Coating composition, coat film, and base material

Abstract

The present invention provides: a coating composition containing a compound represented by formula (1); a coat film obtained by curing the coating composition; and a base material comprising the coat film. In formula (1), R1-R3 each independently represent a hydrogen atom or a monovalent organic group, a-d represent molar ratios, a and b each independently represent a positive number, and c and d each independently represent 0 or a positive number.

Description

Coating composition, coating film, and substrate

[0001] The present disclosure relates to a coating composition, a coated film, and a substrate.

[0002] Flexible devices, such as foldable devices and rollable devices, are becoming more common. The displays of these devices require flexibility, transparency, surface hardness, and other properties. When a plastic film is used in a flexible display, a coating film layer with high surface hardness is often provided to prevent scratches. Ultra-thin glass, which is highly hard and bendable, is sometimes used as the substrate. In this case, a coating film layer is also provided to maintain surface hardness and prevent cracking or shattering upon impact.

[0003] The shapes of foldable displays include, for example, an infold shape (inward bending) where the coated film surface is on the inside, an outfold shape (outward bending) where the coated film surface is on the outside, and a tri-fold shape where the coated film surface is on both the inside and outside (Z-folded).

[0004] Examples of coating compositions with high surface hardness include acrylates, epoxy resins, and silsesquioxane derivatives. In addition to various resin films, tempered glass is sometimes used as a substrate. In the case of tempered glass, cationic or anionic curing systems may inhibit polymerization and therefore cannot be used.

[0005] Several conventional coating compositions have been disclosed that produce cured films that are both highly scratch-resistant and flexible. Patent Document 1 discloses a flexible film comprising a substrate, a coating film layer, and an scratch-resistant layer. Patent Document 2 discloses a scratch-resistant coating using a silsesquioxane compound formed by the reaction of a polymerizable functional group with an active hydrogen atom. Patent Document 3 discloses a scratch-resistant coating containing a cationically polymerizable compound and a radically polymerizable compound.

[0006] JP 2023-113598 A International Publication No. 2021 / 060055 International Publication No. 2019 / 146659

[0007] Patent Document 1 describes excellent scratch resistance and flexibility, but achieving this requires sequential application of at least two types of coating, which raises concerns about the complicated process and the tendency toward thick films. Furthermore, the outermost surface contains a fluorine-containing compound, which can make processing to upper layers difficult due to its low surface free energy, and there are also concerns about environmental impact. The invention described in Patent Document 2 can withstand continuous bending at a bending radius of 2 mm, but its scratch resistance is limited to a load of 200 g, which can sometimes result in insufficient scratch resistance. Furthermore, the outermost surface contains a fluorine-containing compound, which can make processing to upper layers difficult due to its low surface free energy, and there are also concerns about environmental impact. The invention described in Patent Document 3 was evaluated at a bending radius of 2.5 mm, raising concerns about its inapplicability to thin modules.

[0008] The present disclosure has been made in view of the above, and aims to provide a coating composition that provides a coating film having excellent scratch resistance, a coating film obtained by curing the coating composition, and a substrate provided with the coating film.

[0009] The means for solving the above problems include the following aspects: <1> A coating composition containing a compound represented by the following formula (1):

[0010]

[0011] In formula (1), R １ ~R ３ each independently represents a hydrogen atom or a monovalent organic group, a to d represent a molar ratio, a and b each independently represent a positive number, and c and d each independently represent 0 or a positive number.

[0012] <2> The R １contains a group having a polymerizable functional group and satisfies 0.4<a / b<1.5. <3> The coating composition according to <1> or <2>, which is capable of forming a film having an average indentation hardness of 0.40 GPa or more at a surface depth of 200 nm to 400 nm measured with a nanoindenter. <4> The coating composition according to any one of <1> to <3>, further containing inorganic particles and a polymerization initiator. <5> The coating composition according to <4>, in which the inorganic particles have an average particle size of less than 1 μm. <6> The coating composition according to <4> or <5>, in which the inorganic particles are silica particles. <7> The coating composition according to any one of <4> to <6>, in which the inorganic particles account for 50 mass% or less of the coating composition excluding the solvent and the polymerization initiator. <8> The coating composition according to any one of <1> to <7>, further comprising a difunctional or higher functional (meth)acrylate compound or a difunctional or higher functional epoxy compound. <9> The coating composition according to <8>, wherein the mass ratio of the difunctional or higher functional (meth)acrylate compound or the difunctional or higher functional epoxy compound in the coating composition excluding the solvent and the polymerization initiator is more than 0 mass% and less than 35 mass%. <10> The coating composition according to any one of <1> to <9>, wherein a film of less than 10 μm in thickness obtained by curing the coating composition does not break even after 200,000 consecutive inward bending cycles with a bending radius R of 1.5 mm. <11> A coating film obtained by curing the coating composition according to any one of <1> to <10>. <12> A substrate having the coating film according to <11>.

[0013] According to the present disclosure, it is possible to provide a coating composition that provides a coating film with excellent scratch resistance, a coating film obtained by curing the coating composition, and a substrate provided with the coating film.

[0014] Hereinafter, embodiments for carrying out the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In the following embodiments, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure. In this specification, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In addition, in numerical ranges described in this specification, the upper or lower limit value of that numerical range may be replaced with a value shown in an example. In this specification, a combination of two or more preferred aspects is a more preferred aspect.

[0015] In this specification, R in formula (1) １ ~R ３ may each independently be partially substituted with a substituent or a halogen atom. １ ~R ３ may each independently be partially substituted in the structure with an alkyl group, an aryl group, an aralkyl group, a vinyl group, an epoxy group, an oxetanyl group, a hydroxyl group, an amino group, an alkylamino group, an arylamino group, an aralkylamino group, an ammonium group, a thiol group, an isocyanurate group, a ureido group, an isocyanate group, a carboxy group, an acid anhydride group, or a halogen atom.

[0016] [Coating Composition] The coating composition according to the present disclosure is a coating composition containing a compound represented by the following formula (1).

[0017]

[0018] In formula (1), R １ ~R ３ each independently represents a hydrogen atom or a monovalent organic group, a to d represent a molar ratio, a and b each independently represent a positive number, and c and d each independently represent 0 or a positive number.

[0019] As described above, conventional coating compositions have insufficient scratch resistance when cured. As a result of intensive research, the present inventors have found that by adopting the above-described configuration, it is possible to provide a coating composition in which the resulting coating film has excellent scratch resistance. It is presumed that when a and b in the above formula (1) are positive numbers, an appropriate crosslinked structure can be obtained after curing, and therefore a coating film with excellent scratch resistance can be produced.

[0020] Furthermore, the coating film obtained by curing the coating composition according to the present disclosure is also excellent in continuous flex resistance. Furthermore, the coating film obtained by curing the coating composition according to the present disclosure is also excellent in hardness while maintaining the continuous flex resistance. Therefore, a display or lens having high durability can be obtained.

[0021] (Compound Represented by Formula (1)) The coating composition according to the present disclosure contains the compound represented by formula (1).

[0022] The structural units that the silsesquioxane derivative used in the present disclosure may contain are referred to as structural units (a) to (d) below.

[0023]

[0024] In the compound represented by formula (1), a and b each independently represent a positive number, and c and d each independently represent 0 or a positive number. In other words, the compound represented by formula (1) contains the structural units (a) and (b) of the structural units (a) to (d) described above, and may also contain at least one of the structural units (c) and (d) as necessary.

