Hard coat layer-forming composition and spectacle lens

Abstract

The present invention provides a hard coat layer-forming composition from which it is possible to form a hard coat layer that exhibits excellent adhesiveness. A hard coat layer-forming composition according to the present invention comprises: at least one selected from the group consisting of hydrolyzable silicon compounds, hydrolysates thereof, and hydrolysis condensates thereof; a silsesquioxane compound having an oxetanyl group; a cationic polymerization initiator; and two or more hydroxybenzophenone compounds having different numbers of hydroxy groups.

Description

Composition for forming a hard coat layer, eyeglass lenses

[0001] This disclosure relates to a composition for forming a hard coat layer and to eyeglass lenses.

[0002] In eyeglass lenses used in eyeglasses, lenses with a hard coat layer formed on the surface of the lens substrate are widely used. As a coating composition for forming such a hard coat layer, for example, Patent Document 1 discloses a coating composition containing fine particles of a composite oxide of titanium dioxide and zirconium oxide, and an organosilicon compound or its hydrolysate, and the specification further describes a coating composition containing a metal complex compound.

[0003] Japanese Patent Application Publication No. 07-168002

[0004] This disclosure relates to a hard coat layer forming composition comprising at least one selected from the group consisting of hydrolyzable silicon compounds, their hydrolysates, and their hydrolyzate condensates; a silsesquioxane compound having an oxetanyl group; a cationic polymerization initiator; and two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups.

[0005] The present disclosure is described in detail below. The hard coat layer forming composition of this disclosure can form a hard coat layer with excellent adhesion. In this disclosure, "excellent adhesion" means that the hard coat layer formed using the above composition can maintain a certain level of adhesion even after being exposed to an ultraviolet environment for a certain period of time. The following descriptions of constituent elements may be based on typical embodiments of this disclosure, but this disclosure is not limited to such embodiments.

[0006] In this specification, a numerical range expressed using "~" means a range that includes the numbers written before and after "~" as the lower and upper limits. Also in this specification, if there are two or more types of a component, the "content" of that component means the total content of those two or more types of components. In this specification, in numerical ranges described in steps, the upper or lower limit stated in one numerical range may be replaced with the upper or lower limit of another numerical range described in steps. Also, in numerical ranges described in this specification, the upper or lower limit stated in one numerical range may be replaced with the value shown in the example. In this specification, a combination of two or more preferred embodiments is a more preferred embodiment.

[0007] In this specification, "solids" of a composition means the components that form the layer formed using the composition, and if the composition contains a solvent (e.g., an organic solvent and water), it means all components excluding the solvent. Furthermore, liquid components that form the layer formed using the composition are also considered to be solids.

[0008] In this specification, the bonding direction of divalent groups is not limited unless otherwise specified. For example, in a compound represented by the formula "X-Y-Z", if Y is -COO-, Y may also be -CO-O- or -O-CO-. Furthermore, the above compound may also be "X-CO-O-Z" or "X-O-CO-Z". In this specification, unless otherwise specified, when there are multiple substituents and linking groups etc. (hereinafter referred to as substituents etc.) indicated by a specific symbol, or when multiple substituents etc. are specified simultaneously, it means that each substituent etc. may be the same as or different from one another. The same applies to the specification of the number of substituents etc.

[0009] [Composition for forming a hard coat layer] The composition for forming a hard coat layer comprises at least one selected from the group consisting of hydrolyzable silicon compounds, their hydrolysates, and their hydrolyzed condensates, a silsesquioxane compound having an oxetanyl group, a cationic polymerization initiator, and two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups. The following describes in detail each component of the composition for forming a hard coat layer.

[0010] [Two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups] The hard coat layer forming composition contains two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups. The hard coat layer is preferably one in which physical properties such as color tone and strength do not change easily even in an ultraviolet environment, and as one means of suppressing the change in the above physical properties, an ultraviolet absorber may be used. An ultraviolet absorber is a compound that absorbs ultraviolet light having a wavelength of 400 nm or less and does not decompose itself but remains in a stable form, for example, a form that releases the absorbed energy as thermal energy. In the hard coat layer forming composition of this disclosure, two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups are thought to function as ultraviolet absorbers in the composition, but when the inventors used only one type of hydroxybenzophenone, the adhesion of the resulting hard coat layer (adhesion after exposure to ultraviolet light) was insufficient. Herein, as a result of various studies conducted by the inventors, it was surprisingly revealed that the adhesion was excellent when two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups were included.

[0011] As described above, hydroxybenzophenone compounds are thought to function as ultraviolet absorbers in the composition. Among two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups, the hydroxybenzophenone compound whose maximum absorption wavelength is in the shortest wavelength region preferably has a maximum absorption wavelength in the range of 270 to 310 nm. Furthermore, among two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups, the hydroxybenzophenone compound whose maximum absorption wavelength is in the longest wavelength region preferably has a maximum absorption wavelength in the range of 330 to 370 nm.

[0012] The number of hydroxyl groups in the above-mentioned hydroxybenzophenone compound is not particularly limited, but 1 to 6 is preferred, 2 to 6 is more preferred, and 2 to 4 is even more preferred. In particular, it is preferable that each of the two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups has 2 to 4 hydroxyl groups, and it is more preferable that at least one of the two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups has 2 hydroxyl groups and at least one has 4 hydroxyl groups.

[0013] Among the two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups, compounds represented by the following formula (X) are preferred, and compounds represented by the following formula (X1) or the following formula (X2) are more preferred. In particular, among the two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups, it is even more preferable that at least one is a compound represented by the following formula (X1) and at least one is a compound represented by the following formula (X2).

