Six ｐ Preferably, the process includes a step of hydrolyzing at least one organosilicon compound represented by (n represents an integer from 0 to 3, p represents an integer from 1 to 4, n + p = 4, R represents a hydrogen atom or a monovalent organic group bonded to a silicon atom in the silsesquioxane derivative via a carbon atom, and X represents a hydroxyl group or a hydrolyzable group, with a hydrogenic group being more preferred) using an organic solvent, by adding 0.5 molar equivalents or more of water relative to the total amount of hydrolyzable groups in the organosilicon compound (hereinafter also referred to as the "hydrolysis step"). R is a monovalent organic group bonded to a silicon atom in the silsesquioxane derivative via a carbon atom (R in formula (1) above). １ ~R ３ Examples of suitable components include: X is preferably a hydroxyl group, an alkoxy group, a silyloxy group, or a halogen atom, with an alkoxy group or a silyloxy group being more preferred.

[0063] In the hydrolysis step, it is preferable to perform not only the hydrolysis of the organosilicon compound, but also the hydrolysis and polycondensation reaction of the organosilicon compound and, if necessary, other silicon compounds. Alternatively, in the hydrolysis step, after performing the hydrolysis and polycondensation reaction of the organosilicon compound and, if necessary, other silicon compounds to obtain an intermediate product, a silsesquioxane derivative, the obtained intermediate product may be further subjected to hydrolysis and polycondensation reactions with the organosilicon compound, etc.

[0064] As described above, when obtaining an intermediate product, after hydrolysis and polycondensation reactions of the organosilicon compound and, if necessary, other silicon compounds, the obtained intermediate product may be further subjected to hydrolysis and polycondensation reactions of the organosilicon compound in which n is 3 and p is 1. This makes it possible to suitably synthesize a compound represented by formula (1) in which the terminal portion is sealed with a constituent unit (d) derived from the organosilicon compound in which n is 3 and p is 1, thereby suppressing the viscosity increase of the silsesquioxane derivative and improving storage stability.

[0065] A method for producing the compound represented by formula (1) preferably includes a distillation step in which a silicon compound is subjected to hydrolysis and polycondensation in the presence of a reaction solvent, and then the reaction solvent, by-products, residual monomers, water, etc. are removed from the reaction solution.

[0066] Examples of silicon compounds that yield a constituent unit (a) by hydrolysis, where n is 0 and p is 4, include tetramethoxysilane, tetraethoxysilane, and tetrapropoxysilane.

[0067] Examples of the organosilicon compounds in which n is 1 and p is 3 include those having an oxetanyl group, such as (3-ethyl-3-oxetanylmethoxypropyl)trimethoxysilane, (3-ethyl-3-oxetanylmethoxypropyl)triethoxysilane, (3-methyl-3-oxetanylmethoxypropyl)trimethoxysilane, (3-oxetanyloxypropyl)triethoxysilane, and (3-oxetanylmethoxypropyl)trichlorosilane.

[0068] Examples of the organosilicon compounds in which n is 1 and p is 3 include those having an epoxy group, such as 3-(glycidyloxypropyl)trimethoxysilane, (glycidyloxypropyl)triethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0069] Examples of the organosilicon compounds in which n is 1 and p is 3 include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, octyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, benzyltrimethoxysilane, cyclohexyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, p-styryltrimethoxysilane, ethinyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3- Examples include aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-isocyanatetopropyltriethoxysilane, tris(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropyltrimethoxysilane, (3-acryloyloxypropyl)trimethoxysilane, (3-acryloyloxypropyl)triethoxysilane, (8-acryloyloxyoctyl)trimethoxysilane, (3-acryloyloxypropyl)trichlorosilane, (3-methacryloyloxypropyl)trimethoxysilane, (3-methacryloyloxypropyl)triethoxysilane, and (8-methacryloyloxyoctyl)trimethoxysilane and (3-methacryloyloxypropyl)trichlorosilane.

[0070] Examples of the organosilicon compounds in which n is 2 and p is 2 include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldidiethoxysilane, propylmethyldimethoxysilane, octylmethyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, diphenyldimethoxysilane, benzylmethyldimethoxysilane, cyclohexylmethyldimethoxysilane, vinylmethyldimethoxysilane, allylmethyldimethoxysilane, p-styrylmethyldimethoxysilane, ethinylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and (3-ethyl-3-oxetanylmethoxypropyl)methyldimethoxysilane. Examples include (3-ethyl-3-oxetanylmethoxypropyl)methyldiethoxysilane, (3-methyl-3-oxetanylmethoxypropyl)methyldimethoxysilane, (3-oxetanyloxypropyl)methyldiethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropylmethyldimethoxysilane, hydrochloride salt of N-(vinylbenzyl)-2-aminoethyl-3-aminopropylmethyldimethoxysilane, 3-ureidopropylmethyldialkoxysilane, 3-isocyanatetopropylmethyldiethoxysilane, (3-acryloxypropyl)methyldimethoxysilane, and (3-methacryloxypropyl)methyldiethoxysilane.

[0071] Furthermore, the constituent unit represented by constituent unit (c) can also be introduced as a compound of formula (1) by polycondensation of silicone oligomers. Examples include polydimethylsiloxane with OH type at both ends, polydimethylsiloxane with OH type at one end, polydiphenylsiloxane with OH type at both ends, polydiphenylsiloxane with OH type at one end, polymethylphenylsiloxane with OH type at both ends, and polymethylphenylsiloxane with OH type at one end. There are no restrictions on the molecular weight of these compounds, but for example, their number average molecular weight is preferably 100 to 20,000, more preferably 500 to 10,000, even more preferably 800 to 5,000, and particularly preferably 900 to 3,000.

[0072] Examples of the organosilicon compounds in which n is 3 and p is 1 include hexamethyldisiloxane, trimethylmethoxysilane, trimethylethoxysilane, trimethylchlorosilane, 1,3-divinyltetramethyldisiloxane, dimethylphenylmethoxysilane, vinyldimethylmethoxysilane, 2-(3,4-epoxycyclohexyl)ethyldimethylmethoxysilane, 3-glycidoxypropyldimethylmethoxysilane, (3-ethyl-3-oxetanylmethoxypropyl)dimethylmethoxysilane, (3-ethyl-3-oxetanylmethoxypropyl)dimethylethoxysilane, (3-methyl-3-oxetanylmethoxypropyl)dimethylmethoxysilane, and (3-oxetanyloxypropyl)dimethylethoxysilane.

[0073] In the hydrolysis step, there are no particular limitations on the reaction solvent, but it is preferable to use an alcohol as the organic solvent. An alcohol is an alcohol in the narrow sense, represented by the general formula R-OH, and is a compound that has no functional groups other than an alcoholic hydroxyl group. There are no particular limitations on the alcohol, and examples include methanol, ethanol, 1-propanol, 2-propanol, 2-butanol, 2-pentanol, 3-pentanol, 2-methyl-2-butanol, 3-methyl-2-butanol, cyclopentanol, 2-hexanol, 3-hexanol, 2-methyl-2-pentanol, 3-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-3-pentanol, 2-ethyl-2-butanol, 2,3-dimethyl-2-butanol, and cyclohexanol. Among these, secondary alcohols such as 2-propanol, 2-butanol, 2-pentanol, 3-pentanol, 3-methyl-2-butanol, cyclopentanol, 2-hexanol, 3-hexanol, 3-methyl-2-pentanol, and cyclohexanol are preferred. In the hydrolysis step, one or more of these alcohols may be used in combination.