[0025] In formula (1), a to d represent the molar ratio of the structural units (a) to (d). In formula (1), a to d represent the relative molar ratio of the structural 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 value of the compound represented by formula (1). Furthermore, when the reaction rate of each raw material for the compound represented by formula (1) is known, or when the yield is 100%, the molar ratio can be determined from the amount of the raw material charged. For example, the molar ratio of each structural unit of the compound represented by formula (1) can be determined by analyzing a sample dissolved in deuterated chloroform or the like. １ H-NMR analysis is carried out, and further analysis is carried out as necessary. ２９ The calculation may also be performed by Si-NMR analysis. The original structure of the compound represented by formula (1) may be estimated from the ratio of the constituent units after decomposing the compound into constituent units with an alkali or the like. If necessary, the molar ratio of each constituent unit of the compound represented by formula (1) may be determined by combining known techniques such as mass spectrometry and IR (infrared absorption spectroscopy) analysis.

[0026] Each of the structural units (b) to (d) in formula (1) may be of only one type, or may be of two or more types. Furthermore, the order of arrangement in formula (1) indicates the composition of the structural units, but does not refer to the order of arrangement of the compound represented by formula (1). Therefore, the condensation form of the structural units in the compound represented by formula (1) does not necessarily have to be the same as the order of arrangement in formula (1). Details of the structural units (a) to (d) and the other structural unit (e) are described below.

[0027] (Structural Unit (a)) The structural unit (a) is a unit in which O is bonded to one silicon atom. ０．５ The Q unit has four silicon atoms (two oxygen atoms). ０．５ It means a unit having four of these.

[0028] The proportion of the structural unit (a) in the compound represented by formula (1) is not particularly limited, but from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, it is preferably 1% by mass to 80% by mass, more preferably 5% by mass to 65% by mass, and particularly preferably 10% by mass to 50% by mass, relative to the total mass of the compound represented by formula (1).

[0029] (Structural Unit (b)) The structural unit (b) is a unit in which O is substituted with 1 silicon atom. ０．５ The T unit has three oxygen atoms (1.5 oxygen atoms) and a monovalent organic group bonded to a silicon atom. ０．５ It means a unit having three of these.

[0030] R in the compound represented by formula (1) １ R may contain one kind alone or two or more kinds. １ From the viewpoints of abrasion resistance, continuous bending resistance, and hardness, R preferably contains a group having a polymerizable functional group, and is more preferably a group having a radically polymerizable functional group or a cationically polymerizable functional group. From the viewpoints of reactivity, abrasion resistance, continuous bending resistance, and hardness, the radically polymerizable group is preferably an ethylenically unsaturated group, and more preferably a (meth)acrylate group, and the cationically polymerizable functional group is preferably an epoxy group or an oxetanyl group. １ When R contains a radical polymerizable group, it preferably contains a group represented by the following formula (R1-1), and more preferably is a group represented by the following formula (R1-1), from the viewpoints of scratch resistance, continuous bending resistance, and hardness. １ When contains a cationically polymerizable group, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, it preferably contains a group represented by the following formula (R1-2), and is more preferably a group represented by the following formula (R1-2):

[0031]

[0032]

[0033] In formula (R1-1) and formula (R1-2), R ｂrepresents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; L １ represents an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, or an aralkylene group having 7 to 12 carbon atoms, and * represents the bonding position to the silicon atom.

[0034] L １ 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. R ｂ Examples of the alkyl group having 1 to 6 carbon atoms in the formula include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group, with a methyl group and an ethyl group being preferred, and a methyl group being more preferred.

[0035] Also, R １ is preferably 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.

[0036] The saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms may be linear or branched. The saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms is preferably 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.

[0037] 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 viewpoints of heat resistance and hardness of the cured product, methyl or ethyl groups are preferred, and methyl groups are more preferred.

[0038] Examples of the unsaturated chain hydrocarbon group having 1 to 10 carbon atoms include a vinyl group, a 2-propenyl group, and an ethynyl group.

[0039] The saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms may be branched. The saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms is preferably a saturated or unsaturated cyclic hydrocarbon group having 4 to 6 carbon atoms.

[0040] The aryl group having 6 to 20 carbon atoms is preferably an aryl group having 6 to 10 carbon atoms.

[0041] Examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a group in which one or more hydrogen atoms of a phenyl group are substituted with an alkyl group having 1 to 10 carbon atoms, and a naphthyl group. From the viewpoints of heat resistance and hardness of the cured product, a phenyl group is preferred.

[0042] The aralkyl group having 7 to 20 carbon atoms is preferably an aralkyl group having 7 to 10 carbon atoms.

[0043] 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, with benzyl groups being preferred from the viewpoints of heat resistance and hardness of the cured product.

[0044] R １ When a part of the group in R is substituted with a substituent or a halogen atom, R １Examples of the alkyl group include a 3-glycidoxypropyl group, a 2-(3,4-epoxycyclohexyl)ethyl group, a 3-(3-ethyloxetan-3-yl)methoxypropyl group, a 3-hydroxypropyl group, a 3-aminopropyl group, a 3-dimethylaminopropyl group, a 3-hydroxypropyl group, a 3-aminopropyl hydrochloride salt, a 3-dimethylaminopropyl hydrochloride salt, a p-styryl group, an N-2-(aminoethyl)-3-aminopropyl group, an N-phenyl-3-aminopropyl group, an N-(vinylbenzyl)-2-aminoethyl-3-aminopropyl hydrochloride salt, a 3-ureidopropyl group, a 3-mercaptopropyl group, a 3-isocyanatopropyl group, a 3-carboxypropyl group, and a 3-chloropropyl group.

[0045] The proportion of the structural unit (b) in the compound represented by formula (1) is not particularly limited, but from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, it is preferably 20% by mass or more, more preferably 30% by mass or more, and particularly preferably 30% by mass to 90% by mass, relative to the total mass of the compound represented by formula (1).

[0046] Furthermore, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, the value of a / b preferably satisfies 0.2<a / b<2.0, more preferably satisfies 0.4<a / b<1.5, and particularly preferably satisfies 0.5<a / b<1.3.

[0047] (Structural Unit (c)) The structural unit (c) is a unit in which O is bonded to one silicon atom. ０．５ (one as an oxygen atom) and two R ５ is a D unit in which O is bonded to a silicon atom. ０．５ It means a unit having two of these.

[0048] In the structural unit (c), R ２ are each preferably independently 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. ２may be the same or different. ２ In the above, preferred embodiments of the saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, the saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, the aryl group having 6 to 20 carbon atoms, and the aralkyl group having 7 to 20 carbon atoms are represented by R １ These are the same as the preferred embodiments of the saturated or unsaturated chain hydrocarbon group having 1 to 20 carbon atoms, the saturated or unsaturated cyclic hydrocarbon group having 3 to 8 carbon atoms, the aryl group having 6 to 20 carbon atoms, and the aralkyl group having 7 to 20 carbon atoms in the above.

[0049] From the viewpoints of abrasion resistance, continuous bending resistance, and hardness, the proportion of the structural unit (c) in the compound represented by formula (1) is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0% by mass, relative to the total mass of the compound represented by formula (1).

[0050] Furthermore, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, it is preferable that the value of c / b satisfies 0≦c / b<0.1, more preferably 0≦c / b<0.05, and particularly preferably 0≦c / b<0.01.

[0051] (Structural Unit (d)) The structural unit (d) is a unit in which O is bonded to one silicon atom. ０．５ (0.5 oxygen atoms), and three R ３ is an M unit in which O is bonded to a silicon atom. ０．５ It means a unit having one

[0052] R ３ are preferably each independently 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. ３ may be the same or different. ３ A preferred embodiment of the present invention is R ２ is the same as:

[0053] From the viewpoints of abrasion resistance, continuous bending resistance, and hardness, the proportion of the structural unit (d) in the compound represented by formula (1) is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0% by mass, relative to the total mass of the compound represented by formula (1).