[0014]

[0015] In formula (X), R ａ R represents a hydroxyl group, alkyl group, or alkoxy group. ｂrepresents an alkyl group or an alkoxy group. The above alkyl group may be linear, branched or cyclic, but linear or branched is preferred. The number of carbon atoms in the above alkyl group is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4. The above alkoxy group may be linear, branched or cyclic, but linear or branched is preferred. The number of carbon atoms in the above alkoxy group is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4. R ａ is preferably a hydroxy group, and R ｂ is preferably an alkoxy group.

[0016] In the above formula (X), n represents an integer of 1 to 5, and p and k each independently represent an integer of 0 to 5. However, n + k = 5. n is preferably 1 to 3, more preferably 1 or 2, and even more preferably 2. p is preferably 0 to 2, more preferably 0 or 1. k is preferably 0 or 1, more preferably 0.

[0017] In the above formula (X1) and the above formula (X2), n1 to n3 each independently represent an integer of 1 to 5. n1 is preferably 1 to 3, more preferably 2 to 3, and even more preferably 2. n2 is preferably 1 to 3, more preferably 2 to 3, and even more preferably 2. n3 is preferably 1 to 3, more preferably 2 to 3, and even more preferably 2.

[0018] The compound represented by the above formula (X1) is preferably a compound represented by the formula (X1a), and the compound represented by the above formula (X2) is preferably a compound represented by the formula (X2a).

[0019]

[0020] In the formula (X1a) and the formula (X2a), m1 to m3 each independently represent an integer of 1 to 4. m1 is preferably 1 or 2, more preferably 1. m2 is preferably 1 or 2, more preferably 1. m3 is preferably 1 or 2, more preferably 1.

[0021] Specific examples of hydroxybenzophenone compounds include hydroxybenzophenones selected from the group consisting of 2,4-dihydroxybenzophenone, 2,2′,4,4′-tetrahydroxybenzophenone, 2-hydroxybenzophenone, 2,2′-dihydroxybenzophenone, 2,4,4′-trihydroxybenzophenone, 2,3,4,4′-tetrahydroxybenzophenone, 2,3′,4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4′-methylbenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, and 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, and it is preferable that two or more compounds with different numbers of hydroxyl groups are selected from the above group.

[0022] The hard coat layer forming composition may contain three or more hydroxybenzophenone compounds having different numbers of hydroxyl groups, but it is preferable to contain two hydroxybenzophenone compounds having different numbers of hydroxyl groups. The total content of hydroxybenzophenone compounds in the hard coat layer forming composition is not particularly limited, but it is preferably 0.1 to 10% by mass, and more preferably 0.5 to 2% by mass, relative to the total solid content in the hard coat layer forming composition. Furthermore, if the hydroxybenzophenone compound with the fewest number of hydroxyl groups among the two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups is designated as HBP-X and the hydroxybenzophenone compound with the most hydroxyl groups is designated as HBP-Y, then the mass ratio of the content of HBP-X to the content of HBP-Y (HBP-X / HBP-Y) is preferably 0.1 to 4.0, and more preferably 1.0 to 3.5. Furthermore, the content of HBP-X is not particularly limited, but is preferably 0.1 to 5% by mass, and more preferably 0.3 to 5% by mass, relative to the total solid content in the hard coat layer forming composition. Furthermore, the content of HBP-Y is not particularly limited, but is preferably 0.01 to 5% by mass, and more preferably 0.05 to 1.0% by mass, relative to the total solid content in the hard coat layer forming composition.

[0023] [At least one selected from the group consisting of hydrolyzable silicon compounds, their hydrolysates, and their hydrolyzed condensates] The hard coat layer forming composition contains at least one selected from the group consisting of hydrolyzable silicon compounds, their hydrolysates, and their hydrolyzed condensates (hereinafter also simply referred to as "hydrolyzable silicon compounds"). A hydrolyzable silicon compound is a compound in which a hydrolyzable group is bonded to a silicon atom. A hydrolyzable silicon compound refers to a compound obtained by hydrolyzing the hydrolyzable group in the hydrolyzable silicon compound. The hydrolyzable compound may be one in which all of the hydrolyzable groups have been hydrolyzed (complete hydrolyzate) or one in which only a part of the hydrolyzable groups have been hydrolyzed (partial hydrolyzate). In other words, the hydrolyzable compound may be a complete hydrolyzate, a partial hydrolyzate, or a mixture thereof. Furthermore, a hydrolyzed condensate of a hydrolyzable silicon compound refers to a compound obtained by hydrolyzing the hydrolyzable group in the hydrolyzable silicon compound and condensing the resulting hydrolyzates. Furthermore, the hydrolysis condensate described above may be a product in which all hydrolyzable groups are hydrolyzed and all hydrolyzed products are condensed (a completely hydrolyzed condensate), or a product in which some hydrolyzable groups are hydrolyzed and some hydrolyzed products are condensed (a partially hydrolyzed condensate). In other words, the hydrolysis condensate described above may be a completely hydrolyzed condensate, a partially hydrolyzed condensate, or a mixture thereof.

[0024] A hydrolyzable group is a group that is directly bonded to a silicon atom (Si) and can undergo at least one of a hydrolysis reaction and a condensation reaction. Examples of hydrolyzable groups include alkoxy groups, hydroxyl groups, halogen atoms, acyloxy groups, alkenyloxy groups, and isocyanate groups, with alkoxy groups being preferred.

[0025] The hard coat layer forming composition preferably contains a hydrolyzable silicon compound represented by formula (1). Formula (1) X-L-Si(R １ ) ｎ (R ２ ) ３－ｎ In formula (1), X represents an epoxy group. An epoxy group is a group represented by the following formula: R３ represents a hydrogen atom or an alkyl group (e.g., methyl group, ethyl group, and propyl group). * represents the bonding position.

