Curable composition for forming protective layer on photochromic article, photochromic article, and eyeglasses

Abstract

Provided is a curable composition for forming a protective layer on a photochromic article that satisfies (1) to (3) below. (1) The composition contains a multifunctional (meth)acrylate having an oxyalkylene structure. (2) The content of the oxyalkylene structure in the solid content of the composition is between 20% and 65% by mass, inclusive. (3) The concentration of (meth)acryloyl groups in the solid content of the composition is between 4.0 mmol / g and 8.0 mmol / g, inclusive.

Description

Curable composition for forming protective layer of photochromic article, photochromic article and eyeglasses

[0001] The present invention relates to a curable composition for forming a protective layer of a photochromic article, a photochromic article, and eyeglasses.

[0002] A photochromic compound is a compound that exhibits a color when irradiated with light in a photoresponsive wavelength range and fades in the absence of light (photochromic property). Hereinafter, an article containing a photochromic compound will be referred to as a photochromic article. For example, Patent Document 1 discloses a photochromic article in which a layer containing a photochromic compound (photochromic layer) is provided on a substrate.

[0003] WO2003 / 011967

[0004] The present inventors have investigated providing a protective layer on a photochromic article with the aim of improving the performance of the photochromic article. Through extensive investigation, the present inventors have concluded that the following performance is desirable for a photochromic article having a protective layer. First, cracks should be less likely to occur in the protective layer. This is because cracks in the protective layer can cause clouding and / or optical defects in the photochromic article. Second, even if scratches occur in the photochromic article, the scratches should be less visible. This is because the presence of easily visible scratches on the photochromic article reduces the appearance quality of the photochromic article. Third, the provision of a protective layer should result in minimal deterioration in the optical and photochromic performance of the photochromic article.

[0005] In view of the above, one aspect of the present invention aims to provide a photochromic article that has a protective layer that is less susceptible to cracking, in which scratches are less visible, and in which the provision of the protective layer results in little deterioration in optical performance and photochromic performance.

[0006] One aspect of the present invention is as follows. [1] A curable composition for forming a protective layer of a photochromic article (hereinafter also simply referred to as "composition") that satisfies the following (1) to (3): (1) The composition contains a polyfunctional (meth)acrylate having an oxyalkylene structure. (2) The content of the oxyalkylene structure in the solid content of the composition is 20% by mass or more and 65% by mass or less. (3) The concentration of (meth)acryloyl groups in the solid content of the composition is 4.0 mmol / g or more and 8.0 mmol / g or less. [2] A photochromic article having a photochromic layer containing a photochromic compound, and a protective layer that is a cured layer obtained by curing the composition described in [1]. [3] The photochromic article described in [2], wherein the protective layer has an indentation modulus of 1.0 GPa or more and 5.0 GPa or less as measured by a nanoindentation method. [4] The photochromic article described in [2] or [3], wherein the protective layer has a thickness of 1 μm or more and 50 μm or less. [5] The photochromic article according to any one of [2] to [4], further comprising a substrate. [6] The photochromic article according to [5], comprising the substrate, the photochromic layer, the protective layer, and an organosilicon-based cured layer, in this order. [7] The photochromic article according to any one of [2] to [6], wherein the polyfunctional (meth)acrylate having an oxyalkylene structure is at least one selected from the group consisting of polyfunctional (meth)acrylates represented by the following formula 1 and polyfunctional (meth)acrylates represented by the following formula 2: (In Formula 1, X represents an oxyalkylene structure, and multiple Xs present in the molecule are the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule are the same or different. a to f each independently represent 1 or more, and the sum of a to f is the total number of oxyalkylene structures in the molecule.) (In Formula 2, R represents an oxyalkylene structure, and multiple R present in the molecule are the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Z present in the molecule are the same or different. 1 to n are each independently 1 or greater, and the sum of 1 to n is the total number of oxyalkylene structures in the molecule.) [8] The photochromic article according to [2], wherein the protective layer has an indentation modulus of 1.0 GPa or more and 5.0 GPa or less as measured by a nanoindentation method, the protective layer has a thickness of 1 μm or more and 50 μm or less, and the photochromic article has a substrate, the photochromic layer, the protective layer, and an organosilicon-based cured layer, in this order, and the polyfunctional (meth)acrylate having an oxyalkylene structure is one or more selected from the group consisting of polyfunctional (meth)acrylates represented by Formula 1 above and polyfunctional (meth)acrylates represented by Formula 2 above. [9] The photochromic article according to any of [2] to [8], which is a spectacle lens.