[0054] Furthermore, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, it is preferable that the value of d / b satisfies 0≦d / b<0.1, more preferably 0≦d / b<0.05, and particularly preferably 0≦d / b<0.01.

[0055] (Other structural units (e)) The silsesquioxane derivative represented by formula (1) may further contain (R ４ O １／２ ) (hereinafter, also referred to as structural unit (e)). ４ 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 the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.

[0056] The structural unit (e) is an alkoxy group, which is a hydrolyzable group contained in the silicon compound described below, or an alkoxy group generated by substitution of the hydrolyzable group of the silicon compound with an alcohol contained in the reaction solvent, and may be one that remains in the molecule without being hydrolyzed or polycondensed, or may be a hydroxyl group that remains in the molecule after hydrolysis without being polycondensed.

[0057] 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. Note that Mw in the present disclosure refers to the molecular weight measured by GPC (gel permeation chromatography) converted using polystyrene as a standard substance. The measurement conditions for Mw can be, for example, the measurement conditions in the Examples described below.

[0058] (Method for Producing Compound Represented by Formula (1)) The compound represented by formula (1) can be produced by a known method. A method for producing a silsesquioxane derivative is disclosed in detail in WO 2013 / 031798 and the like as a method for producing a polysiloxane.

[0059] Among them, the method for producing the compound represented by formula (1) is ｎ Six ｐ (n represents an integer of 0 to 3, p represents an integer of 1 to 4, n+p=4, R represents a group bonded to a silicon atom in the silsesquioxane derivative via a carbon atom, and X represents a hydrolyzable group), using an organic solvent and adding 1.5 molar equivalents or more of water relative to the total amount of hydrolyzable groups possessed by the organosilicon compound (hereinafter also referred to as the "hydrolysis step"). R is preferably a group (H ２ C=CHCOO-R １ -, H ２ C=C(R ３ ) COO-R ２ - and R ４ ~R ８ X is preferably an alkoxy group, a silyloxy group, or a halogen atom, and more preferably an alkoxy group or a silyloxy group.

[0060] In the hydrolysis step, it is preferable to carry out 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. Also, in the hydrolysis step, the hydrolysis and polycondensation reaction of the organosilicon compound and, if necessary, other silicon compounds is carried out to obtain a silsesquioxane derivative as an intermediate product, and then the obtained intermediate product may be further subjected to hydrolysis and polycondensation reaction with the organosilicon compound or the like.

[0061] When obtaining an intermediate product as described above, after carrying out 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) whose terminal portions are blocked with structural unit (e) derived from the organosilicon compound in which n is 3 and p is 1, thereby suppressing an increase in viscosity of the silsesquioxane derivative and improving storage stability.

[0062] The method for producing the compound represented by formula (1) preferably includes a distillation step of subjecting a silicon compound to hydrolysis and polycondensation reaction in the presence of a reaction solvent, and then distilling off the reaction solvent, by-products, residual monomers, water, and the like from the reaction solution.

[0063] Among the organosilicon compounds, those having an acryloyl group include, for example, (3-acryloyloxypropyl)trimethoxysilane, (3-acryloyloxypropyl)triethoxysilane, (8-acryloyloxyoctyl)trimethoxysilane, and (3-acryloyloxypropyl)trichlorosilane.

[0064] Among the organosilicon compounds, those having a methacryloyl group include, for example, (3-methacryloyloxypropyl)trimethoxysilane, (3-methacryloyloxypropyl)triethoxysilane, (8-methacryloyloxyoctyl)trimethoxysilane, and (3-methacryloyloxypropyl)trichlorosilane.

[0065] Among the above-mentioned organosilicon compounds, those having an oxetanyl group include, for example, (3-ethyl-3-oxetanylmethoxypropyl)trimethoxysilane, (3-ethyl-3-oxetanylmethoxypropyl)triethoxysilane, (3-methyl-3-oxetanylmethoxypropyl)trimethoxysilane, and (3-oxetanylmethoxypropyl)trichlorosilane.

[0066] Among the organosilicon compounds, those having an epoxy group include, for example, (glycidyloxypropyl)trimethoxysilane, (glycidyloxypropyl)triethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0067] Examples of silicon compounds that give the structural unit (a) upon hydrolysis include tetramethoxysilane, tetraethoxysilane, and tetrapropoxysilane.

[0068] Examples of the organosilicon compound in which n is 3 and p is 1 include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, octyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, benzyltrimethoxysilane, cyclohexyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, p-styryltrimethoxysilane, ethynyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, ... trimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-isocyanatepropyltriethoxysilane, tris(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropyltrimethoxysilane, 3-ethyl-3-[{3-(trimethoxysilyl)propoxy}methyl]oxetane, and 3-ethyl-3-[{3-(triethoxysilyl)propoxy}methyl]oxetane.

[0069] Examples of the organosilicon compound in which n is 2 and p is 2 include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldidiethoxysilane, propylmethyldimethoxysilane, octylmethyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, benzylmethyldimethoxysilane, cyclohexylmethyldimethoxysilane, vinylmethyldimethoxysilane, allylmethyldimethoxysilane, p-styrylmethyldimethoxysilane, ethynylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, silane, 3-glycidoxypropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropylmethyldimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropylmethyldimethoxysilane hydrochloride, 3-ureidopropylmethyldialkoxysilane, 3-isocyanatopropylmethyldiethoxysilane, (3-acryloxypropyl)methyldimethoxysilane, and (3-methacryloxypropyl)methyldiethoxysilane.

[0070] Examples of the organosilicon compound in which n is 1 and p is 3 include hexamethyldisiloxane, trimethylmethoxysilane, trimethylethoxysilane, trimethylchlorosilane, and dimethylphenylmethoxysilane.

[0071] In the hydrolysis step, the reaction solvent is not particularly limited, but it is preferable to use an alcohol as the organic solvent. The alcohol is an alcohol in the narrow sense represented by the general formula R—OH, and is a compound having no functional groups other than an alcoholic hydroxyl group. The alcohol is not particularly limited, and examples thereof 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, these alcohols may be used alone or in combination.

[0072] The organic solvent used in the hydrolysis step may be alcohol alone, or may be a mixed solvent with at least one auxiliary solvent. The auxiliary solvent may be either a polar solvent or a non-polar 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.

[0073] 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 in the organosilicon compound to carry out hydrolysis and further condensation. Furthermore, in the hydrolysis step, 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 in the organosilicon compound, from the viewpoints of the cure shrinkage, hardness, storage stability, and curl suppression during curing of the resulting compound represented by formula (1).

[0074] The hydrolysis and polycondensation reaction of the silicon compound may be carried out without a catalyst or with a catalyst. When a catalyst is used, preferred catalysts include inorganic acids such as sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid; organic acids such as formic acid, acetic acid, oxalic acid, and paratoluenesulfonic acid; and base catalysts such as ammonia, tetramethylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate. The amount of catalyst used is preferably an amount corresponding to 0.01 mol% to 20 mol%, and more preferably an amount corresponding to 0.1 mol% to 10 mol%, based on the total amount (mol) of silicon atoms contained in the silicon compound.

[0075] The completion of the hydrolysis and polycondensation reaction in the hydrolysis step can be appropriately detected by methods described in various publications, etc. In the hydrolysis step of the method for producing the compound represented by formula (1), an auxiliary agent can be added to the reaction system.