[0026]

[0027] In the above formula (1), L represents a divalent hydrocarbon group which may contain a heteroatom. The number of carbon atoms in the hydrocarbon group is not particularly limited, and 1 to 10 is preferable. Examples of the divalent hydrocarbon group include an alkylene group, an alkenylene group, an alkynylene group, an arylene group, and combinations of these groups, and an alkylene group which may contain a heteroatom is preferable. R １ represents a hydrolyzable group. Specific examples of the hydrolyzable group are as described above, and among them, an alkyl group having 1 to 3 carbon atoms is preferable. R ２ represents an alkyl group. The number of carbon atoms in the alkyl group is preferably 1 to 10. n represents an integer of 1 to 3. n is preferably 3.

[0028] The hydrolyzable silicon compound may be used alone or in combination of two or more. The content of the hydrolyzable silicon compounds in the composition for forming the hard coat layer is not particularly limited, but is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, based on the total solid content in the composition for forming the hard coat layer. In this specification, when calculating the content of the hydrolyzable silicon compounds, for convenience, it is calculated based on the mass of the compound before hydrolysis.

[0029] [Silsesquioxane compound having an oxetanyl group] The composition for forming the hard coat layer contains a silsesquioxane compound having an oxetanyl group. The silsesquioxane compound is generally a silane compound having a basic skeleton represented by the following formula (2), which is obtained by hydrolyzing a trifunctional silane compound such as alkoxysilane, chlorosilane, and silanol. In the following formula (2), R ｄ represents an organic group. Formula (2) R ｄ -SiO ３／２

[0030] In addition to the irregular form known as the random structure, silsesquioxane compounds are also known to have ladder structures, cage structures (fully condensed cage structures), and incomplete cage structures (partially cleaved structures of the cage structure, in which some silicon atoms are missing from the cage structure or some silicon-oxygen bonds in the cage structure are broken). The structure of the silsesquioxane compound contained in the hard coat layer forming composition may be any of the above random structures, ladder structures, cage structures, or incomplete cage structures, or it may be a mixture of multiple structures.

[0031] The equivalent amount of oxetanyl groups contained in the silsesquioxane compound is not particularly limited, but 30 to 500 g / eq. is preferred, and 30 to 150 g / eq. is more preferred, in terms of superior hardness of the hard coat layer. The above oxetanyl group is the group represented by the following formula (3). R ２ * represents a hydrogen atom or an alkyl group (e.g., methyl group, ethyl group, and propyl group). * indicates the bond position.

[0032]

[0033] Silsesquioxane compounds having an oxetanyl group may be synthesized by known methods or commercially available products may be used. Examples of commercially available products include OX-SQ TX-100, OX-SQ SI-20, OX-SQ HDX, and OX-SQ ME-20, manufactured by Toagosei Co., Ltd.

[0034] The silsesquioxane compound having an oxetanyl group may be used alone or in combination of two or more. The content of the silsesquioxane compound having an oxetanyl group in the hard coat layer forming composition is not particularly limited, but is preferably 35 to 70% by mass, and more preferably 35 to 60% by mass, relative to the total solid content in the hard coat layer forming composition.

[0035] [Cationic Polymerization Initiator] The hard coat layer forming composition contains a cationic polymerization initiator. Examples of cationic polymerization initiators include thermal cationic polymerization initiators and photocatalytic cationic polymerization initiators. The hard coat layer forming composition preferably contains a thermal cationic polymerization initiator.

[0036] <Thermal Cationic Polymerization Initiators (Thermal Latent Cationic Polymerization Initiators)> Thermal cationic polymerization initiators are compounds that cleave and generate cations when heated to a critical temperature. There are no particular restrictions on the type of thermal cationic polymerization initiator; known thermal cationic polymerization initiators can be used.

[0037] Examples of thermal cationic polymerization initiators include onium salts such as sulfonium salts, anilinium salts, pyridinium salts, toluidinium salts, phosphonium salts, and iodonium salts. These onium salts also contain hexafluorophosphate anions (PF ６ － ), tetrafluoroborate anion (BF ４ － ), hexafluoroantimonate anion (SbF ６ － ), and hexafluoroarsenate anion (AsF ６ － It contains anions (negative ions) such as ). Examples of commercially available thermal cationic polymerization initiators include ADEKA's ADEKA Optron CP-66.

[0038] <Photocationic polymerization initiators> Photocationic polymerization initiators are compounds that generate cations when irradiated with light such as visible light or ultraviolet light. There are no particular restrictions on the type of photocationic polymerization initiator, and known photocationic polymerization initiators can be used.

[0039] Examples of photocationic polymerization initiators include onium salts such as iodonium salts (e.g., aromatic iodonium salts) and sulfonium salts (e.g., aromatic sulfonium salts), halogen-containing compounds such as s-triazine derivatives, sulfone compounds, sulfonic acid compounds, sulfonimide compounds, and diazomethane compounds. Among these, aromatic sulfonium salts are preferred as photocationic polymerization initiators.

[0040] As aromatic sulfonium salts, compounds having a triarylsulfonium cation and anion are preferred. Examples of triarylsulfonium cations include triphenylsulfonium cations having alkyl groups, thioether groups, or ether groups as substituents. Specific examples of triarylsulfonium cations include diphenyl[4-(phenylthio)phenyl]sulfonium cation, triphenylsulfonium cation, and alkyltriphenylsulfonium cation. As anions, hexafluorophosphate anions (PF ６ － ), hexafluoroantimonate anion (SbF ６ － ), pentafluorohydroxyantimonate anion (SbF ５ (OH) － ), hexafluoroarsenate anion (AsF ６ － ), tetrafluoroborate anion (BF ４ － ), and tetrakis(pentafluorophenyl) borate anion (B(C) ６ F ５ ) ４ － Examples include the following. Commercial aromatic sulfonium salts include ADEKA's ADEKA optomer SP-150, SP-170, SP-171, etc.