[0074] The organic solvent used in the hydrolysis process may be alcohol alone, or it may be a mixed solvent with at least one auxiliary solvent. The auxiliary solvent may be a polar solvent, a nonpolar solvent, or a combination of both. Examples of organic solvents other than alcohol include xylene, toluene, methyl ethyl ketone, methyl isobutyl ketone, and propylene glycol monomethyl ether.

[0075] The hydrolysis and condensation reactions in the hydrolysis step proceed in the presence of water. In the hydrolysis step, it is preferable to add 0.5 to 30 molar equivalents of water relative to the total amount of hydrolyzable groups of the organosilicon compound to perform hydrolysis, and then to perform condensation. Furthermore, in the hydrolysis step, from the viewpoint of the hardening shrinkage rate, hardness, and storage stability of the resulting compound represented by formula (1), the amount of water added is preferably 0.6 molar equivalents or more, more preferably 0.7 molar equivalents or more, even more preferably 0.8 to 8 molar equivalents, particularly preferably 0.9 to 7 molar equivalents, and most preferably 1.0 to 6 molar equivalents, relative to the total amount of hydrolyzable groups of the organosilicon compound.

[0076] Furthermore, the hydrolysis and polycondensation reactions of silicon compounds may be carried out without a catalyst or with a catalyst. When a catalyst is used, acid catalysts such as inorganic acids such as sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid; organic acids such as formic acid, acetic acid, oxalic acid, and p-toluenesulfonic acid; and base catalysts such as ammonia, tetramethylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate are preferably used. The amount of catalyst used is preferably equivalent to 0.01 mol% to 20 mol%, and more preferably equivalent to 0.1 mol% to 10 mol%, based on the total amount (moles) of silicon atoms contained in the silicon compound.

[0077] The completion of the hydrolysis and polycondensation reactions in the hydrolysis step can be appropriately detected by methods described in various publications. Furthermore, in the hydrolysis step of the method for producing the compound represented by formula (1), auxiliary agents may be added to the reaction system.

[0078] By including the aforementioned distillation step after the hydrolysis step in the production of the compound represented by formula (1), the stability of the resulting silsesquioxane derivative of the present disclosure can be improved. Distillation can be carried out under atmospheric pressure or reduced pressure, at room temperature or under heating, or under cooling.

[0079] The method for producing the compound represented by formula (1) may include a neutralization step to neutralize the catalyst before the distillation step. It may also include a step to remove the salt produced by neutralization by washing with water or the like.

[0080] Furthermore, the compound represented by formula (1) may contain a ring-opening group formed by the addition of an acid to an oxetanyl group or epoxy group among the side-chain functional groups derived from the silicon compound used as a raw material in its production, or it may contain a hydroxyalkyl group produced by the decomposition of an organic group having a (meth)acryloyl group, or it may contain a group formed by the addition of an acid to an unsaturated hydrocarbon group, etc. Specific examples include, for instance, a compound in which a part of formula (1) contains the structure represented by the following formula (A) and / or the structure represented by formula (B). The content ratio is such that it is acceptable to implement this disclosure if it is 50 mol% or less relative to the amount equivalent to the original organic group having an oxetanyl group or epoxy group, the original organic group having a (meth)acryloyl group, or the original organic group having an unsaturated hydrocarbon group derived from the silicon compound used as a raw material, and is preferably 30 mol% or less, and more preferably 10 mol% or less. In formulas (A) and (B), T units are exemplified, but similar D units, M units, etc., may also be used.

[0081]

[0082]

[0083] The content of the compound represented by formula (1) in the curable composition according to this disclosure is preferably 5% to 95% by mass, more preferably 10% to 95% by mass, and even more preferably 20% to 95% by mass, based on the total solid content of the curable composition, from the viewpoint of elongation at break, resistance to continuous bending, and hardness. In this disclosure, the term "solid content" means components excluding solvents, and liquid components such as low molecular weight components other than solvents are also included in "solid content" in this disclosure. Furthermore, if the composition further contains inorganic particles with an average particle size of less than 1 μm and / or the compound represented by formula (2), as described later, the content of the compound represented by formula (1) in the curable composition according to this disclosure is not particularly limited, but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, it is preferably 5% to 90% by mass, more preferably 10% to 70% by mass, even more preferably 15% to 60% by mass, and particularly preferably 20% to 50% by mass, based on the total solid content of the curable composition.

[0084] <Inorganic particles with an average particle size of less than 1 μm> The curable composition according to this disclosure preferably further contains inorganic particles with an average particle size of less than 1 μm and / or a compound represented by formula (2), and more preferably contains inorganic particles with an average particle size of less than 1 μm, from the viewpoint of elongation at break, resistance to continuous bending, and hardness.

[0085] In this disclosure, the average particle size is the median diameter based on volume unless otherwise specified. The average particle size of the inorganic particles is preferably 500 nm or less, more preferably 100 nm or less, and particularly preferably 5 nm or more and 50 nm or less. In this disclosure, the average particle size of the inorganic particles represents the particle size corresponding to a cumulative 50% by volume from the fine particle side in the volume-based particle size distribution of the inorganic material measured by a particle size distribution analyzer based on laser light diffraction scattering.

[0086] There are no particular restrictions on the material of the inorganic particles, and examples include glass, silica, alumina, mica, ceramics, silicone rubber powder, calcium carbonate, aluminum nitride, carbon powder, kaolin clay, dried clay minerals, and dried diatomaceous earth. Among these, silica particles are preferred as the inorganic particles, and colloidal silica is more preferred.

[0087] Furthermore, the inorganic particles may be surface-treated. In particular, inorganic particles having organic groups on their surface are preferred, inorganic particles having polymerizable groups on their surface are more preferred, and inorganic particles having cationic polymerizable groups on their surface are especially preferred. Examples of non-polymerizable organic groups include groups containing non-polymerizable organic groups such as alkyl groups, aryl groups, and aralkyl groups, with alkyl groups being more preferred. The organic groups may also be reactive groups such as sulfanyl groups, amino groups, ethylenically unsaturated groups, and hydroxyl groups. As cationic polymerizable groups, cyclic ether groups are preferred from the viewpoint of elongation at break and resistance to continuous bending, epoxy groups or oxetanyl groups are more preferred, and epoxy groups are especially preferred. There are no particular limitations on the surface treatment method for the inorganic particles, and known methods can be used. Various commercially available inorganic fillers can also be used. Examples of commercially available colloidal silica include "MEK-EC-2130Y", "MEK-EC-2430Z", "PGM-AC-2140", "MIBK-SD-L", "MEK-AC-5140Z", "PMA-ST", "TOL-ST", "EAC-ST", "MEK-ST-ZL", "MIBK-ST", and "CHO-ST-M" from Nissan Chemical Corporation; "ELCOM V-8804" and "ELCOM V-8802" from JGC Catalysts & Chemicals Corporation; and "NANOBYK-3650", "NANOBYK-3652", "BYK-UV 3518", and "BYK-UV 3519" from BYK Corporation.

[0088] In the curable composition according to the present disclosure, the mass ratio of the inorganic particles in the curable composition excluding the solvent and the polymerization initiator is preferably 5% by mass to 90% by mass, more preferably 15% by mass to 85% by mass, still more preferably 30% by mass to 80% by mass, and particularly preferably 50% by mass to 75% by mass, from the viewpoints of elongation at break, continuous bending resistance and hardness.

[0089] <Compound Represented by Formula (2)> From the viewpoint of hardness, the curable composition according to the present disclosure preferably further includes a compound represented by formula (2). The compound represented by formula (2) is a compound different from the compound represented by formula (1), preferably a compound having a cationically polymerizable group, and preferably a compound having an organic group, wherein both f and g are positive numbers.