[0076] By providing the above-described 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. The distillation step can be carried out under normal pressure or reduced pressure, at room temperature or under heating, or under cooling.

[0077] The method for producing the compound represented by formula (1) may include a neutralization step of neutralizing the catalyst before the distillation step, and may also include a step of removing the salt produced by the neutralization by washing with water or the like.

[0078] Furthermore, the compound represented by formula (1) may contain a side-chain functional group derived from the silicon compound used as a raw material in the production, which is a group formed by ring-opening by the addition of an acid or the like to an oxetanyl group or an epoxy group, or may contain a hydroxyalkyl group formed by decomposition of an organic group having a (meth)acryloyl group, or a group formed by the addition of an acid or the like to an unsaturated hydrocarbon group. Specific examples include those in which a structure represented by formula (A) and / or a structure represented by formula (B) below is included as part of formula (1). The content ratio of the original oxetanyl group- or epoxy group-containing organic group, the original (meth)acryloyl group-containing organic group, or the original unsaturated hydrocarbon group-containing organic group derived from the silicon compound as a raw material is 50 mol% or less, which is sufficient for implementing the present disclosure, and is preferably 30 mol% or less, and more preferably 10 mol% or less. In both formulas (A) and (B), T units are exemplified, but similar D units, M units, etc. may also be used.

[0079]

[0080]

[0081] (Polymerization initiator) The coating composition according to the present disclosure preferably further contains a polymerization initiator, and more preferably contains a radical polymerization initiator. The polymerization initiator is not particularly limited, and examples thereof include a photopolymerization initiator and a thermal polymerization initiator. Examples of the photopolymerization initiator include a photoradical polymerization initiator. Examples of the thermal polymerization initiator include a thermal radical polymerization initiator. Known compounds may be used as the photopolymerization initiator and the thermal polymerization initiator.

[0082] Examples of photopolymerization initiators include 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate, 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, and 2-benzyl-2-diphenylpropan-1-one. Acetophenone compounds such as methylamino-1-(4-morpholinophenyl)-butan-1-one, diethoxyacetophenone, oligo[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone] and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)benzyl]phenyl}-2-methyl-propan-1-one; benzophenone compounds such as benzophenone, 4-phenylbenzophenone, 2,4,6-trimethylbenzophenone and 4-benzoyl-4'-methyldiphenyl sulfide compounds such as methyl benzoyl formate, oxyphenylacetic acid 2-[2-oxo-2-phenylacetoxyethoxy]ethyl ester, and oxyphenylacetic acid 2-[2-hydroxyethoxy]ethyl ester; phosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; benzoin, benzoyl benzoin-based compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; titanocene-based compounds; acetophenone / benzophenone hybrid-based photoinitiators such as 1-(4-(4-benzoylphenylsulfanyl)phenyl)-2-methyl-2-(4-methylphenylsulfinyl)propan-1-one; oxime ester-based photopolymerization initiators such as 1-(4-phenylthiophenyl)-2-(O-benzoyloxime)-1,2-octanedione; and camphorquinone.These may be used alone or in combination of two or more.

[0083] There are no particular limitations on the thermal radical polymerization initiator, and examples thereof include peroxides and azo-based initiators.

[0084] Examples of peroxides include hydrogen peroxide; inorganic peroxides such as sodium persulfate, ammonium persulfate, and potassium persulfate; 1,1-bis(t-butylperoxy)2-methylcyclohexane, 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, and 2,2-bis(4,4-dimethylcyclohexane). -butylperoxycyclohexyl)propane, 1,1-bis(t-butylperoxy)cyclododecane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di(m-toluoylperoxy)hexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy 2-ethylhexyl monocarbonate, t- Hexyl peroxybenzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butyl peroxyacetate, 2,2-bis(t-butylperoxy)butane, t-butyl peroxybenzoate, n-butyl-4,4-bis(t-butylperoxy)valerate, di-t-butylperoxyisophthalate, α,α'-bis(t-butylperoxy)diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane Examples of organic peroxides include dimethylsilyl peroxide, t-butyl cumyl peroxide, di-t-butyl peroxide, p-menthane hydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, diisopropylbenzene hydroperoxide, t-butyltrimethylsilyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-hexyl hydroperoxide, and t-butyl hydroperoxide. These may be used alone or in combination of two or more.

[0085] Examples of azo initiators include azo compounds such as 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2-(carbamoylazo)isobutyronitrile, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, azodi-t-octane, and azodi-t-butane. These may be used alone or in combination of two or more. A redox reaction can also be carried out by combining a peroxide with a redox polymerization initiation system that uses a reducing agent such as ascorbic acid, sodium ascorbate, sodium erythorbate, tartaric acid, citric acid, a metal salt of formaldehyde sulfoxylate, sodium thiosulfate, sodium sulfite, sodium bisulfite, sodium metabisulfite, or ferric chloride.

[0086] The content of the polymerization initiator in the coating composition according to the present disclosure is preferably 0.01 parts by mass to 20 parts by mass, more preferably 0.1 parts by mass to 10 parts by mass, and even more preferably 1 part by mass to 5 parts by mass, relative to 100 parts by mass of the compound represented by formula (1).

[0087] (Inorganic Particles) The coating composition according to the present disclosure preferably contains inorganic particles, more preferably inorganic particles having an average particle size of less than 1 μm. Examples of materials for the inorganic particles 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.

[0088] The average particle size of the inorganic particles (unless otherwise specified, volume-based median diameter) is preferably 0.05 μm or more and less than 1 μm, and more preferably 0.1 μm to 0.5 μm. The average particle size of the inorganic particles in the present disclosure refers to 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 using a particle size distribution measuring device based on a laser light diffraction scattering method.

[0089] The inorganic particles may be surface-treated. Among them, inorganic particles having a polymerizable group on the surface are preferred, inorganic particles having an ethylenically unsaturated group on the surface are more preferred, and inorganic particles having a (meth)acrylate group on the surface are particularly preferred. The surface treatment method for the inorganic particles is not particularly limited, and known methods can be used.

[0090] The mass ratio of the inorganic particles in the coating composition excluding the solvent and the polymerization initiator in the coating composition according to the present disclosure is preferably 50 mass % or less, more preferably 5 mass % to 50 mass %, and even more preferably 10 mass parts to 40 mass parts, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness.

[0091] (Other Polymerizable Compounds) From the viewpoints of scratch resistance, continuous flex resistance, and hardness, the coating composition according to the present disclosure preferably contains a polymerizable compound other than the compound represented by formula (1) (hereinafter also referred to as "other polymerizable compounds"). The other polymerizable compound is not particularly limited as long as it is a compound capable of undergoing a polymerization reaction in the presence of the compound represented by formula (1) and a polymerization initiator. Examples of the other polymerizable compound include silsesquioxane derivatives other than the compound represented by formula (1), (meth)acrylate compounds, compounds having an ethylenically unsaturated group, epoxy compounds (compounds having an epoxy group), compounds having an oxetanyl group (oxetanyl group-containing compounds), and compounds having a vinyl ether group (vinyl ether compounds).

[0092] Among these, the other polymerizable compounds preferably include a bifunctional polymerizable compound from the viewpoints of abrasion resistance, continuous flex resistance, and hardness, and more preferably include at least one compound selected from the group consisting of a bifunctional (meth)acrylate compound and a bifunctional epoxy compound. Furthermore, as the bifunctional (meth)acrylate compound, from the viewpoints of abrasion resistance, continuous flex resistance, and hardness, an alkylene glycol di(meth)acrylate compound is preferred, and a linear alkylene glycol di(meth)acrylate compound is more preferred. Furthermore, from the viewpoints of abrasion resistance, continuous flex resistance, and hardness, the number of carbon atoms of the alkylene glycol is preferably 4 to 8, and more preferably 5 to 7.