[0041] The cationic polymerization initiator may be used alone or in combination of two or more. The content of the cationic polymerization initiator in the hard coat layer forming composition is not particularly limited, but it is preferably 0.1 to 6% by mass, and more preferably 0.2 to 3% by mass, relative to the total solid content in the hard coat layer forming composition.

[0042] [Metal Oxide Particles] The hard coat layer forming composition preferably further contains metal oxide particles. The type of metal oxide particles is not particularly limited and known metal oxide particles can be cited. Examples of metal oxide particles include oxide particles of at least one metal selected from Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, Zr, In, and Ti. Among these, in terms of ease of handling, oxide particles containing Si (silicon oxide particles), oxide particles containing Sn (tin oxide particles), oxide particles containing Zr (zirconium oxide particles), or oxide particles containing Ti (titanium oxide particles) are preferred as metal oxide particles. The metal oxide particles may contain only one type of metal (metal atom) as exemplified above, or they may contain two or more types of metals (metal atoms). Although Si (silicon) is sometimes classified as a metalloid, in this specification Si is included as a metal.

[0043] The average particle size of the metal oxide particles is not particularly limited, but is preferably 1 to 200 nm, and more preferably 5 to 30 nm. Within this range, the dispersion stability of the metal oxide particles in the hard coat layer forming composition is better, and the whitening of the cured product can be further suppressed. The average particle size is determined by measuring the diameters of 100 or more metal oxide particles using a transmission electron microscope and taking their arithmetic mean. If the metal oxide particles are not perfectly round, the major axis is used as the diameter.

[0044] Various functional groups may be introduced to the surface of the metal oxide particles, as needed.

[0045] The metal oxide particles may be used individually or in combination of two or more types. The content of metal oxide particles in the hard coat layer forming composition is not particularly limited, but it is preferably 25 to 60% by mass, and more preferably 35 to 50% by mass, relative to the total solid content in the hard coat layer forming composition.

[0046] [Solvent] The composition for forming the hard coat layer preferably contains a solvent. The solvent is not particularly limited and may be water or an organic solvent. Examples of organic solvents include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, amide-based solvents, sulfone-based solvents, and sulfoxide-based solvents.

[0047] As the alcohol-based solvent, an alcohol-based solvent having 10 or fewer carbon atoms is preferred, and an alcohol-based solvent having 5 or fewer carbon atoms (for example, isopropanol) is more preferred. The alcohol-based solvent may also be a polyhydric alcohol having two or more hydroxyl groups in one molecule. Examples of alcohol-based solvents include methanol, ethanol, isopropanol, n-butanol, t-butanol, isobutyl alcohol, pentanol, hexanol, propylene glycol, ethylene glycol, diethylene glycol, 2-methyl-1,3-propanediol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, and 1,4-butanediol.

[0048] The solvent may be used alone or in combination of two or more types. The total solid content in the hard coat layer forming composition is preferably 10 to 90% by mass, and more preferably 40 to 80% by mass, based on the total mass of the hard coat layer forming composition.

[0049] The hard coat layer forming composition may optionally contain various additives such as compounds having multiple epoxy groups, polymerizable monomers, polymerization initiators (e.g., radical polymerization initiators), ultraviolet absorbers, light stabilizers, antioxidants, anti-aging agents, surfactants, coating modifiers, color inhibitors, dyes, fillers, internal mold release agents, rust inhibitors, fungicides, antibacterial agents, anti-bacterial agents, deodorants, pigments, flame retardants, and antistatic agents. However, these components are intended to be components other than the specific benzophenones, hydrolyzable silicon compounds, silsesquioxane compounds having oxetanyl groups, cationic polymerization initiators, metal oxide particles, and solvents mentioned above.

[0050] <Compounds Having Multiple Epoxy Groups> The hard coat layer forming composition may contain compounds having multiple epoxy groups (hereinafter also simply referred to as "polyfunctional epoxy compounds"). Since the epoxy groups in polyfunctional epoxy compounds are easily ring-opened by cations, they contribute to promoting the initial reaction of polymerization during the curing treatment described later. Polyfunctional epoxy compounds contain multiple epoxy groups (two or more). The number of epoxy groups is not particularly limited, but 2 to 6 is preferred, and 2 to 3 is more preferred. An epoxy group is a group represented by the following formula: R １ * represents a hydrogen atom or an alkyl group (e.g., methyl group, ethyl group, and propyl group). * indicates the bond position.

[0051]

[0052] The type of polyfunctional epoxy compound is not particularly limited, and known polyfunctional epoxy compounds can be used, such as aliphatic glycidyl ether type epoxy compounds, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, phenol novolac type epoxy compounds, and cresol novolac type epoxy compounds. Among the polyfunctional epoxy compounds, compounds represented by formula (4) are preferred.

[0053]

[0054] L １ L represents an n-valent hydrocarbon group which may contain an oxygen atom. The number of carbon atoms in the hydrocarbon group is not particularly limited, but from the viewpoint of handling the polyfunctional epoxy compound, 3 to 30 is preferred, and 3 to 10 is more preferred. The hydrocarbon group may be linear, branched, cyclic, or a combination of these structures. Furthermore, the hydrocarbon group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination of these. n represents 2 or more, and from the viewpoint of handling the polyfunctional epoxy compound, 2 to 6 is preferred, and 2 to 3 is more preferred. For example, when n is 2, L represents a divalent hydrocarbon group which may contain an oxygen atom (for example, an alkylene group which may contain an oxygen atom). １represents a hydrogen atom or an alkyl group (e.g., a methyl group, an ethyl group, and a propyl group).