[0090] In formula (2), R ４ to R ６ each independently represent a hydrogen atom or a monovalent organic group; f to i each represent a molar ratio, f to i each independently represent 0 or a positive number, and at least one of f and g represents a positive number.

[0091] Each structural unit of the compound represented by formula (2), which is a silsesquioxane derivative, is referred to as structural units (f) to (i), respectively, according to the subscripts f to i at the lower right of the parentheses indicating each structural unit. Preferred embodiments of the structural units (f) to (i) are the same as the preferred embodiments of the structural units (a) to (d), respectively, except as described later. Further, R ４ to R ６ also have the same preferred embodiments as the preferred embodiments of R １ to R ３ , respectively, except as described later.

[0092] From the viewpoints of elongation at break, continuous bending resistance and hardness, it is preferable that at least one of R ４ to R ６ contains a cationically polymerizable group. The cationically polymerizable group is preferably a cyclic ether group, more preferably an epoxy group or an oxetanyl group, and particularly preferably contains an oxetanyl group. R ４ to R６ When at least one of them contains a cationically polymerizable group, it is preferable to include a group represented by the above formula (5), and more preferably a group represented by the above formula (5), from the viewpoints of elongation at break and continuous bending resistance. Further, from the viewpoints of elongation at break, continuous bending resistance and hardness, at least one R ４ is more preferably a cationically polymerizable group.

[0093] R ４ to R ６ When the organic group of is not a polymerizable group, from the viewpoints of elongation at break and continuous bending resistance, it is preferably a saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, a saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms, still more preferably a methyl group, an ethyl group, a propyl group, a phenyl group, or a benzyl group, and a methyl group is particularly preferred.

[0094] The proportion of the structural unit (f) in the compound represented by formula (2) is not particularly limited. From the viewpoints of elongation at break, continuous bending resistance and hardness, when expressed as the following formula based on the total moles of structural units (f) to (i) of the compound represented by formula (2): f / (f+g+h+i)×100 (mol%), it is preferably 0 mol% to 80 mol%, more preferably 0 mol% to 70 mol%, still more preferably 0 mol% to 60 mol%, and particularly preferably 0 mol% to 50 mol%.

[0095] The proportion of constituent units (g) in the compound represented by formula (2) is not particularly limited, but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, when expressed as the ratio of the total molar amount of all constituent units (f) to (i) of the compound represented by formula (2) to the following formula: g / (f + g + h + i) × 100 (mol%), it is preferably 0 mol% to 100 mol%, preferably 30 mol% to 100 mol%, preferably 50 mol% to 100 mol%, more preferably 60 mol% to 100 mol%, even more preferably 70 mol% to 100 mol%, and particularly preferably 80 mol% to 100 mol%.

[0096] From the viewpoint of elongation at break, resistance to continuous bending, and hardness, the proportion of constituent unit (h) in the compound represented by formula (2) is preferably 50 mol% or less, more preferably 30 mol% or less, even more preferably 10 mol% or less, and particularly preferably 0 mol%, when expressed as the ratio of the total molar amount of all constituent units (f) to (i) of the compound represented by formula (2) using the following formula: h / (f+g+h+i) × 100 (mol%).

[0097] From the viewpoint of elongation at break, resistance to continuous bending, and hardness, the proportion of constituent unit (i) in the compound represented by formula (2) is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and particularly preferably 0, i.e., i does not contain constituent unit (i).

[0098] (Other constituent units (j)) The silsesquioxane derivative represented by formula (2) can further be expressed as a Si-free constituent unit (R ８ O １／２ ) may include (hereinafter also referred to as constituent unit (j)). Here, R ８is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms may be either an aliphatic group or an alicyclic group, and may be either linear or branched. Specific examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, and hexyl groups.

[0099] The constituent unit (j) is an alkoxy group, which is a hydrolyzable group contained in the silicon compound described later, or an alkoxy group produced when an alcohol contained in the reaction solvent substitutes for a hydrolyzable group in the silicon compound. It may remain in the molecule without hydrolysis or polycondensation, or it may be a hydroxyl group that remains in the molecule without polycondensation after hydrolysis. The preferred embodiment of constituent unit (j) is the same as the preferred embodiment of constituent unit (e). The content of constituent unit (j) may be calculated in the same manner as that of constituent unit (e).

[0100] The weight-average molecular weight (hereinafter also referred to as "Mw") of the compound represented by formula (2) is not particularly limited and may be, for example, 300 to 50,000, 500 to 25,000, 700 to 20,000, or 1,000 to 15,000. In this disclosure, Mw refers to the value obtained by converting the molecular weight measured by GPC (gel permeation chromatography) using polystyrene as a standard substance. For example, the measurement conditions in the examples described later can be used as the measurement conditions for Mw.

[0101] (Method for producing the compound represented by formula (2)) The compound represented by formula (2) can be produced by known methods, similar to the compound represented by formula (1).

[0102] The compound represented by formula (2) above may include, for example, a complete cage structure, an incomplete cage structure, a ladder structure, a random structure, and a linear structure, and may also include structures that are arbitrarily partially combined from these structures.

[0103] The mass ratio of the compound represented by formula (2) in the curable composition according to this disclosure, excluding the solvent and polymerization initiator, is not particularly limited, but from the viewpoint of elongation at break, resistance to continuous bending, and hardness, it is preferably 10% to 95% by mass, more preferably 30% to 90% by mass, and even more preferably 50% to 85% by mass.

[0104] <Polymerization Initiator> From the viewpoint of curability, the curable composition according to this disclosure preferably contains a polymerization initiator, more preferably a cationic polymerization initiator, and particularly preferably a photocationic polymerization initiator. Known compounds may be used as the polymerization initiator.

[0105] Examples of photocationic polymerization initiators include onium salts such as iodonium salts, sulfonium salts, diazonium salts, selenium salts, pyridinium salts, ferrocenium salts, and phosphonium salts. Among these, iodonium salts or sulfonium salts are preferred. When the photocationic polymerization initiator is an iodonium salt or sulfonium salt, the counter anion is, for example, BF ４ － AsF ６ － SbF ６ － , PF ６ － , B (C ６ F ５ ) ４ － These are some examples.

[0106] The iodonium salts mentioned above include (tricumyl)iodonium tetrakis(pentafluorophenyl)borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis(dodecylphenyl)iodonium hexafluoroantimonate, and bis(dodecylphenyl)iodonium tetraf Examples include ruoborates, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluorophosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroantimonate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrafluoroborate, and 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate. Furthermore, commercially available iodonium salts can also be used, specifically, for example, "UV9380C" (product name) from Mentive Performance Materials Japan, "Bluesil PI2074" (product name) from Elkem Silicones, "WPI-116" (product name) and "WPI-113" (product name) from Fujifilm Wako Pure Chemical Industries, Ltd., "TR-PAG-30201" from Changzhou Strong Electronic Materials, "Omnicat250" from IGM RESINS, and "IK-1" and "IK-1FG" from Sunapro.