[0093] The (meth)acrylate compound is not particularly limited, and examples thereof include a compound having one (meth)acryloyl group (hereinafter also referred to as a "monofunctional (meth)acrylate") and a compound having two or more (meth)acryloyl groups (hereinafter also referred to as a "polyfunctional (meth)acrylate").

[0094] Examples of the monofunctional (meth)acrylate include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate; monofunctional (meth)acrylates having an alicyclic group such as cyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and tricyclodecanemethylol (meth)acrylate; monofunctional (meth)acrylates having an aromatic group such as benzyl (meth)acrylate and phenyl (meth)acrylate; (Meth)acrylates of alkylene oxide adducts of phenol derivatives such as (meth)acrylate of phenol ethylene oxide adduct, (meth)acrylate of phenol propylene oxide adduct, (meth)acrylate of modified nonylphenol ethylene oxide adduct, (meth)acrylate of nonylphenol propylene oxide adduct, (meth)acrylate of alkylene oxide adduct of para-cumylphenol, orthophenylphenol (meth)acrylate, and (meth)acrylate of alkylene oxide adduct of orthophenylphenol; monofunctional (meth)acrylates having an alkoxyalkyl group such as 2-ethylhexyl carbitol (meth)acrylate; monofunctional (meth)acrylates having a heterocycle such as tetrahydrofurfuryl (meth)acrylate and N-(2-(meth)acryloxyethyl)hexahydrophthalimide; Hydroxylalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and hydroxyhexyl (meth)acrylate; monofunctional (meth)acrylates having a hydroxyl group and an aromatic group such as 2-hydroxy-3-phenoxypropyl (meth)acrylate; alkylene glycol mono(meth)acrylates such as diethylene glycol mono(meth)acrylate, dipropylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, and tripropylene glycol mono(meth)acrylate;and monofunctional (meth)acrylates having a carboxy group such as ω-carboxypolycaprolactone mono(meth)acrylate and monohydroxyethyl phthalate (meth)acrylate.

[0095] Examples of polyfunctional (meth)acrylates include polyethylene glycol di(meth)acrylates such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate; polypropylene glycol di(meth)acrylates such as dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and tetrapropylene glycol di(meth)acrylate; Examples of the di(meth)acrylate include 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide-modified neopentyl glycol di(meth)acrylate, ethylene oxide-modified bisphenol A di(meth)acrylate, propylene oxide-modified bisphenol A di(meth)acrylate, ethylene oxide-modified hydrogenated bisphenol A di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane allyl ether di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexaacrylate.

[0096] As the polyfunctional (meth)acrylate, a urethane (meth)acrylate can also be used. Examples of the urethane (meth)acrylate include a compound obtained by addition reaction of an organic polyisocyanate with a hydroxyl group-containing (meth)acrylate, and a compound obtained by addition reaction of an organic polyisocyanate with a polyol and a hydroxyl group-containing (meth)acrylate. The monofunctional (meth)acrylate, polyfunctional (meth)acrylate, etc. may be used alone or in combination of two or more types, or different types may be used in combination.

[0097] Here, examples of polyols include low-molecular-weight polyols, polyether polyols, polyester polyols, and polycarbonate polyols. Examples of low-molecular-weight polyols include ethylene glycol, propylene glycol, neopentyl glycol, cyclohexane dimethylol, and 3-methyl-1,5-pentanediol. Examples of polyether polyols include polypropylene glycol and polytetramethylene glycol. Examples of polyester polyols include reaction products of these low-molecular-weight polyols and / or polyether polyols with dibasic acids such as adipic acid, succinic acid, phthalic acid, hexahydrophthalic acid, and terephthalic acid, or acid components such as anhydrides thereof. These may be used alone or in combination of two or more types, or different types may be used in combination.

[0098] Examples of organic polyisocyanates include tolylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Examples of hydroxyl group-containing (meth)acrylates include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and hydroxyl group-containing polyfunctional (meth)acrylates such as pentaerythritol tri(meth)acrylate, di(meth)acrylate of an adduct of 3 moles of alkylene oxide with isocyanuric acid, and dipentaerythritol penta(meth)acrylate. These may be used alone or in combination of two or more, or different types may be used in combination.

[0099] A compound having one ethylenically unsaturated group per molecule other than the (meth)acrylate compound may be added to the curable composition. The ethylenically unsaturated group is preferably a (meth)acryloyl group, a maleimide group, a (meth)acrylamide group, or a vinyl group. Specific examples of the compound having an ethylenically unsaturated group include (meth)acrylic acid, a Michael addition dimer of acrylic acid, N-(2-hydroxyethyl)citraconimide, N,N-dimethylacrylamide, acryloylmorpholine, N-vinylpyrrolidone, and N-vinylcaprolactam. These compounds may be used alone or in combination of two or more.

[0100] 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. For example, compounds described in JP 2011-42755 A may be used as these compounds. There are no particular limitations on the silicone, and known silicones can be used, such as polydimethylsilicone, polydiphenylsilicone, and polymethylphenylsilicone, with those having functional groups at their terminals and / or side chains being preferred. There are no particular limitations on the functional group, and examples include (meth)acryloyl groups, epoxy groups, oxetanyl groups, vinyl groups, hydroxyl groups, carboxy groups, amino groups, and thiol groups.

[0101] The mass ratio of the other polymerizable compounds in the coating composition excluding the solvent and polymerization initiator in the coating composition according to the present disclosure is preferably 0% by mass or more and 50% by mass or less, more preferably more than 0% by mass and less than 35% by mass, and even more preferably 10% by mass to 30% by mass, from the viewpoints of abrasion resistance, continuous flex resistance, and hardness. Furthermore, the mass ratio of the bifunctional (meth)acrylate compound in the coating composition excluding the solvent and polymerization initiator in the coating composition according to the present disclosure is preferably 0% by mass or more and 50% by mass or less, more preferably more than 0% by mass and less than 35% by mass, and even more preferably 10% by mass to 30% by mass, from the viewpoints of abrasion resistance, continuous flex resistance, and hardness. The mass proportion of the bifunctional (meth)acrylate compound relative to the total mass of the other polymerizable compounds in the coating composition according to the present disclosure is, from the viewpoints of abrasion resistance, continuous bending resistance, and hardness, preferably 50 mass % or more, more preferably 80 mass % or more, even more preferably 90 mass % or more, and particularly preferably 100 mass %.

[0102] (Other Components) The coating composition according to the present disclosure may further contain other components in addition to the compound represented by Formula (1), the polymerization initiator, the inorganic particles, and other polymerizable compounds. The other components are not particularly limited, and examples thereof include solvents, resins, silicones, monomers, fillers, surfactants, antistatic agents (e.g., conductive polymers), leveling agents, photosensitizers, UV absorbers, antioxidants, heat resistance improvers, stabilizers, lubricants, pigments, dyes, plasticizers, suspending agents, adhesion promoters, nanoparticles, nanofibers, and nanosheets. The curable composition according to the present disclosure may also contain silane-based reactive diluents such as tetraalkoxysilanes, trialkoxysilanes, dialkoxysilanes, monoalkoxysilanes, and disiloxanes.

[0103] The coating composition according to the present disclosure may or may not contain a solvent, for example, 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.