[0055] More specifically, the compounds represented by formula (4) above include aliphatic glycidyl ether type epoxy compounds obtained by the reaction of at least one selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, polypropylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, polybutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, glycerol, diglycerol, polyglycerol, trimethylolpropane, pentaerythritol, sorbitol, and arabitol with epichlorohydrin.

[0056] The polyfunctional epoxy compound may be used alone or in combination of two or more. The content of the polyfunctional epoxy compound in the hard coat layer forming composition is not particularly limited, but is preferably 1 to 15% by mass, and more preferably 1 to 10% by mass, relative to the total solid content in the hard coat layer forming composition.

[0057] <Polymerizable Monomers> Polymerizable monomers are compounds that have polymerizable groups. Examples of polymerizable monomers include compounds that have radical polymerizable groups and compounds that have cationic polymerizable groups. In polymerizable monomers, the number of polymerizable groups is preferably 2 to 6, and more preferably 2 to 3.

[0058] As the compound having the radical polymerizable group described above, (meth)acrylate compounds are preferred. The term (meth)acrylate compound refers to a concept that includes compounds containing a methacryloyl group and compounds containing an acryloyl group. The (meth)acrylate compound is preferably a polyfunctional (meth)acrylate compound having two or more radical polymerizable groups (methacryloyl groups or acryloyl groups) in its molecule, and the preferred number of polymerizable groups is as described above. Furthermore, the (meth)acrylate compound may also be a compound having a group selected from the group consisting of a phosphoric acid group and a sulfonic acid group.

[0059] As a polyfunctional (meth)acrylate, the compound represented by formula (E) is preferred. Formula (E) CH ２ =CR ｅ１ -CO-L ｅ１ -CO-CR ｅ２ =CH ２ R ｅ１ and R ｅ２ Each of these independently represents either a hydrogen atom or a methyl group. ｅ１ represents a divalent hydrocarbon group which may contain heteroatoms (e.g., oxygen, nitrogen, or sulfur atoms). The number of carbon atoms in the divalent hydrocarbon group is not particularly limited, but 1 to 10 is preferred. Examples of divalent hydrocarbon groups include alkylene groups, alkenylene groups, alkyline groups, arylene groups, and combinations thereof, which may contain heteroatoms, with alkylene groups which may contain heteroatoms being preferred. Among these, alkylene groups containing oxygen atoms are preferred, and -O-(L ｅ２ -O) ｒ A group represented by - is preferred. ｅ２ represents an alkylene group (preferably with 1 to 3 carbon atoms). r represents an integer of 1 or more, preferably an integer between 1 and 10, and more preferably an integer between 2 and 5.

[0060] [Physical Properties of the Composition for Forming a Hard Coat Layer] The viscosity of the composition for forming a hard coat layer at 25°C is preferably 1 mPa·s or more, more preferably 3 mPa·s or more, and even more preferably 5 mPa·s or more, in terms of film thickness. The upper limit of the viscosity of the composition for forming a hard coat layer at 25°C is preferably 30 mPa·s or less, and more preferably 20 mPa·s or less, in terms of coating ability. The above viscosity can be measured using a known measuring device (for example, a cone-plate viscometer).

[0061] [Method for Manufacturing a Hard Coat Layer Forming Composition] The method for manufacturing a hard coat layer forming composition is not particularly limited and can be manufactured by known methods. Specifically, for example, a method of mixing the above components can be used. The mixing order of the above components is not particularly limited, but for example, hydrolyzable silicon compounds, cationic polymerization initiators, two or more hydroxybenzophenone compounds, and other optional components (for example, surfactants) can be added to a composition obtained by mixing a silsesquioxane compound having an oxetanyl group and other optional components (for example, a solvent and metal oxide particles). More specifically, a method of mixing the above components can be used by adding each component sequentially and then stirring to mix them. When adding each component, it may be added all at once or in multiple steps. Heat treatment may also be performed as needed. It is preferable to mix the above components immediately before film formation.

[0062] [Hard Coat Layer] The hard coat layer forming composition of this disclosure can form a hard coat layer with excellent adhesion. Preferably, the hard coat layer contains cured products of various components other than the solvent contained in the composition. A method for manufacturing the hard coat layer is to cure a coating film of the composition. More specifically, a method for curing a coating film of the composition is to apply the composition to a desired member to form a coating film, and then apply predetermined treatments such as drying and curing to the coating film as necessary to form a hard coat layer. From the viewpoint of uniformity of the formed hard coat layer, it is preferable to form a coating film of a composition containing a solvent and then perform a drying treatment to remove the solvent. The curing treatment may be performed simultaneously with the drying treatment, or the drying treatment may also serve as the curing treatment. Examples of methods for applying the composition include dipping coating, spin coating, spray coating, inkjet coating, and flow coating.

[0063] The above drying treatment is not particularly limited as long as it is a method for removing the solvent contained in the hard coat layer forming composition, and may be, for example, natural drying, a method of supplying dry air, or heat drying. The heating temperature during the drying treatment is preferably 30 to 90°C, and more preferably 40 to 85°C. The drying time is preferably 1 minute to 3 hours, and more preferably 5 minutes to 2 hours.

[0064] The above curing treatment can be appropriately selected depending on the components contained in the hard coat layer forming composition, but examples include heat treatment and light irradiation treatment. The temperature in the heat treatment should be such that the substrate for forming the hard coat layer does not deform, for example, 30 to 120°C, preferably 40 to 120°C, and more preferably 90 to 105°C. The drying time should be such that 30 seconds to 360 minutes, preferably 30 minutes to 90 minutes. The light used in the light irradiation treatment is not particularly limited, but examples include ultraviolet light and visible light. A high-pressure mercury lamp can be used as the light source. The cumulative light intensity in the light irradiation treatment is not particularly limited, but should be 100 to 3000 mJ / cm². ２ Preferably, 100 to 1500 mJ / cm² ２This is preferable.