[0107] The sulfonium salts include bis[4-(diphenylsulfonio)phenyl]sulfide bishexafluorophosphate, bis[4-(diphenylsulfonio)phenyl]sulfide bishexafluoroantimonate, bis[4-(diphenylsulfonio)phenyl]sulfide bistetrafluoroborate, bis[4-(diphenylsulfonio)phenyl]sulfide tetrakis(pentafluorophenyl)borate, diphenyl-4-(phenylthio)phenylsulfonium hexafluorophosphate, diphenyl-4-(phenylthio)phenylsulfonium hexafluoroantimonate, diphenyl-4-(phenylthio)phenylsulfonium tetrafluoroborate, diphenyl-4-(phenylthio)phenylsulfonium tetrakis(pentafluorophenyl)borate, and Examples include riphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide bishexafluorophosphate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide bishexafluoroantimonate, bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide bistetrafluoroborate, and bis[4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl]sulfide tetrakis(pentafluorophenyl)borate.Furthermore, commercially available sulfonium salts can also be used, specifically, for example, "Cyracure UVI-6990" (product name), "Cyracure UVI-6992" (product name) and "Cyracure UVI-6974" manufactured by Dow Chemical Japan, "ADEKA Optomer SP-150" (product name), "ADEKA Optomer SP-152" (product name), "ADEKA Optomer SP-170" (product name) and "ADEKA Optomer SP-172" (product name) manufactured by ADEKA Corporation, and Fuji Fi Examples include "WPAG-370" (product name) and "WPAG-638" (product name) manufactured by LUMU Wako Pure Chemical Industries, Ltd., and "CPI-100P", "CPI-110P", "CPI-101A", "CPI-200K", "CPI-210S", "CPI-100B(40)", "CPI-110B", "CPI-310B", "CPI-310FG", "VC-1S", "VC-1FG", "CPI-410S", "CPI-410B", and "ES-1B" manufactured by Sunapro Co., Ltd.

[0108] Examples of the diazonium salt include benzenediazonium hexafluoroantimonate, benzenediazonium hexafluorophosphate, and benzenediazonium hexafluoroborate.

[0109] Examples of thermal cationic polymerization initiators include sulfonium salts, phosphonium salts, and quaternary ammonium salts, with sulfonium salts being preferred. An example of a counteranion in a thermal cationic polymerization initiator is AsF ６ － SbF ６ － , PF ６ － , and B(C ６ F ５ ) ４ －Examples of sulfonium salts include triphenylsulfonium boron tetrafluoride, triphenylsulfonium antimony hexafluoride, triphenylsulfonium arsenide hexafluoride, tri(4-methoxyphenyl)sulfonium arsenide hexafluoride, and diphenyl(4-phenylthiophenyl)sulfonium arsenide hexafluoride. Commercially available sulfonium salts can be used, such as "ADEKA Opton CP-66" and "ADEKA Opton CP-77" (product names) from ADEKA Corporation, and "San-Aid SI-60L," "San-Aid SI-80L," and "San-Aid SI-100L" (product names) from Sanshin Chemical Industry Co., Ltd. Examples of phosphonium salts include ethyltriphenylphosphonium antimony hexafluoride and tetrabutylphosphonium antimony hexafluoride. Examples of the quaternary ammonium salts include N,N-dimethyl-N-benzylanilinium hexafluoride antimony, N,N-diethyl-N-benzylanilinium tetrafluoride boron, N,N-dimethyl-N-benzylpyridinium hexafluoride antimony, N,N-diethyl-N-benzylpyridinium trifluoromethanesulfonic acid, N,N-dimethyl-N-(4-methoxybenzyl)pyridinium hexafluoride antimony, N,N-diethyl-N-(4-methoxybenzyl)pyridinium hexafluoride antimony, N,N-diethyl-N-(4-methoxybenzyl)toluidinium hexafluoride antimony, and N,N-dimethyl-N-(4-methoxybenzyl)toluidinium hexafluoride antimony.

[0110] The polymerization initiator may be used alone or in combination of two or more types. From the viewpoint of curability, the content of the polymerization initiator is preferably 0.1 to 15.0 parts by mass, more preferably 0.5 to 10.0 parts by mass, even more preferably 1.0 to 8.0 parts by mass, and particularly preferably 2.0 to 6.0 parts by mass, per 100.0 parts by mass of the curable composition excluding the solvent and polymerization initiator.

[0111] (Other Polymerizable Compounds) The curable composition according to this disclosure preferably contains polymerizable compounds other than the compound represented by formula (1) (hereinafter also referred to as "other polymerizable compounds") from the viewpoint of elongation at break, resistance to continuous bending, and hardness. The other polymerizable compounds are not particularly limited as long as they are compounds that can undergo polymerization reactions in the presence of the compound represented by formula (1) and a polymerization initiator. Examples of other polymerizable compounds include silsesquioxane derivatives other than the compound represented by formula (1) or formula (2), epoxy compounds (compounds having epoxy groups), compounds having oxetanyl groups (oxetanyl group-containing compounds), and compounds having vinyl ether groups (vinyl ether compounds).

[0112] In particular, among the other polymerizable compounds, it is preferable to include a bifunctional polymerizable compound, and more preferably a bifunctional epoxy compound, from the viewpoint of elongation at break, resistance to continuous bending, and hardness.

[0113] Examples of epoxy compounds include monofunctional epoxy compounds and polyfunctional epoxy compounds. Examples of oxetanyl group-containing compounds include monofunctional oxetane compounds and polyfunctional oxetane compounds. Examples of vinyl ether compounds include monofunctional vinyl ether compounds and polyfunctional vinyl ether compounds. As these compounds, for example, compounds described in Japanese Patent Application Publication No. 2011-42755 may be used. There are no particular restrictions on silicones, and known ones can be used, for example, polydimethyl silicone, polydiphenyl silicone and polymethylphenyl silicone, and those having cationic polymerization groups at their terminals and / or side chains are preferred.

[0114] Preferred epoxy compounds include, for example, (3,3',4,4'-diepoxy)bicyclohexyl, dicyclopentadiene diepoxide, and cyclohexene oxide. Also preferred epoxy compounds include, for example, dicyclopentadiene dimethanol, 3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate, epoxidized products of 1,2-epoxy-4-vinylcyclohexane addition polymers of trimethylolpropane, 1,4-cyclohexanedimethanol diglycidyl ether, and dicyclopentadiene dimethanol diglycidyl ether.

[0115] Furthermore, examples of epoxy compounds include 1,4-butanediol diglycidyl ether, 1,2-epoxy-4-(epoxyethyl)cyclohexane, glycerol triglycidyl ether, diethylene glycol diglycidyl ether, 2,6-diglycidylphenyl glycidyl ether, 1,1,3-tris[p-(2,3-epoxypropoxy)phenyl]propane, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, 4,4'-methylenebis(N,N-diglycidylaniline), and 3,4-epoxycyclohexyl. Methyl-3,4-epoxycyclohexanecarboxylate, trimethylolethane triglycidyl ether, triglycidyl-p-aminophenol, tetraglycidyl metaxyldiamine, tetraglycidyl diaminodiphenylmethane, tetraglycidyl-1,3-bisaminomethylcyclohexane, bisphenol-A-diglycidyl ether, bisphenol-S-diglycidyl ether, pentaerythritol tetraglycidyl ether, resorcinol diglycidyl ether, diglycidyl phthalate ester, neopentyl Polyglycol diglycidyl ether, polypropylene glycol diglycidyl ether, tetrabromobisphenol-A-diglycidyl ether, bisphenol hexafluoroacetone diglycidyl ether, pentaerythritol diglycidyl ether, hydrogenated bisphenol-A-diglycidyl ether, tris-(2,3-epoxypropyl) isocyanurate, 1-{2,3-di(propionyloxy)}-3,5-bis(2,3-epoxypropyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-tri 1,3-Bis{2,3-di(propionyloxy)}-5-(2,3-epoxypropyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, monoallyl diglycidyl isocyanurate, diglycerol polydiglycidyl ether, pentaerythritol polyglycidyl ether, 1,4-bis(2,3-epoxypropoxyperfluoroisopropyl)cyclohexane, sorbitol polyglycidyl ether, trimethylolpropane polyglycidyl ether, resorcinol diglycidyl ether, 1,6-Hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, phenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, adipic acid diglycidyl ether, o-phthalate diglycidyl ether, dibromophenyl glycidyl ether, 1,2,7,8-diepoxyoctane, 1,6-dimethylol perfluorohexane diglycidyl ether, 4,4'-bis(2,3-epoxypropoxyperfluoroisopropyl)diphenyl ether, 2,2-bis(4-glycidyloxyphenyl)propane, 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl Examples include hexahexane carboxylate, 3,4-epoxycyclohexyloxirane, 2-(3,4-epoxycyclohexyl)-3',4'-epoxy-1,3-dioxane-5-spirocyclohexane, 1,2-ethylenedioxy-bis(3,4-epoxycyclohexylmethane), 4',5'-epoxy-2'-methylcyclohexylmethyl-4,5-epoxy-2-methylcyclohexane carboxylate, ethylene glycol-bis(3,4-epoxycyclohexane carboxylate), bis-(3,4-epoxycyclohexylmethyl) adipate, and bis(2,3-epoxycyclopentyl) ether.