[0104] (Average Indentation Hardness of Cured Film) From the viewpoints of abrasion resistance, continuous bending resistance, and hardness, the coating composition according to the present disclosure is preferably capable of forming a film having an average indentation hardness of 0.45 GPa or more at a surface depth of 200 nm to 400 nm as measured with a nanoindenter, more preferably 0.50 GPa or more, even more preferably 0.48 GPa to 1.5 GPa, and particularly preferably 0.48 GPa to 1.0 GPa.

[0105] The method for measuring the average indentation hardness of a cured film in the present disclosure is as follows. A photocured film is prepared in the same manner as in the measurement of the indentation modulus. Using the resulting photocured film, indentation hardness is measured at 23°C and a strain rate of 0.05 / s using a nanoindenter (Nano Indenter G200, manufactured by Agilent Technologies, Inc., using a Berkovich indenter). The hardness is calculated by averaging the hardness values ​​at indentation depths of 200 nm to 400 nm.

[0106] (Resistant to breakage of cured film due to continuous bending) It is preferable that a film having a thickness of less than 10 μm obtained by curing the coating composition according to the present disclosure does not break even when continuously bent inward at a bending radius R of 1.5 mm 200,000 times, more preferably does not break even when continuously bent inward at a bending radius R of 1.0 mm 100,000 times, and particularly preferably does not break even when continuously bent inward at a bending radius R of 1.0 mm 200,000 times.

[0107] The method for measuring fracture resistance due to continuous bending in the present disclosure is as follows: A photocured film is prepared in the same manner as in the measurement of indentation modulus. The resulting photocured film is placed in a durability testing machine DMLHP-CS manufactured by Yuasa System Equipment Co., Ltd. with the coated film surface facing inward, and a repeated bending test is performed 100,000 or 200,000 times at a bending radius of 1 mm or 1.5 mm at a rate of 1 time per 2 seconds, and the presence or absence of fractures or cracks is confirmed visually.

[0108] (Method of producing coating composition) The method of producing the coating composition according to the present disclosure is not particularly limited, and a known method can be used. ｎ Six ｐ (n represents an integer of 0 to 3, p represents an integer of 1 to 4, n+p=4, R represents a group bonded to a silicon atom in the silsesquioxane derivative via a carbon atom, and X represents a hydrolyzable group), using an organic solvent and adding 1.5 molar equivalents or more of water relative to the total amount of hydrolyzable groups possessed by the organosilicon compound. The hydrolysis step in the method for producing a coating composition according to the present disclosure is the same as the hydrolysis step in the method for producing a compound represented by formula (1), and preferred aspects are also the same.

[0109] [Coating Film] The coating film according to the present disclosure is obtained by curing the coating composition according to the present disclosure. For example, the coating film according to the present disclosure can be obtained by irradiating the coating composition according to the present disclosure with active energy rays or by heating the coating composition according to the present disclosure.

[0110] The coating composition according to the present disclosure may be cured after being applied to a substrate. The coating composition according to the present disclosure may or may not contain a solvent. When the coating composition contains a solvent, it is preferable to remove the solvent before curing.

[0111] When applying the coating composition according to the present disclosure to a substrate, the method for applying the coating composition is not particularly limited. Examples of application methods include common coating methods such as inkjet coating, casting, spin coating, bar coating, dip coating, spray coating, roll coating, flow coating, and gravure coating. The thickness of the coating composition according to the present disclosure is not particularly limited and may be appropriately determined depending on the purpose. The substrate to which the coating composition according to the present disclosure is applied is not particularly limited, and examples thereof include wood, metal, inorganic materials, plastics, paper, fibers, and fabrics. Metals include copper, silver, iron, aluminum, silicon, silicon steel, and stainless steel. 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, polyvinyl chloride resins, polycarbonate resins, epoxy resins, polyamide resins such as nylon and aramid, fluororesins such as polyimide resins, polyamideimide resins, and tetrafluoroethylene resins, polyolefin resins such as cross-linked polyethylene resins, vinylidene chloride resins, acrylonitrile-butadiene-styrene (ABS) resins, polystyrene resins, polyacrylonitrile resins, cycloolefin polymers (COP), cycloolefin copolymers (COC), acetate resins, polyarylates, cellophane, norbornene resins, acetylcellulose resins such as triacetylcellulose (TAC), composite resins such as polychloroprene, polyphenylene sulfide, polysulfone, polyethersulfone, polyetheretherketone, polyurethane resins, and glass epoxy resins, and various fiber-reinforced resins. Examples of fibers include natural fibers, recycled fibers, semi-synthetic fibers, metal fibers, glass fibers, carbon fibers, ceramic fibers, and known chemical fibers.The fabric may be a woven fabric or a nonwoven fabric, and may be made using, for example, the fibers described above. These materials may be used alone, or two or more may be combined, mixed, or composited. The shape of the substrate is not particularly limited, and examples thereof include plate-like, sheet-like, film-like, rod-like, spherical, fibrous, powder-like, lenticular, and other regular or irregular shapes.

[0112] (Curing Method) In the present disclosure, the curing method and curing conditions are selected depending on whether the coating composition is active energy ray-curable and / or thermosetting. Furthermore, the curing conditions (e.g., the type of light source and the amount of light irradiation in the case of active energy ray-curable compositions, and the heating temperature and heating time in the case of thermosetting compositions) are appropriately selected depending on the type and amount of polymerization initiator contained in the coating composition and the types of other polymerizable compounds, etc.

[0113] (1) Active Energy Ray Curing Method When the coating composition according to the present disclosure is an active energy ray-curable composition, the curing method may involve irradiating the composition with active energy rays using a known active energy ray irradiation device or the like. Examples of active energy rays include electron beams, and light such as ultraviolet light, visible light, and X-rays. Light is preferred, and ultraviolet light is more preferred from the viewpoint of being able to use inexpensive equipment. Examples of ultraviolet light 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 of the coating film coated with the coating composition according to the present disclosure may be selected depending on the purpose, application, etc., and the light irradiation intensity in the light wavelength region (which varies depending on the type of photopolymerization initiator, but preferably light with a wavelength of 220 nm to 460 nm is used) effective for activating the active energy ray polymerization initiator (which is referred to as a photopolymerization initiator in the case of photocurable initiators) is 0.1 mW / cm ２ ~1000mW / cm ２The irradiation energy should be appropriately set depending on the type of active energy ray, the formulation, etc. The light irradiation time of the coating may also be selected depending on the purpose, application, etc., and it is preferable that the integrated light amount, which is expressed as the product of the light irradiation intensity and the light irradiation time in the light wavelength range, is 10 mJ / cm. ２ ~7,000mJ / cm ２ It is preferable that the light irradiation time is set so that the integrated light amount is 200 mJ / cm ２ ~5,000mJ / cm ２ More preferably, 500 mJ / cm ２ ~4,000mJ / cm ２ When the integrated light amount is within the above range, the curing of the composition proceeds smoothly, and a uniform cured product can be easily obtained.

[0114] Furthermore, heat curing can be appropriately combined before and / or after photocuring. For example, a substrate having a shaded area when irradiated with light may be impregnated with the composition, and then the composition may be irradiated with light to first cure the composition in the area exposed to light, and then heat may be applied to cure the composition in the area not exposed to light, thereby performing two-stage curing. There are no particular limitations on such substrates, and examples include substrates with complex shapes such as fabric-like, fibrous, powder-like, porous, and uneven, and may also have a shape in which two or more of these shapes are combined.