[0065] [Eyeglass Lens] The eyeglass lens of this disclosure comprises an eyeglass lens substrate and a hard coat layer formed using the hard coat layer forming composition of this disclosure. The eyeglass lens may have layers other than the hard coat layer. Examples of layers other than the hard coat layer include an anti-reflective layer, a water- and oil-repellent layer, an anti-fouling layer, and an anti-fog layer, and it is preferable to have at least one of the anti-reflective layer and the water- and oil-repellent layer. The eyeglass lens may have each of the above layers on one surface of the eyeglass lens substrate or on both surfaces. Furthermore, there are no particular restrictions on the order in which the layers are arranged, but it is preferable to have the eyeglass lens substrate, primer layer, hard coat layer, anti-reflective layer, and water- and oil-repellent layer in this order.

[0066] [Eyeglass Lens Substrate] There are no particular restrictions on the type of eyeglass lens substrate, but examples include finished lenses in which both the convex and concave surfaces are optically finished and molded to the desired prescription, semi-finished lenses in which only the convex surface is finished as an optical surface (spherical, rotationally symmetric aspherical, progressive, etc.), and semi-finished lenses in which the concave surface is processed and polished according to the wearer's prescription.

[0067] The thickness of the spectacle lens base material is preferably 0.8 to 30.0 mm, and more preferably 1.0 to 10.0 mm, from the standpoint of ease of handling. The refractive index of the spectacle lens base material is preferably 1.50 or higher, more preferably 1.60 to 1.80, and even more preferably 1.60 to 1.74.

[0068] The material of the spectacle lens substrate is not particularly limited, and examples include glass spectacle lens substrates and plastic spectacle lens substrates made of organic materials, with plastic spectacle lens substrates being preferred. Examples of glass spectacle lens substrates include inorganic glass lenses.

[0069] The type of plastic (so-called resin) included in the above-mentioned plastic eyeglass lens substrate is not particularly limited, but examples include (meth)acrylic acid ester resin, thiourethane resin, allyl resin, episulfide resin, polycarbonate resin, urethane resin, polyester resin, polystyrene resin, polyethersulfone resin, poly-4-methylpentene-1 resin, and diethylene glycol bisallyl carbonate resin (CR-39). Among these, thiourethane resin, episulfide resin, or diethylene glycol bisallyl carbonate resin is preferred. The thiourethane resin is obtained from a polyisocyanate compound and a polythiol compound. As the polyisocyanate compound, it is preferable to use at least one selected from m-xylylene diisocyanate, a mixture of 2,5-bis(isocyanatomethyl)-bicyclo[2,2,1]heptane and 2,6-bis(isocyanatomethyl)-bicyclo[2,2,1]-heptane, isophorone diisocyanate, hexamethylene diisocyanate, and tolylene diisocyanate. Preferred polythiol compounds include pentaerythritol tetrakis(3-mercaptopropionate), 1,2-bis[(2-mercaptoethyl)thio]-3-mercaptopropane, or a mixture of 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane. The episulfide resin is a resin obtained by ring-opening polymerization of a monomer having an episulfide group (epithio group), or a mixed monomer containing such monomer. As the monomer having an episulfide group, it is preferable to use at least one selected from bis(2,3-epithiopropyl)sulfide and bis(2,3-epithiopropyl)disulfide.

[0070] The spectacle lens substrate is preferably light-transmitting and may be either transparent or opaque, or it may be colored. The spectacle lens substrate may also contain additives such as bluing agents, light stabilizers, ultraviolet absorbers, and antioxidants.

[0071] [Primer Layer] The primer layer improves the adhesion of the hard coat layer formed using the hard coat layer forming composition to the spectacle lens substrate, thereby imparting impact resistance to the resulting lens. It is preferable to place the primer layer between the spectacle lens substrate and the hard coat layer described later. The material constituting the primer layer is not particularly limited, and known materials can be used, for example, mainly resins are used. The type of resin used is not particularly limited, and examples include polyurethane resin, polyester resin, and polyvinyl alcohol, with polyurethane resin being preferred.

[0072] The primer layer may contain components other than the resin described above. Examples of other components include oxide fine particles of at least one metal selected from Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, Zr, In, and Ti, or composite oxide fine particles thereof, hydrolyzable silicon compounds and / or hydrolyzable condensates thereof, and surfactants.

[0073] The method for forming the primer layer is not particularly limited, and known methods can be employed. For example, a method can be used in which a primer layer-forming composition containing a predetermined resin is applied to an eyeglass lens substrate, and a curing treatment is performed as necessary to form the primer layer. The method for applying the primer layer-forming composition is not particularly limited, and an example can be given in which a method for applying the subsequent hard coat layer-forming composition to the substrate is used. The thickness of the primer layer is not particularly limited, but 0.3 to 2 μm is preferred.

[0074] [Hard Coat Layer] As the hard coat layer, a hard coat layer formed using the hard coat layer forming composition of this disclosure is used. The hard coat layer is preferably placed on the primer layer, and more preferably placed between the primer layer and the anti-reflective layer. The hard coat layer preferably exhibits a hardness of H or higher on the pencil hardness scale according to JIS K5600. The thickness of the hard coat layer is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 5 μm or more, and particularly preferably 10 μm or more. The upper limit of the thickness is preferably 30 μm or less, and more preferably 20 μm or less.

[0075] [Anti-reflective layer] The anti-reflective layer may be a single-layer or multi-layer structure. An inorganic anti-reflective layer is preferred as the anti-reflective layer. An inorganic anti-reflective layer means an anti-reflective layer composed of an inorganic compound. A multi-layer anti-reflective layer may have a structure in which low refractive index layers and high refractive index layers are alternately stacked. Examples of materials constituting the high refractive index layer include metal oxides selected from titanium, zirconium, aluminum, niobium, tantalum, and lanthanum. Examples of materials constituting the low refractive index layer include silicon oxide.