[0116] In the curable composition according to this disclosure, the mass ratio of the other polymerizable compounds in the curable composition, excluding the solvent and polymerization initiator, is preferably 0% by mass or more and 50% by mass or less, more preferably 1% by mass or more and more preferably 2% by mass or more and more preferably 2% by mass or more and more preferably 30% by mass, from the viewpoint of elongation at break, resistance to continuous bending, and hardness.

[0117] (Other Components) The curable composition according to this disclosure may further contain other components other than the compound represented by formula (1), inorganic particles, the compound represented by formula (2), polymerization initiators, and other polymerizable compounds. The other components are not particularly limited and include, for example, solvents, resins, silicones, monomers, fillers, surfactants, antistatic agents (e.g., conductive polymers), leveling agents, photosensitizers, ultraviolet absorbers, antioxidants, heat resistance improvers, stabilizers, lubricants, pigments, dyes, plasticizers, suspending agents, adhesion promoters, nanoparticles, nanofibers, nanosheets, etc. The curable composition according to this disclosure may also contain silane-based reactive diluents such as tetraalkoxysilanes, trialkoxysilanes, dialkoxysilanes, monoalkoxysilanes, and disiloxanes.

[0118] The curable composition according to this disclosure may or may not contain a solvent. Examples of solvents include various organic solvents such as aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, chlorinated hydrocarbon solvents, alcohol solvents, ether solvents, amide solvents, ketone solvents, ester solvents, and cellosolve solvents.

[0119] (Tensile Strain Resistance of Cured Film) From the viewpoint of elongation at break, resistance to continuous bending, and hardness, it is preferable that the curable composition according to this disclosure does not develop strain cracks in a cured film of 5 μm thickness even when subjected to a tensile strain of 5%. For example, the cured film can be a cured film obtained by curing the curable composition on a substrate such as polyethylene terephthalate (PET) or other plastic.

[0120] The method for measuring the tensile strain resistance of the cured film in this disclosure is as follows: A curable composition prepared as described above is applied to a 50 μm thick PET film (Cosmoshine A4300, manufactured by Toyobo Co., Ltd.) using a bar coater No. 8. After drying the applied curable composition at 60°C for 10 minutes, it is cured by irradiation with ultraviolet light under the following conditions to produce a photocured film. The film thickness is 5 μm. -Ultraviolet irradiation conditions- Lamp: High-pressure mercury lamp (ECS-4011GX, manufactured by I-Graphics Co., Ltd.) Lamp height: 10 cm Conveyor speed: 5.75 m / min Cumulative light intensity per pass: 360 mJ / cm ２ (UV-A, measured using EIT's UVPOWER PUCK II) Ambient: Air Number of passes: 10

[0121] After the photocured film prepared as described above is left to stand for 24 hours in a constant temperature room at 23°C and 50% humidity, it can be stretched using an INSTRON 5965 tensile testing machine (manufactured by INSTRON Japan Co., Ltd.) under the conditions of a measurement temperature of 23°C, a test piece width of 2 cm, and a peeling speed of 10 mm / min to apply a tensile strain of any desired percentage and to check whether or not strain cracks occur in the cured film on the PET substrate. For example, it is possible to check whether or not strain cracks occur in the cured film on the PET substrate by applying a tensile strain of 1% to 26%, and it is preferable that the tensile strain value when no fracture is observed is 5% or more, more preferably 9% or more, even more preferably 11% or more, even more preferably 14% or more, and particularly preferably 20% or more.

[0122] (Breakage resistance of cured film by continuous bending) The curable composition according to this disclosure preferably shows no breakage even when a cured film of the curable composition with a thickness of 5 μm is continuously bent inward 100,000 times at a bending radius R of 0.5 mm. For example, the curable composition according to this disclosure preferably has a cured film thickness of 5 μm or more, more preferably 8 μm or more, even more preferably 10 μm or more, even more preferably 12 μm or more, even more preferably 15 μm or more, and particularly preferably 17 μm or more, when a cured film of the curable composition on a substrate such as a plastic such as PET does not show breakage even when continuously bent inward 100,000 times at a bending radius R of 0.5 mm.

[0123] The method for measuring fracture resistance by continuous bending in this disclosure is as follows: A photocured film is prepared in the same manner as for measuring the tensile strain of a cured film. The photocured film prepared as described above is placed with the hard coat side facing inward in a durability testing machine DMLHP-CS manufactured by Yuasa System Equipment Co., Ltd., and a repeated bending test is performed 100,000 times at a bending radius of 0.5 mm and a speed of 1 time / 2 seconds to check for fracture. The test is performed in a constant temperature and humidity environment set to 23°C and 50% humidity.

[0124] [Cured Film and Laminate] The cured film according to this disclosure is obtained by curing the curable composition according to this disclosure. For example, the cured film according to this disclosure can be obtained by irradiating the curable composition according to this disclosure with active energy rays or by heating the curing composition according to this disclosure. The curable composition according to this disclosure can also be suitably used as a curable composition for coating. The laminate according to this disclosure is a laminate comprising a cured film obtained by curing the curable composition according to this disclosure, and it is preferable that the laminate has a cured film on a substrate.

[0125] When curing the curable composition according to this disclosure, the curable composition according to this disclosure may be applied to a substrate before curing. The curable composition according to this disclosure may or may not contain a solvent. If it contains a solvent, it is preferable to remove the solvent before curing.