[10] The photochromic article according to any one of [2] to [8], which is a lens for goggles, a visor part of a sun visor, or a shielding material for a helmet.

[11] Eyeglasses equipped with the eyeglass lens according to [9].

[0007] According to one aspect of the present invention, it is possible to provide a photochromic article that has a protective layer that is resistant to cracking, in which scratches are less visible, and in which the provision of the protective layer causes little deterioration in optical performance and photochromic performance.

[0008] [Curable Composition for Forming Protective Layer of Photochromic Article] The composition will now be described in more detail.

[0009] The composition is a curable composition for forming a protective layer of a photochromic article. In the present invention and this specification, a "photochromic article" refers to an article containing a photochromic compound. In a photochromic article, the photochromic compound is contained in, for example, a layer (photochromic layer) provided on a substrate. The photochromic layer will be described in detail later. A protective layer formed from the composition can be provided, for example, on the photochromic layer, which can contribute to improving the durability of the photochromic article.

[0010] The above composition is a curable composition. In the present invention and this specification, a "curable composition" refers to a composition containing one or more polymerizable compounds, and a "polymerizable compound" refers to a compound having one or more polymerizable groups in one molecule. A "(meth)acrylate" is a polymerizable compound. In the present invention and this specification, the term "(meth)acrylate" is used to encompass both acrylate and methacrylate. An "acrylate" is a compound having one or more acryloyl groups in one molecule. A "methacrylate" is a compound having one or more methacryloyl groups in one molecule. The functionality of a (meth)acrylate is the number of groups selected from the group consisting of acryloyl groups and methacryloyl groups contained in one molecule. In the present invention and this specification, a "methacrylate" refers to a compound containing only methacryloyl groups as (meth)acryloyl groups, and a compound containing both acryloyl and methacryloyl groups as (meth)acryloyl groups is called an acrylate. The acryloyl group may be contained in the form of an acryloyloxy group, and the methacryloyl group may be contained in the form of a methacryloyloxy group. In the present invention and this specification, the term "(meth)acryloyl group" is used to encompass both acryloyl and methacryloyl groups, and the term "(meth)acryloyloxy group" is used to encompass both acryloyloxy and methacryloyloxy groups. Furthermore, unless otherwise specified, the groups described may be substituted or unsubstituted. When a group has a substituent, examples of the substituent include an alkyl group (e.g., an alkyl group having 1 to 6 carbon atoms), a hydroxy group, an alkoxy group (e.g., an alkoxy group having 1 to 6 carbon atoms), a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom), a cyano group, an amino group, a nitro group, an acyl group, and a carboxyl group. The "number of carbon atoms" in a substituted group refers to the number of carbon atoms in the portion excluding the substituent.

[0011] <Polyfunctional (meth)acrylate having an oxyalkylene structure> The composition contains a polyfunctional (meth)acrylate having an oxyalkylene structure. That is, the composition satisfies the above (1). In the present invention and this specification, the term "oxyalkylene structure" refers to a "-R １ -O-" where R １ represents an alkylene group. １ The alkylene group represented by the formula (I) can be, for example, an alkylene group having 2 or more carbon atoms. The number of carbon atoms in the alkylene group can be, for example, 6 or less, 5 or less, 4 or less, or 3 or less. When the polyfunctional (meth)acrylate having an oxyalkylene structure has two or more oxyalkylene structures in the molecule, the alkylene groups in those oxyalkylene structures are the same or different alkylene groups. In one embodiment, the polyfunctional (meth)acrylate having an oxyalkylene structure can have one oxyalkylene structure or a structure in which two or more oxyalkylene structures are consecutive, at only one position in the molecule. When a structure in which two or more oxyalkylene structures are consecutive is called a polyoxyalkylene structure, the polyoxyalkylene structure can be formed by adding "-(R １ -O) ｎ１ -" and R １ is the same as above, and n1 is the number of repeating units, and can be, for example, 2 or more and 15 or less. In another embodiment, the polyfunctional (meth)acrylate having an oxyalkylene structure can have one oxyalkylene structure or a structure having two or more consecutive oxyalkylene structures (a polyoxyalkylene structure) at two or more positions within the molecule. In this case, the total number of oxyalkylene structures at the multiple positions can be, for example, 2 or more and 15 or less.