[0076] Methods for forming an anti-reflective layer include, for example, dry methods such as vacuum deposition, sputtering, ion plating, ion beam-assisted deposition, and CVD.

[0077] The thickness of the anti-reflective layer is preferably 100 to 10,000 nm, and more preferably 300 to 800 nm.

[0078] [Water- and oil-repellent layer] The water- and oil-repellent layer is preferably placed on the outermost layer of the spectacle lens. The water- and oil-repellent layer reduces the surface energy of the spectacle lens, improving its ability to prevent contamination, and also improves the slipperiness of the surface of the spectacle lens, thereby improving the abrasion resistance of the spectacle lens.

[0079] The materials constituting the water-repellent and oil-repellent layer are not particularly limited, and examples include fluorine-containing compounds (compounds containing fluorine atoms) and silicon-containing compounds (compounds containing silicon atoms). In particular, the water-repellent and oil-repellent layer preferably contains a fluorine-containing compound, and more preferably contains at least one selected from the group consisting of fluorine-substituted alkyl group-containing organosilicon compounds, their hydrolysates, and their hydrolyzed condensates. The materials constituting the water-repellent and oil-repellent layer may be used individually or in combination of two or more.

[0080] A fluorine-substituted alkyl group-containing organosilicon compound is an organosilicon compound containing an alkyl group in which some or all of the hydrogen atoms are substituted with fluorine atoms, and which has a hydrolyzable group. Here, a hydrolyzable group is a group that is directly bonded to a silicon atom and can proceed with hydrolysis and condensation reactions, and examples include alkoxy groups, halogen atoms, acyloxy groups, alkenyloxy groups, and isocyanate groups. Note that if multiple hydrolyzable groups are directly bonded to a single silicon atom, they may be the same or different.

[0081] A hydrolysate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in the fluorine-substituted alkyl group-containing organosilicon compound. The hydrolysate may be a complete hydrolysate (where all hydrolyzable groups are hydrolyzed) or a partial hydrolysate (where only some hydrolyzable groups are hydrolyzed). In other words, the hydrolysate may be a complete hydrolysate, a partial hydrolysate, or a mixture thereof. A hydrolysis condensate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in the fluorine-substituted alkyl group-containing organosilicon compound and condensing the resulting hydrolysates. The hydrolysis condensate may be a complete hydrolysis condensate (where all hydrolyzable groups are hydrolyzed and all hydrolysates are condensed) or a partial hydrolysis condensate (where some hydrolyzable groups are hydrolyzed and some hydrolysates are condensed). In other words, the hydrolysis condensate may be a complete hydrolysis condensate, a partial hydrolysis condensate, or a mixture thereof.

[0082] The thickness of the water-repellent and oil-repellent layer is not particularly limited, but 5 to 35 nm is preferred.

[0083] The method for forming the water-repellent and oil-repellent layer is not particularly limited and can be arbitrarily selected depending on the materials used, desired performance, or thickness. For example, a method in which a water-repellent and oil-repellent layer-forming composition containing a fluorine-substituted alkyl group-containing organosilicon compound is applied to a substrate and cured as necessary, and a dry method are mentioned. Examples of application methods include dipping coat, roll coat, bar coat, spin coat, spray coat, die coat, and gravure coat. Examples of curing treatments include light irradiation, heat treatment, and steam contact treatment. Steam contact treatment, for example, is a treatment in which the material is brought into contact with air whose humidity is controlled to 50-90% RH. The above curing treatments may be performed in combination. An example of a dry method is the same as that for the anti-reflective layer described above.

[0084] [Method for Manufacturing Eyeglass Lenses] Known manufacturing methods can be used for manufacturing eyeglass lenses. Specifically, for example, a method can be used that includes the step of forming a hard coat layer on at least one surface of an eyeglass lens substrate using the hard coat layer forming composition of this disclosure. In particular, a method for manufacturing eyeglass lenses is preferably a method that includes the step of forming a hard coat layer on at least one surface of an eyeglass lens substrate using the hard coat layer forming composition of this disclosure, and the step of forming an anti-reflective layer on the hard coat layer. The method for forming each layer is as described above.

[0085] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited in any way by these examples.

[0086] [Example 1-1] The hard coat layer of Example 1-1 was formed according to the procedure shown below.

[0087] <Preparation of composition for hard coat layer formation (Step 1)> In a glass container equipped with a stirring bar, (A) 27.13 g of cation-curable silsesquioxane (manufactured by Toagosei Co., Ltd.: OX-SQ TX-100) and (B) 90.45 g of colloidal silica (manufactured by JGC Catalysts & Chemicals Inc.: OSCAL-1432E, isopropanol dispersion, solid content 30% by mass) were added as metal oxide particles to form a mixture. The resulting mixture was stirred for 6 hours while being heated on a hot plate set to 160°C. At this time, the glass container was sealed with a lid, and the solvent in the mixture was refluxed.

[0088] <Preparation of composition for hard coat layer formation (Step 2)> ​​After heating was complete, the obtained reaction solution was cooled to room temperature overnight, and then butyl cellosolve (10.85 g) was added to the cooled reaction solution as a solvent for film formation. Next, isopropanol was removed from the reaction solution under reduced pressure at 40°C over 2 hours. Methanol (33.40 g) was added to the obtained crude product to obtain liquid composition X1.