[0126] When applying the curable composition according to this disclosure to a substrate, the method of application of the curable composition is not particularly limited. Examples of application methods include conventional coating methods such as inkjet, cast, spin coat, bar coat, dip coat, spray coat, roll coat, flow coat, gravure coat, and vapor deposition. There are no particular limitations on the thickness to which the curable composition according to this disclosure is applied, and it can be set appropriately according to the purpose. There are no particular limitations on the substrate to which the curable composition according to this disclosure is applied, and examples include wood, metal, inorganic materials, plastics, paper, fibers, and fabrics. Examples of metals include copper, silver, iron, aluminum, silicon, silicon steel, and stainless steel. Examples of inorganic materials include metal oxides such as aluminum oxide, silicon oxide, magnesium oxide, zirconium oxide, zinc oxide, indium tin oxide, and gallium oxide; metal nitrides such as aluminum nitride, gallium nitride, and silicon nitride; ceramics such as silicon carbide and boron nitride; mortar, concrete, and glass. Specific examples of plastics include acrylic resins such as polymethyl methacrylate, polyester resins such as polyethylene terephthalate (PET), polyvinyl chloride resin, polycarbonate resin, epoxy resin, polyamide resins such as nylon and aramid, polyimide resin, polyamide-imide resin, fluororesins such as tetrafluoroethylene resin, polyolefin resins such as crosslinked polyethylene resin, vinylidene chloride resin, acrylonitrile-butadiene-styrene (ABS) resin, polystyrene resin, polyacrylonitrile resin, cycloolefin polymer (COP), cycloolefin copolymer (COC), acetate resin, polyarylate, cellophane, norbornene resin, acetylcellulose resin such as triacetylcellulose (TAC), polychloroprene, polyphenylene sulfide, polysulfone, polyethersulfone, polyetheretherketone, polyurethane resin, glass epoxy resin, and other composite resins, as well as various fiber-reinforced resins. Examples of fibers include natural fibers, regenerated fibers, semi-synthetic fibers, metal fibers, glass fibers, carbon fibers, ceramic fibers, and known chemical fibers. The fabric may be woven or nonwoven, and can be made using, for example, the aforementioned fibers.These materials may be used individually, or two or more may be combined, mixed, or compounded. There are no particular restrictions on the shape of the substrate; examples include plate-like, sheet-like, film-like, rod-like, spherical, fibrous, powder-like, lens-like, and other regular or irregular shapes.

[0127] (Curing Method) In this disclosure, the curing method and curing conditions are selected depending on whether the curable composition is active energy ray curable and / or thermosetting. The curing conditions (for example, the type of light source and the amount of light irradiation in the case of active energy ray curable, and the heating temperature and heating time in the case of thermosetting) are appropriately selected depending on the type and amount of polymerization initiator and the types of other polymerizable compounds contained in the curable composition.

[0128] (1) Active Energy Ray Curing Method If the curable composition according to this disclosure is an active energy ray curable composition, the curing method may be to irradiate it with active energy rays using a known active energy ray irradiation device. Examples of active energy rays include electron beams, ultraviolet rays, visible light, and X-rays, with light being preferred and ultraviolet rays being more preferred from the viewpoint of being able to use inexpensive equipment. Examples of ultraviolet irradiation devices include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, ultraviolet (UV) electrodeless lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and light-emitting diodes (LEDs). The light irradiation intensity on a film coated with the curable composition according to this disclosure can be selected according to the purpose, application, etc. The light irradiation intensity in the wavelength range effective for activating the active energy ray polymerization initiator (referred to as the photopolymerization initiator in the case of photocurable) (which varies depending on the type of photopolymerization initiator, but preferably light with a wavelength of 220 nm to 460 nm is used) is 0.1 mW / cm². ２ ~1000mW / cm ２It is preferable that this is the case. Furthermore, the irradiation energy should be appropriately set according to the type of active energy ray, the composition of the mixture, etc. The light irradiation time to the coating may also be selected according to the purpose, application, etc., and the integrated light amount, expressed as the product of the light irradiation intensity and light irradiation time in the light wavelength range, should be 10 mJ / cm. ２ ~7,000mJ / cm ２ It is preferable to set the light irradiation time so that the result is as follows. The integrated light intensity is 200 mJ / cm². ２ ~5,000mJ / cm ２ More preferably, 500 mJ / cm ２ ~4,000mJ / cm ２ This is even more preferable. If the cumulative light intensity is within the above range, the curing of the composition proceeds smoothly, and a uniform cured product can be easily obtained.

[0129] Furthermore, heat curing can be appropriately combined before and / or after active energy ray curing. For example, a two-stage curing process can be performed in which a curable composition is impregnated into a substrate that has areas that are shaded when irradiated with active energy rays, and then the active energy rays are irradiated to first cure the curable composition in the areas that are hit by the active energy rays, and then heat is applied to cure the parts of the composition that are not hit by the active energy rays. There are no particular restrictions on such substrates, and examples include substrates with complex shapes such as fabric, fibers, powder, porous, and uneven surfaces, and may also be shapes that combine two or more of these shapes.

[0130] The cured film according to this disclosure is preferably further heated before or after active energy ray curing. Additional heating provides superior hardness, break elongation, and continuous bending resistance. The heating temperature for the cured film is preferably 60°C to 300°C, more preferably 80°C to 270°C, and even more preferably 100°C to 250°C. The curing temperature may be kept constant or increased. A combination of increasing and decreasing temperature may also be used. The heating time for the cured film is preferably 1 minute to 360 minutes, more preferably 5 minutes to 120 minutes, and even more preferably 5 minutes to 60 minutes.

[0131] (2) Thermosetting Method When the curing composition according to this disclosure is a thermosetting composition, the curing method and curing conditions are not particularly limited. The curing temperature is preferably 80°C to 200°C, more preferably 100°C to 180°C, and even more preferably 110°C to 150°C. The curing temperature may be kept constant or increased. A combination of increasing and decreasing temperature may also be used. The curing time is appropriately selected depending on the type of thermal polymerization initiator and the content ratio of other components, and is preferably 10 minutes to 360 minutes, more preferably 30 minutes to 300 minutes, and even more preferably 60 minutes to 240 minutes. By curing the composition under the above preferred conditions, a uniform cured film without blistering, cracking, etc., can be formed.

[0132] (Applications of Cured Films, etc.) The curable composition according to this disclosure can be used as a variety of coating agents, molding agents, 3D printer compositions, adhesive binders, etc. Because it has excellent hardness in cured products, it can be suitably applied to hard coat films. Furthermore, because the curable composition according to this disclosure has excellent flexibility, it is excellent in microprocessability and thick film formation. For this reason, it can be used as an anti-reflective coating, anti-fouling coating, molding material for 3D printers, resist, imprint material, filler material, planarization material, etc. Furthermore, because it contains polysiloxane and can also contain inorganic fillers as appropriate, it can be used as a gas barrier material, waterproof material, sealing material, corrosion-resistant material, weather-resistant material, heat-resistant material, etc. Also, by curing the curable composition according to this disclosure, a hard coat film with excellent continuous bending resistance, various surface coating films, sealants, adhesives, imprint materials, and resist films with excellent impact resistance and durability can be obtained. The curable composition according to this disclosure may be provided on a substrate, for example, by curing a curable composition applied to a substrate, a substrate with a hard coat film or a resist film can be obtained. The curable composition according to this disclosure may contain various components as needed. A substrate equipped with the cured film according to this disclosure has excellent continuous bending resistance and is therefore suitably used in flexible devices such as foldable devices and rollable devices, displays such as electronic paper, foldable flexible displays, and touch panels, and optical components such as lenses. Furthermore, due to its excellent flexibility, it is suitably used in electronic components such as resists and sealants that exhibit excellent durability, such as resistance to cracking. Examples of applications include works of art and crafts, sanitary ware products such as toilets, painted parts such as automobile and railway vehicle bodies, home appliances, and housing products, where coating can impart abrasion resistance and durability.

[0133] Next, the present disclosure will be described in detail based on examples and comparative examples. The present disclosure is not limited to the following examples.