[0012] The functionality of the polyfunctional (meth)acrylate having an oxyalkylene structure is 2 or more, and can be, for example, from 2 to 6. As described above, the functionality of the (meth)acrylate refers to the number of groups selected from the group consisting of acryloyl groups and methacryloyl groups contained in one molecule.

[0013] Specific examples of polyfunctional (meth)acrylates having an oxyalkylene structure include pentafunctional or hexafunctional (meth)acrylates represented by the following formula 1. In formula 1, X represents "-R １ X represents an oxyalkylene structure (—O—), and multiple Xs present in the molecule are the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule are the same or different. a to f each independently represent 1 or more, and the sum of a to f represents the total number of oxyalkylene structures in the molecule, which can be, for example, 6 to 15.

[0014]

[0015] A specific example of the polyfunctional (meth)acrylate having an oxyalkylene structure is a trifunctional (meth)acrylate represented by the following formula 2. In formula 2, R represents "-R １ -O-" (oxyalkylene structure), and multiple R's present in the molecule are the same or different oxyalkylene structures. Z's represent a hydrogen atom or a methyl group, and multiple Z's present in the molecule are the same or different. 1 to n's are each independently 1 or more, and the sum of 1 to n's is the total number of oxyalkylene structures in the molecule, which can be, for example, 3 or more and 15 or less.

[0016]

[0017] However, in the present invention, the polyfunctional (meth)acrylate having an oxyalkylene structure is not limited to the above examples.

[0018] The content of the oxyalkylene structure in the solid content of the composition is 20% by mass or more and 65% by mass or less. That is, the composition satisfies the above (2). The composition has a (meth)acryloyl group concentration in the solid content of the composition of 4.0 mmol / g or more and 8.0 mmol / g or less and contains a polyfunctional (meth)acrylate having an oxyalkylene structure, which can contribute to both suppressing cracking in the protective layer formed from the composition and making scratches on the photochromic article less visible. Furthermore, the content of the oxyalkylene structure in the solid content of the composition of 20% by mass or more can contribute to suppressing cracking in the protective layer. From the viewpoint of further suppressing cracking, the content of the oxyalkylene structure in the solid content of the composition is preferably 22% by mass or more, with 23% by mass or more and 24% by mass or more being more preferred in that order. The content of the oxyalkylene structure in the solid content of the composition of 65% by mass or less can contribute to suppressing deterioration of optical performance due to the provision of a protective layer. This is because it is presumed that if the content of the oxyalkylene structure in the curable composition for forming a protective layer is excessively high, part of the composition may be mixed into other layers, such as the photochromic layer, during the production of the photochromic article, which may cause a deterioration in the optical performance of the photochromic article. From the above viewpoint, the content of the oxyalkylene structure in the solid content of the composition is preferably 63% by mass or less, more preferably 60% by mass or less, and more preferably 58% by mass or less. The content of the oxyalkylene structure in the solid content of the composition can be controlled by the type of polyfunctional (meth)acrylate having an oxyalkylene structure contained in the composition and the content of the polyfunctional (meth)acrylate having an oxyalkylene structure in the composition. The content of the polyfunctional (meth)acrylate having an oxyalkylene structure in the composition can be, for example, 100% by mass or less, less than 100% by mass, 99% by mass or less, 95% by mass or less, 90% by mass or less, 85% by mass or less, 80% by mass or less, 75% by mass or less, 70% by mass or less, or 65% by mass or less, where the total amount of the polymerizable compounds contained in the composition is 100% by mass.Furthermore, the content of the polyfunctional (meth)acrylate having an oxyalkylene structure in the composition can be, for example, 50% by mass or more, 55% by mass or more, or 60% by mass or more, where the total amount of the polymerizable compounds contained in the composition is 100% by mass.

[0019] In the present invention and this specification, the solid content of the composition refers to all components excluding the solvent in a solvent-containing composition. In a solvent-free composition, the solid content refers to all components of the composition. The composition may or may not contain a solvent. When a solvent is contained, any solvent can be used in any amount as long as it does not inhibit the progress of the polymerization reaction of the curable composition.