[0089] <Preparation of composition for hard coat layer formation (Step 3)> In a glass container equipped with a stirring bar, add the liquid composition X1 (98.67 g) obtained in Step 2 above, (C) 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-403) (5.32 g) as a hydrolyzable silicon compound, and (D) SbF as a cationic polymerization initiator. ６ － (F) Two or more hydroxybenzophenone compounds with different numbers of hydroxyl groups, such as a benzophenone-based ultraviolet absorber (SEESORB 100 (manufactured by Cipro Chemical Co., Ltd., "SS100", 1% by mass), SEESORB 106 (manufactured by Cipro Chemical Co., Ltd., "SS106", 0.3% by mass)), and (G) a surfactant, such as a polyether-modified silicone (manufactured by Toray Dow Corning Co., Ltd., "DOWSIL L-7001") (0.33 g), were added and mixed to obtain the hard coat layer forming composition of Example 1-1. The content of the above (F) hydroxybenzophenone compounds is the content relative to the total solid content of the hard coat layer forming composition. The structures of SEESORB 100 and SEESORB 106 were as follows.

[0090]

[0091] <Formation of Hard Coat Layer> A lens with a refractive index of 1.74 (Nikon-Essilor Co., Ltd.: Nikon Light 5AS material S-0.00D) was prepared as a plastic spectacle lens substrate. The hard coat layer forming composition of Example 1-1 was applied to one surface of the plastic spectacle lens substrate by spin coating. Specifically, first, 4 mL of the composition was dropped onto the plastic spectacle lens substrate from the center to the outer edge while it was rotating at 300 rpm for 1 second. Next, the plastic spectacle lens substrate coated with the composition was rotated at 300 rpm for 15 seconds, and then the speed was gradually increased to 400 rpm over a further 5 seconds, and it was rotated at that speed for 1 second. Furthermore, the speed was gradually increased to 700 rpm over a further 5 seconds, and it was rotated at that speed for 1 second, and finally, the speed was gradually increased to 2000 rpm over 9.9 seconds, and it was rotated at that speed for 1 second to obtain a plastic spectacle lens substrate with a coating. Next, the obtained coated plastic spectacle lens substrate was heated at 80°C for 20 minutes, and then further heated at the drying temperature of 100°C for 1 hour to form the hard coat layer of Example 1-1 on the plastic spectacle lens substrate. The thickness of the obtained hard coat layer was 15 μm.

[0092] [Examples 1-2 to 1-5, 2-1 to 2-5, and Comparative Examples 1-1 to 1-4, 2-1 to 2-4] (F) The types and compositions of two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups were as shown in Table 1 below, and the drying temperature was set to the value shown in Table 1 above, except that the hard coat layers of each example other than Example 1-1 and the comparative examples were formed in accordance with the procedure described in [Example 1-1].

[0093] [Evaluation] The adhesion of the hard coat layers of each example and comparative example formed using the above procedure was evaluated using the following procedure.

[0094] <Adhesion> The adhesion between the hard coat layer and the lens substrate after exposure to an ultraviolet (UV) environment for a certain period was evaluated by a cross-cut tape test in accordance with JIS-K5600 using the following procedure. For each example and comparative example, the hard coat layer was irradiated with UV light at an illuminance of 60 klx (kilolux) for 200 hours using a SUNTESTER XF-180 (manufactured by Shimadzu Corporation). Then, cuts were made at 1 mm intervals using a knife, reaching the spectacle lens substrate, forming 25 grids. Next, cellophane adhesive tape (manufactured by Nichiban: Cellotape®) was firmly pressed onto the cut hard coat layer, and then the cellophane adhesive tape was quickly pulled off at a 90° angle from the surface to which the tape was attached. After that, the number of peeled grids was counted, and the adhesion was evaluated according to the following evaluation criteria. A small number of peeled grids is preferable, and in practical terms, A or B is preferable.

[0095] (Evaluation Criteria) A: Number of detached squares is 0 B: Number of detached squares is 1 or more and 3 or less C: Number of detached squares is 4 or more and 8 or less D: Number of detached squares is 9 or more

[0096] [Results] Table 1 shows the composition of the hard coat layer forming composition and the results of the adhesion evaluation. The content of two or more hydroxybenzophenone compounds listed in the table indicates the content (by mass) relative to the total solid content of the hard coat layer forming composition. Tinuvin 477 (manufactured by BASF Japan Ltd.), used as a comparative compound, is a hydroxyphenyltriazine (HPT)-based ultraviolet absorber. In the table, "-" indicates that evaluation was not performed.

[0097]

[0098] The evaluation results confirmed that the hard coat layer formed using the hard coat layer forming composition of this disclosure exhibits excellent adhesion.

Claims

1. A composition for forming a hard coat layer, comprising: at least one selected from the group consisting of hydrolyzable silicon compounds, their hydrolysates, and their hydrolyzate condensates; a silsesquioxane compound having an oxetanyl group; a cationic polymerization initiator; and two or more hydroxybenzophenone compounds having different numbers of hydroxyl groups.

2. The hard coat layer forming composition according to claim 1, further comprising metal oxide particles.

3. The hard coat layer forming composition according to claim 1 or 2, wherein at least one of the two or more hydroxybenzophenone compounds is a compound represented by the following formula (X1), and at least one is a compound represented by the following formula (X2). In formulas (X1) and (X2), n1 to n3 each independently represent an integer from 1 to 5.

4. The hard coat layer forming composition according to claim 3, wherein the compound represented by formula (X1) is the compound represented by formula (X1a), and the compound represented by formula (X2) is the compound represented by formula (X2a). In formulas (X1a) and (X2a), m1 to m3 each independently represent an integer from 1 to 4.

5. An eyeglass lens having an eyeglass lens substrate and a hard coat layer formed using the hard coat layer forming composition described in any one of claims 1 to 4.

6. The spectacle lens according to claim 5, further comprising an anti-reflective layer.

7. The spectacle lens according to claim 5 or 6, further comprising a water-repellent and oil-repellent layer.

8. The spectacle lens according to any one of claims 5 to 7, wherein the thickness of the hard coat layer is 10 μm or more.

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