[0134] <Synthesis of Silsesquioxane Derivatives> (Synthesis Example 1: Synthesis of Silsesquioxane Derivative 1 (compound represented by formula (2))) 83.5 g (0.3 mol) of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane and 75.0 g of 2-propanol were weighed into a 300 mL four-necked flask. In addition, a mixture of 2.7 g (7.5 mmol) of 25% by mass tetramethylammonium hydroxide (TMAH) aqueous solution and 14.2 g (0.9 mol) of water was weighed into a dropping funnel. The TMAH aqueous solution was added dropwise from the dropping funnel while stirring, and then the reaction mixture was neutralized with 8.1 g (4 mmol) of 5% sulfuric acid aqueous solution, and the solvent was removed under reduced pressure. Ether was mixed into the obtained solution and washed with water using a separatory funnel. The organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed under reduced pressure to obtain 60 g of silsesquioxane derivative 1.

[0135] (Synthesis Example 2: Synthesis of Silsesquioxane Derivative 2 (Compound represented by Formula (1))) 167.05 g (0.6 mol) of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane, 50.49 g (0.42 mol) of dimethoxydimethylsilane, and 61.03 g of 2-propanol were weighed into a 500 mL four-necked flask fitted with a stirrer and dropping funnel, and stirred at room temperature. To this mixture, a mixed aqueous solution of 1.07 g (102.7 mmol) of 35% hydrochloric acid aqueous solution and 46.98 g of pure water was added dropwise and reacted. By removing solvents and other substances under reduced pressure from the resulting solution, 156.95 g of silsesquioxane derivative 2 was obtained. １ We measured the 1H-NMR spectrum and confirmed that the T and D units were introduced according to the raw material fermentation ratio.

[0136] (Synthesis Example 3: Synthesis of Silsesquioxane Derivative 3 (Compound represented by Formula (1))) 97.45 g of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane, 18.32 g of OH-type polydimethylsiloxane (functional group equivalent 500 g / mol, number average molecular weight 1,000), and 174.91 g of 2-propanol were weighed out, and a mixture of 3.33 g of 25% TMAH aqueous solution and 16.42 g of water was weighed into a dropping funnel. The silsesquioxane derivative was synthesized in the same manner as in Synthesis Example 1. The 1H-NMR spectrum of the product was measured to confirm that T units and D units were introduced according to the starting material ratio. 12.26 g of the silsesquioxane derivative synthesized in this way was weighed into a 300 mL four-necked flask, and 80 mL of xylene was added. In an ice bath, 14.33 mL (0.08 mol) of pyridine and 10.15 mL of chlorotrimethylsilane were added in sequence, and the mixture was stirred at 80°C for 2 hours. After that, pure water was added to stop the reaction. The resulting mixture was washed with water in a separatory funnel, and the solvent was removed from the resulting xylene solution under reduced pressure to obtain 14 g of silsesquioxane derivative 3. １ 1H-NMR spectra were measured, and the composition ratios in T, D, and M units were determined.

[0137] (Synthesis Example 4: Synthesis of Silsesquioxane Derivative 4 (Compound represented by Formula (1))) Except for using 50.11 g (0.18 mol) of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane and 29.32 g (0.12 mol) of diphenyldimethoxysilane as silane starting materials, 41 g of silsesquioxane derivative 4 was obtained in the same manner as in Synthesis Example 1. １ We measured the 1H-NMR spectrum and confirmed that the T and D units were introduced according to the raw material fermentation ratio.

[0138] (Synthesis Example 5: Synthesis of Silsesquioxane Derivative 5 (Silsesquioxane Compound Having a Radical Polymerizable Group)) Except for using 70.3 g (0.3 mol) of 3-acryloyloxypropyltrimethoxysilane as the silane starting material, 50 g of silsesquioxane derivative 5 was obtained in the same manner as in Synthesis Example 1.

[0139] (Synthesis Example 6: Synthesis of Silsesquioxane Derivative 6 (Silsesquioxane Compound Having a Radical Polymerizable Group)) 38 g of silsesquioxane derivative 6 was obtained in the same manner as in Synthesis Example 1, except that 42.2 g (0.18 mol) of 3-acryloyloxypropyltrimethoxysilane and 14.4 g (0.12 mol) of dimethoxydimethylsilane were used as silane starting materials. １ We measured the 1H-NMR spectrum and confirmed that the T and D units were introduced according to the raw material fermentation ratio.

[0140] The detailed structures of the silsesquioxane derivatives prepared in each synthesis example are shown in Table 1 below. Note that b1, b2, c1, c2, and d1 represent molar ratios, Me represents a methyl group, and Ph represents a phenyl group.

[0141]

[0142] <Preparation of Curable Composition> (Example 1) A curable composition was prepared by adding 0.81 parts by mass of silsesquioxane derivative 1 obtained in Synthesis Example 1, 0.09 parts by mass of silsesquioxane derivative 2 obtained in Synthesis Example 2, 0.10 parts by mass of Celoxide 2021P manufactured by Daicel Corporation, 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl) borate, and 1 part by mass of propylene glycol monobutyl ether to the mixture and stirring the mixture in a rotary-orbit mixer.

[0143] (Examples 2-8) Each component was added to obtain the composition shown in Table 2. Additionally, 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl) borate and 1 part by mass of propylene glycol monobutyl ether were added to 1 part by mass of the solution of the added compound, and the mixture was stirred in a rotary-orbit mixer to prepare each curable composition.

[0144] (Example 9) To 2.03 parts by mass (0.63 parts by mass of solids) of MEK-EC-2430Z (solids concentration 31%) manufactured by Nissan Chemical Corporation, 0.27 parts by mass of silsesquioxane derivative 2 obtained in Synthesis Example 2, 0.10 parts by mass of celoxide 2021P, and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl) borate were added, and the mixture was stirred in a rotary-orbit mixer to prepare a curable composition.

[0145] (Examples 10-13) Each curable composition was prepared by adding each component to achieve the composition shown in Table 3, and adding 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl) borate for every 1 part by mass of the solid content of the added component, and stirring the mixture in a rotary-orbit mixer.

[0146] (Example 14) To 1.94 parts by mass (0.70 parts by mass of solids) of MEK-EC-2130Y (solids concentration 36%) manufactured by Nissan Chemical Corporation, 0.25 parts by mass of silsesquioxane derivative 2 obtained in Synthesis Example 2, 0.05 parts by mass of celoxide 2021P, and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl) borate were added, and the mixture was stirred in a rotary-orbit mixer to prepare a curable composition.

[0147] (Examples 15-17) Each curable composition was prepared by adding each component to achieve the composition shown in Table 3, and adding 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate for every 1 part by mass of the solid content of the added component, and stirring the mixture in a rotary-orbit mixer.

[0148] (Comparative Example 1) A curable composition was prepared by adding 0.9 parts by mass of silsesquioxane derivative 1 obtained in Synthesis Example 1, 0.1 parts by mass of celoxide 2021P, 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate, and 1 part by mass of propylene glycol monobutyl ether to the mixture and stirring the mixture in a rotary-orbit mixer.

[0149] (Comparative Example 2) A curable composition was prepared by adding 0.05 parts by mass of 1-hydroxycyclohexylphenyl ketone and 1 part by mass of propylene glycol monobutyl ether to 1 part by mass of the silsesquioxane derivative 5 obtained in Synthesis Example 5, and stirring the mixture in a rotary-orbit mixer.

[0150] (Comparative Examples 3-5) Each curable composition was prepared by adding each component to achieve the composition shown in Table 2, and by adding 0.05 parts by mass of 1-hydroxycyclohexylphenyl ketone and 1 part by mass of propylene glycol monobutyl ether to 1 part by mass of the solution of the added compound, and stirring the mixture in a rotary-orbit mixer.