[0115] The coating film according to the present disclosure is preferably further heated before or after UV curing. By performing additional heating, the hardness is superior, and the abrasion resistance and continuous flex resistance are also superior. The heating temperature of the coating film after curing is preferably 60°C to 200°C, more preferably 80°C to 180°C, and even more preferably 100°C to 150°C. The curing temperature may be constant or may be increased. A combination of temperature increase and temperature decrease may also be used. The heating time of the coating film after curing is preferably 1 minute to 360 minutes, more preferably 5 minutes to 120 minutes, and even more preferably 5 minutes to 60 minutes.

[0116] (2) Thermal Curing Method When the coating composition according to the present disclosure is a thermosetting composition, the curing method and 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 constant or may be increased. A combination of temperature increase and decrease 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-mentioned preferred conditions, a uniform cured film free of blistering, cracks, etc. can be formed.

[0117] (Applications of Coating Films, etc.) The coating composition according to the present disclosure has excellent hardness and can therefore be suitably applied to hard coating films. Furthermore, by curing the coating composition according to the present disclosure, a hard coating film with excellent flex resistance can be obtained. The coating composition according to the present disclosure may be provided on a substrate; for example, a substrate having a hard coating film can be obtained by curing the coating composition applied to the substrate. The coating composition according to the present disclosure may contain various components as needed. The hard coating film according to the present disclosure and the substrate having the coating film according to the present disclosure have excellent flex resistance and can therefore be suitably used in flexible devices such as bendable foldable devices and rollable rollable devices, displays such as electronic paper and bendable flexible displays, optical components such as lenses, and the like.

[0118] Next, the present disclosure will be specifically described based on examples and comparative examples, but the present disclosure is not limited to the following examples.

[0119] Synthesis Example 1: 38.1 g (0.25 mol) of tetramethoxysilane and 43.4 g of 1-propanol were weighed into a 200 mL four-neck flask equipped with a dropping funnel and a stirrer. While stirring at room temperature (25°C, the same applies below), 12.8 g (0.035 mol) of a 25% by weight tetramethylammonium hydroxide methanol solution was added dropwise from the dropping funnel to obtain a tetraalkoxysilane solution. Separately, 62.8 g (0.25 mol) of 3-methacryloyloxypropyltrimethoxysilane, 74.5 g of 1-propanol, and 31.5 g of pure water were weighed into a 500 mL four-neck flask equipped with a dropping funnel and a stirrer. The mixture was thoroughly stirred, and the tetraalkoxysilane solution was added dropwise while heating to 60°C. The mixture was then further stirred at 60°C for 2 hours. 2.5 g (0.04 mol) of nitric acid was added to neutralize the mixture, and the 1-propanol was distilled off under reduced pressure. 50 g of propylene glycol monobutyl ether was added thereto, and the mixture was transferred to a separatory funnel. The aqueous phase was removed to obtain 101 g of a 50% by mass propylene glycol monobutyl ether solution of the silsesquioxane derivative S1.

[0120] Synthesis Example 2 The same procedure as in Synthesis Example 1 was repeated, except that the amount of tetramethoxysilane was changed to 45.7 g (0.3 mol) and the amount of 3-methacryloyloxypropyltrimethoxysilane was changed to 49.7 g (0.2 mol), to obtain 102 g of a 50% by mass propylene glycol monobutyl ether solution of silsesquioxane derivative S2.

[0121] Synthesis Example 3 The same procedure as in Synthesis Example 1 was repeated, except that the amount of tetramethoxysilane was changed to 42.6 g (0.28 mol) and the amount of 3-methacryloyloxypropyltrimethoxysilane was changed to 54.6 g (0.22 mol), to obtain 106 g of a 50% by mass propylene glycol monobutyl ether solution of silsesquioxane derivative S3.

[0122] Synthesis Example 4 The same procedure as in Synthesis Example 1 was repeated, except that the amount of tetramethoxysilane was changed to 24.4 g (0.16 mol) and the amount of 3-methacryloyloxypropyltrimethoxysilane was changed to 59.6 g (0.24 mol), to obtain 98 g of a 50% by mass propylene glycol monobutyl ether solution of silsesquioxane derivative S4.

[0123] Synthesis Example 5: 24.8 g (1 mol) of 3-methacryloyloxypropyltrimethoxysilane and 407 g of 2-propanol were weighed into a 500 mL four-neck flask equipped with a stirrer and a dropping funnel and stirred at room temperature. While heating this mixture to 50°C, a mixed aqueous solution of 1.3 g (0.012 mol) of 35% by mass aqueous hydrochloric acid and 53 g of pure water was added dropwise, followed by cooling to room temperature and stirring for 12 hours. The solvent and water were removed from the resulting solution under reduced pressure to obtain 181 g of silsesquioxane derivative S5.

[0124] Synthesis Example 6 The same procedure as in Synthesis Example 1 was repeated, except that the amount of tetramethoxysilane was changed to 18.3 g (0.12 mol) and the amount of 3-methacryloyloxypropyltrimethoxysilane was changed to 69.5 g (0.28 mol), to obtain 102 g of a 50% by mass propylene glycol monobutyl ether solution of silsesquioxane derivative S6.

[0125] Synthesis Example 7 50.2 g (0.33 mol) of tetramethoxysilane, 69.6 g (0.25 mol) of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane, and 89.8 g of 1-propanol were weighed into a 500 mL four-neck flask equipped with a dropping funnel and a stirrer and stirred at 40° C. To this mixture, 14.8 g (0.04 mol) of a 25% by mass solution of tetramethylammonium hydroxide in methanol was added dropwise, followed by the dropwise addition of a mixture of 37.3 g of pure water and 37.3 g of 1-propanol, followed by stirring at 70° C. for 6 hours. To this mixture, 2.5 g (0.04 mol) of nitric acid was added to neutralize, and the 1-propanol was distilled off under reduced pressure. 50 g of propylene glycol monobutyl ether was added thereto, and the mixture was transferred to a separatory funnel. The aqueous phase was removed to obtain 135 g of a 50% by mass propylene glycol monobutyl ether solution of silsesquioxane derivative S6.

[0126] Synthesis Example 8 278.4 g (1 mol) of 3-[(3-ethyloxetan-3-yl)methoxy]propyl(trimethoxy)silane and 246 g of 2-propanol were weighed into a 1000 mL four-neck flask equipped with a stirrer and a dropping funnel and stirred at 80°C for 1 hour. A separately prepared mixed aqueous solution of 9.1 g (0.025 mol) of 25% by mass aqueous tetramethylammonium hydroxide and 47.3 g of pure water was added dropwise from the dropping funnel over approximately 1 hour to this mixed solution while stirring the reaction solution, and then the mixture was stirred at 80°C for 1 hour. The reaction solution was neutralized with a mixed aqueous solution of concentrated sulfuric acid (1.3 g, 0.013 mol) and pure water (25.7 g), and the solvent and the like were then distilled off under reduced pressure. Further, diisopropyl ether was added, and the mixture was transferred to a separatory funnel and washed with pure water, and then dehydrated. The solvent and the like were distilled off under reduced pressure, thereby obtaining 209.3 g of silsesquioxane derivative S7.

[0127] Example 1 Preparation of Photocurable Coating Composition 0.05 parts by mass of 1-hydroxycyclohexyl phenyl ketone was added to 1 part by mass of the silsesquioxane derivative S1 solution obtained in Synthesis Example 1, and the mixture was stirred using a planetary centrifugal mixer to prepare photocurable coating composition 1.

[0128] (Examples 2 to 23) Each component was added so as to obtain the composition shown in Table 1, and 0.05 parts by mass of 1-hydroxycyclohexyl phenyl ketone was added to 1 part by mass of the solution of the compound represented by formula (1), and the mixture was stirred using a planetary centrifugal mixer to prepare each photocurable coating composition.