[0020] The (meth)acryloyl group concentration in the solid content of the composition is 4.0 mmol / g or more and 8.0 mmol / g or less. That is, the composition satisfies the above (3). A (meth)acryloyl group concentration of 8.0 mmol / g or less in the solid content of the composition can contribute to suppressing cracking in the protective layer and suppressing deterioration of the photochromic performance of the photochromic article. Regarding the deterioration of the photochromic performance of the photochromic article, it is presumed that if the (meth)acryloyl group concentration of the curable composition for forming a protective layer is excessively high, part of such composition may be mixed into a part containing a photochromic compound (e.g., a photochromic layer) during the production of the photochromic article, which may inhibit the expression of the photochromic performance of the photochromic compound. In order to further suppress the occurrence of cracks in the protective layer and to further suppress the deterioration of the photochromic performance of the photochromic article, the (meth)acryloyl group concentration in the solid content of the composition is preferably 7.8 mmol / g or less, and more preferably 7.6 mmol / g or less, 7.4 mmol / g or less, 7.2 mmol / g or less, and 7.0 mmol / g or less in that order. A (meth)acryloyl group concentration in the solid content of the composition of 4.0 mmol / g or more can contribute to making scratches on the photochromic article less visible. This is presumably because deep scratches are less likely to occur in photochromic articles having a protective layer formed from a composition having a (meth)acryloyl group concentration in the solid content of 4.0 mmol / g or more. In order to make scratches in the photochromic article even less visible, the (meth)acryloyl group concentration in the solid content of the composition is preferably 4.2 mmol / g or more, and more preferably 4.4 mmol / g or more, 4.6 mmol / g or more, 4.8 mmol / g or more, 5.0 mmol / g or more, 5.2 mmol / g or more, and 5.4 mmol / g or more in that order.

[0021] The (meth)acryloyl group concentration in the solid content of the composition can be controlled by the (meth)acrylate content in the composition. In one embodiment, the composition contains only a polyfunctional (meth)acrylate having an oxyalkylene structure as the (meth)acrylate. In this case, the composition can contain one or more polyfunctional (meth)acrylates having an oxyalkylene structure. In another embodiment, the composition contains, as the (meth)acrylate, one or more polyfunctional (meth)acrylates having an oxyalkylene structure and one or more (meth)acrylates not having an oxyalkylene structure. In this case, the (meth)acrylate not having an oxyalkylene structure is not particularly limited, and one or more monofunctional (meth)acrylates and polyfunctional (meth)acrylates having known structures can be used. Specific examples include, but are not limited to, (meth)acrylates in which a to f are zero in Formula 1 shown above and (meth)acrylates in which l to n are zero in Formula 2 shown above. The content of the polyfunctional (meth)acrylate having an oxyalkylene structure in the composition may be, for example, 100% by mass or less, less than 100% by mass, 99% by mass or less, 95% by mass or less, 90% by mass or less, 85% by mass or less, 80% by mass or less, 75% by mass or less, 70% by mass or less, or 65% by mass or less, where the total amount of (meth)acrylate contained in the composition is 100% by mass. The content of the polyfunctional (meth)acrylate having an oxyalkylene structure in the composition may be, for example, 50% by mass or more, 55% by mass or more, or 60% by mass or more, where the total amount of (meth)acrylate contained in the composition is 100% by mass.

[0022] <Other Components> The composition contains a polyfunctional (meth)acrylate having an oxyalkylene structure as an essential component. An example of an optional component is the above-described (meth)acrylate not having an oxyalkylene structure. The composition may contain, for example, 80% by mass or more, 85% by mass or more, 90% by mass or more, or 95% by mass or more of the (meth)acrylate, where the total amount of the polymerizable compounds is 100% by mass, and the total amount of the polymerizable compounds may be (meth)acrylate.

[0023] The composition may contain one or more of the various additives that can be contained in a curable composition at any content. Examples of such additives include various known additives such as a polymerization initiator for promoting a polymerization reaction and a leveling agent for improving the coating suitability of the composition. The additives may be used in any amount.