[0151] (Comparative Example 6) To 3.06 parts by mass (0.95 parts by mass of solids) of MEK-EC-2430Z (solids concentration 31%) manufactured by Nissan Chemical Corporation, 0.05 parts by mass of celloxide 2021P and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate were added, and the mixture was stirred in a rotary-orbit mixer to prepare each curable composition.

[0152] (Comparative Example 7) Each curable composition was prepared by adding 0.05 parts by mass of celloxide 2021P and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate to 2.64 parts by mass (0.95 parts by mass of solids) of MEK-EC-2130Y (solids concentration 36%) manufactured by Nissan Chemical Corporation, and stirring the mixture in a rotary-orbit mixer.

[0153] (Comparative Example 8) A curable composition was prepared by adding 0.05 parts by mass of 1-hydroxycyclohexylphenyl ketone to 4.0 parts by mass (1.0 part by mass of solids) of JGC Catalysts & Chemicals Co., Ltd. V-8804 (solid content concentration 40%), and stirring the mixture in a rotary-orbit mixer.

[0154] (Comparative Examples 9 and 10) Each curable composition was prepared by adding each component to achieve the composition shown in Table 3, and by adding 0.05 parts by mass of 1-hydroxycyclohexylphenyl ketone for every 1 part by mass of the solid content of the added component, and stirring the mixture in a rotary-orbit mixer.

[0155] <Preparation of Photocurable Films> Each curable composition prepared as described above was applied to a 50 μm thick PET film (Cosmoshine A4300, manufactured by Toyobo Co., Ltd.). For evaluation of pencil hardness, elongation at break, and contact angle measurement, each curable composition was applied using a bar coater No. 8, dried at 60°C for 10 minutes, and then cured by irradiation with ultraviolet light under the following conditions to produce a photocurable film. The film thickness was approximately 5 μm. For evaluation of continuous bending resistance, each curable composition was applied using bar coaters No. 3 to No. 32, dried at 60°C for 10 minutes, and then cured by irradiation with ultraviolet light under the following conditions to produce a photocurable film. The film thickness was approximately 2 μm to 25 μm. - UV Irradiation Conditions - Lamp: High-pressure mercury lamp (ECS-4011GX manufactured by iGraphics Co., Ltd.) Lamp height: 10 cm Conveyor speed: 5.75 m / min Cumulative light intensity per pass: 360 mJ / cm ２ (UV-A, measured using EIT's UVPOWER PUCKII) Atmosphere: Examples 1-13 and Comparative Examples 1, 6 and 7 were in air, while Comparative Examples 2-5 and 8-10 were in nitrogen. Number of passes: 10

[0156] <Evaluation of Pencil Hardness> The photocured film prepared as described above was left to stand for 24 hours in a constant temperature room at 23°C and 50% humidity, and the pencil hardness of the surface was measured in accordance with JIS K5600-5-4. Note that 10B is the softest pencil, and the hardness increases in the order of 9B to B, HB, F, H to 10H.

[0157] <Evaluation of Elongation at Breaking> The photocured film prepared as described above was left to stand for 24 hours in a constant temperature room at 23°C and 50% humidity. Then, it was stretched using an INSTRON 5965 tensile testing machine (manufactured by INSTRON Japan Co., Ltd.) under the conditions of a measurement temperature of 23°C, a test piece width of 2 cm, and a peeling speed of 10 mm / min, and the breaking point at which a strain crack occurred in the cured film on the PET substrate was measured.

[0158] <Contact Angle Measurement> The contact angle of the photocured film prepared as described above with pure water at 23°C was evaluated using DMo-502 manufactured by Kyowa Interface Science Co., Ltd.

[0159] <Evaluation of Continuous Bending Resistance> The light-cured film prepared as described above was placed with the hard coat side facing inward in a Yuasa System Equipment Co., Ltd. DMLHP-CS durability tester, and a repeated bending test was performed 100,000 times at a bending radius of 0.5 mm and a speed of 1 time / 2 seconds. The maximum thickness of the cured film at which no cracks were observed in the hard coat layer after 100,000 times was defined as the bending resistance and is shown in Tables 2 and 3. The test was conducted in a constant temperature and humidity environment set to 23°C and 50% humidity.

[0160]

[0161]

[0162] As shown in Tables 2 and 3, the curable compositions of Examples 1 to 17 all exhibited superior elongation at break of the resulting cured films compared to Comparative Examples 1 to 10. Furthermore, they also exhibited superior resistance to continuous bending. Examples 1 to 17 all contained the compound represented by formula (1), and all had an organic group having an oxetanyl group, which is a cationic polymerizable group, as a polymerizable group. On the other hand, it was found that a cationic polymerizable group is not necessarily required on the surface of the inorganic filler that is suitably blended to increase hardness; for example, a non-polymerizable hydrocarbon group such as an alkyl group may also be used. From this, it can be seen that the organic group of the compound represented by formula (2) may also consist only of a non-polymerizable organic group.

[0163] The disclosure of Japanese Patent Application No. 2025-32248, filed on 28 February 2025, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

Claims

1. A curable composition containing a compound represented by the following formula (1). In formula (1), R １ Each independently represents a hydrogen atom or a monovalent organic group, and at least one R １ R is a group having a cationic polymerizable group. ２ and R ３ Each of the following independently represents a hydrogen atom or a monovalent organic group; a to d represent molar ratios; b and c independently represent positive numbers; and a and d independently represent 0 or a positive number.

2. The curable composition according to claim 1, wherein a is 0 and the value of b / c is 0.1 or more and 20 or less.

3. The curable composition according to claim 1, further comprising inorganic particles with an average particle size of less than 1 μm, and / or a compound represented by formula (2) that is different from the compound of formula (1). In formula (2), R ４ ~R ６ Each of the following independently represents a hydrogen atom or a monovalent organic group; f to i represent molar ratios; each of the following independently represents 0 or a positive number; and at least one of f and g represents a positive number.

4. The aforementioned R ４ ~R ６ The curable composition according to claim 3, wherein at least one of the groups comprises a group selected from the group consisting of a linear and / or branched alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, and a group having a cationic polymerizable group, as the monovalent organic group.

5. The curable composition according to claim 3, further comprising a solvent and a polymerization initiator, wherein the mass ratio of the inorganic particles and / or the compound represented by formula (2) in the curable composition excluding the solvent and the polymerization initiator is 50% by mass or more.

6. The aforementioned R １ The curable composition according to claim 1, wherein the cationically polymerizable group in comprises an oxetanyl group.

7. At least one R ４ , R ５ or R ６ However, the alkyl group is a linear and / or branched alkyl group having 1 to 6 carbon atoms, and the alkyl group includes a methyl group, an ethyl group, or a propyl group, or at least one R ４ , R ５ or R ６ However, it is a cationic polymerizable group, and the R ４ , R ５ or R ６ The curable composition according to claim 3, wherein the cationic polymerizable group in the composition contains an oxetanyl group.

8. The curable composition according to claim 1, further comprising an epoxy compound.

9. The curable composition according to claim 1, wherein strain cracks do not occur in the cured film even when a 5% tensile strain is applied to a laminate of a 50 μm thick polyethylene terephthalate film and a 5 μm thick cured film of the curable composition.

10. The curable composition according to claim 1, wherein a laminate of a 50 μm thick polyethylene terephthalate film and a 5 μm thick cured film of the curable composition shows no breakage even after 100,000 continuous inward bends at a bending radius R of 0.5 mm.

11. The curable composition according to claim 1, which is a curable composition for coating.

12. A laminate comprising a cured film obtained by curing a curable composition according to any one of claims 1 to 11.

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