[0129] (Example 24) Each component was added so as to obtain the composition shown in Table 1, and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate was added to 1 part by mass of the solution of the compound represented by formula (1), and the mixture was stirred with a planetary centrifugal mixer to prepare each photocurable coating composition.

[0130] Comparative Example 1 A photocurable coating composition was prepared by adding 0.05 parts by mass of 1-hydroxycyclohexyl phenyl ketone and 1 part by mass of propylene glycol monobutyl ether to 1 part by mass of the silsesquioxane derivative S5 obtained in Synthesis Example 5, and stirring the mixture with a planetary centrifugal mixer.

[0131] Comparative Example 2 A photocurable coating composition was prepared by adding 0.05 parts by mass of 1-hydroxycyclohexyl phenyl ketone to 1 part by mass of silica in a silica / propylene glycol monobutyl ether dispersion (silica mass 40% by mass), and stirring the mixture with a planetary centrifugal mixer.

[0132] (Comparative Examples 3 to 5) Each component was added so as to obtain the composition shown in Table 1, and 0.05 parts by mass of 2-hydroxy-2-methyl-1-phenylpropan-1-one was added per 1 part by mass of the (meth)acrylate compound used, and the mixture was stirred with a planetary centrifugal mixer to prepare each photocurable coating composition.

[0133] (Comparative Example 6) Each component was added so as to obtain the composition shown in Table 1, and 0.02 parts by mass of 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate was added per 1 part by mass of the (meth)acrylate compound used, and the mixture was stirred with a planetary centrifugal mixer to prepare each photocurable coating composition.

[0134] <Preparation of Photocured Films> Each of the coating compositions prepared as described above was applied to a 50 μm thick polyethylene terephthalate (PET) film (Cosmoshine A4300, manufactured by Toyobo Co., Ltd.). Specifically, each coating composition was applied using a No. 5 or 8 bar coater, and then the applied coating composition was dried at 60°C for 10 minutes, and then irradiated with ultraviolet light under the following conditions to cure, thereby preparing a photocured film (coated film). The film thickness was approximately 3 μm or 5 μm. -Ultraviolet Light Irradiation Conditions- Lamp: High-pressure mercury lamp (ECS-4011GX, manufactured by iGraphics Co., Ltd.) Lamp height: 10 cm Conveyor speed: 5.75 m / min Integrated light intensity per pass: 360 mJ / cm ２ (UV-A, measured value using UV POWER PUCK II manufactured by EIT) Atmosphere: Nitrogen Number of passes: 10

[0135] <Measurement of Indentation Hardness> The indentation hardness of the photocured film prepared as described above was measured as follows. Specifically, indentation hardness was measured at 23°C and a strain rate of 0.05 / s using a nanoindenter (Nano Indenter G200 manufactured by Agilent Technologies, Inc., using a Berkovich indenter). The hardness was calculated by averaging the hardness values ​​at indentation depths of 200 nm to 400 nm. The results are shown in Table 1.

[0136] <Evaluation of continuous bending resistance> The photocured film prepared as described above was set in a durability testing machine DMLHP-CS manufactured by Yuasa System Co., Ltd. with the coated film surface facing inward, and a repeated bending test was performed 200,000 times at a bending radius of 1 mm or 1.5 mm and a speed of 1 bending / 2 seconds. A rating of A was given if no cracks were observed in the coating film layer even after 200,000 bendings, a rating of B was given if cracks were observed after 50,000 to 200,000 bendings, and a rating of C was given if cracks were observed after less than 50,000 bendings. The results are shown in Table 1. The test was performed in a constant temperature and humidity environment set at a temperature of 23°C and a humidity of 50%.

[0137] <Evaluation of Scratch Resistance> The photocured film prepared as described above was placed in a flat abrasion tester PAS-400 manufactured by Daiei Scientific Instruments Co., Ltd. with the coated film surface facing upward, and the surface was subjected to a pressure of 1.5 kg / cm. ２Steel wool #0000 (manufactured by Nippon Steel Wool Co., Ltd.) was brought into contact with the coating film surface so that the abrasion rate was 80 reciprocations / min and the coating film surface was abraded 1,000 times with a stroke length of 140 mm. The abrasion rate was 80 reciprocations / min and the coating film surface was abraded 1,000 times with a stroke length of 140 mm. The abrasion rate was then visually observed. If there were no scratches, the coating film surface was rated A; if there were less than 20 scratches, the coating film surface was rated B; and if there were 20 or more scratches or peeling, the coating film surface was rated C.

[0138]

[0139] Details of each component listed in Table 1 other than those mentioned above are shown below. Silica A: acryloyl group-modified silica (average particle size 12 nm) Silica B: epoxy group-modified silica (average particle size 12 nm) Epoxy: 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate Acrylic A: 1,6-hexanediol diacrylate Acrylic B: difunctional urethane acrylate (weight average molecular weight 1,600) Acrylic C: trifunctional urethane acrylate having a hexamethylene diisocyanate skeleton (weight average molecular weight 940) Acrylic D: polyethylene glycol (n≈4) diacrylate Acrylic E: polyethylene glycol (n=9) diacrylate Acrylic F: isocyanuric acid ethylene oxide-modified di- and triacrylate Acrylic G: pentaerythritol tri- and tetraacrylate

[0140] The coating film of Comparative Example 2 was brittle, and in the scratch resistance evaluation, many scratches and peeling occurred after less than 100 abrasions.

[0141] As shown in Table 1, the coating compositions of Examples 1 to 24 provided coating films with excellent scratch resistance compared to Comparative Examples 1 to 6. Furthermore, the coating compositions of Examples 1 to 11 and 15 to 24 provided coating films with excellent continuous flex resistance and hardness.

[0142] The disclosure of Japanese Patent Application No. 2024-69329, filed on April 22, 2024, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A coating composition containing a compound represented by the following formula (1): In formula (1), R １ ~R ３ each independently represents a hydrogen atom or a monovalent organic group, a to d represent a molar ratio, a and b each independently represent a positive number, and c and d each independently represent 0 or a positive number.

2. The above R １ The coating composition according to claim 1, wherein a / b contains a group having a polymerizable functional group and satisfies 0.4<a / b<1.

5.

3. The coating composition according to claim 1, which is capable of forming a film having an average indentation hardness of 0.40 GPa or more at a surface depth of 200 nm to 400 nm as measured with a nanoindenter.

4. The coating composition according to claim 1, further comprising inorganic particles and a polymerization initiator.

5. The coating composition according to claim 4, wherein the inorganic particles have an average particle size of less than 1 μm.

6. The coating composition according to claim 4, wherein the inorganic particles are silica particles.

7. The coating composition according to claim 4, wherein the mass ratio of the inorganic particles in the coating composition excluding the solvent and the polymerization initiator is 50 mass % or less.

8. The coating composition according to claim 1, further comprising a di- or higher functional (meth)acrylate compound or a di- or higher functional epoxy compound.

9. The coating composition according to claim 8, wherein the mass ratio of the di- or higher functional (meth)acrylate compound or the di- or higher functional epoxy compound in the coating composition excluding the solvent and the polymerization initiator is greater than 0 mass % and less than 35 mass %.

10. The coating composition according to claim 1, wherein a film having a thickness of less than 10 μm obtained by curing the coating composition does not break even when bent continuously inward 200,000 times at a bending radius R of 1.5 mm.

11. A coating film obtained by curing the coating composition according to any one of claims 1 to 10.

12. A substrate provided with the coating film according to claim 11.

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