[0024] For example, as the polymerization initiator, a known polymerization initiator capable of functioning as a polymerization initiator for (meth)acrylate can be used, a radical polymerization initiator is preferred, and it is more preferred that the polymerization initiator contains only a radical polymerization initiator. Further, as the polymerization initiator, a photopolymerization initiator or a thermal polymerization initiator can be used, and a photopolymerization initiator is preferred from the viewpoint of progressing the polymerization reaction in a short time. Examples of the photoradical polymerization initiator include benzoin ketals such as 2,2-dimethoxy-1,2-diphenylethan-1-one; α-hydroxyketones such as 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one; α-aminoketones such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one and 1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one; oxime esters such as 1-[(4-phenylthio)phenyl]-1,2-octadione-2-(benzoyl)oxime; bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxy ...hydroxybenzoyl)phenylphosphine oxide, bis(2,6-dihydroxybenzoyl)phenylpho 2,4,5-triarylimidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; benzophenone compounds such as benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, and 4-methoxy-4'-dimethylaminobenzophenone;quinone compounds such as 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, and 2,3-dimethylanthraquinone; benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin compounds such as benzoin, methylbenzoin, and ethylbenzoin; benzyl compounds such as benzyl dimethyl ketal; acridine compounds such as 9-phenylacridine and 1,7-bis(9,9'-acridinylheptane); N-phenylglycine, coumarin, and the like. In addition, in the 2,4,5-triarylimidazole dimer, the substituents on the aryl groups of the two triarylimidazole moieties may be the same to give a symmetrical compound, or may be different to give an asymmetrical compound. Furthermore, a thioxanthone compound may be combined with a tertiary amine, such as the combination of diethylthioxanthone and dimethylaminobenzoic acid. Among these, α-hydroxyketone and phosphine oxide are preferred from the viewpoints of curability, transparency, and heat resistance. The content of the polymerization initiator may be, for example, in the range of 0.1 to 5.0% by mass, with the total amount of polymerizable compounds contained in the composition being 100% by mass.

[0025] In one embodiment, the composition may also include an ultraviolet absorber. Examples of the ultraviolet absorber include hydroxyphenyl triazine compounds such as 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-s-triazine, 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-s-triazine, 2-[2-hydroxy-4-(2-ethylhexyloxy)phenyl]-4,6-diviphenyl-s-triazine, and 2-[[2-hydroxy-4-[1-(2-ethylhexyloxycarbonyl)ethyloxy]phenyl]]-4,6-diphenyl-s-triazine, 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol and 2-(5-chloro-2-benzotriazolyl)-6-tert-butyl-p-cresol. One or more of various ultraviolet absorbers can be used, such as benzotriazole-based ultraviolet absorbers. The inclusion of an ultraviolet absorber in the composition can contribute to improving the weather resistance of a photochromic article having a protective layer formed from this composition. When the composition contains an ultraviolet absorber, the content of the ultraviolet absorber can be, for example, in the range of 0.1 to 1.0 mass %, where the total amount of the polymerizable compounds contained in the composition is 100 mass %.

[0026] The composition can be prepared by mixing the various components described above simultaneously or sequentially in any order.

[0027] [Photochromic Article] One aspect of the present invention relates to a photochromic article having a photochromic layer containing a photochromic compound and a protective layer that is a cured layer obtained by curing the composition. The photochromic article will be described in more detail below.

[0028] <Photochromic Layer> (Photochromic Compound) As the photochromic compound, known compounds exhibiting photochromic properties can be used. The photochromic compound can exhibit photochromic properties, for example, when exposed to ultraviolet light. Examples of the photochromic compound include compounds having known photochromic skeletons, such as fulgimide compounds, spirooxazine compounds, chromene compounds, and indeno-fused naphthopyran compounds. Specific examples of the indeno-fused naphthopyran compound include indeno-fused naphthopyran compounds having various substituents, such as electron-withdrawing substituents, as described in EP 2078006 B1, US 2006 / 0226402 A1, and U.S. Pat. No. 6,296,785. Furthermore, examples of the photochromic compound include at least one selected from the group consisting of photochromic compounds represented by general formula A, photochromic compounds represented by general formula B, and photochromic compounds represented by general formula C, as described in WO 2022 / 138966. The photochromic compound may be used alone or in combination of two or more. The content of the photochromic compound in the composition may be, for example, about 0.1 to 15% by mass, with the mass of the photochromic layer being 100% by mass, but is not limited to this range.

[0029] (Components for forming photochromic layer) The photochromic layer can be a cured layer obtained by curing a curable composition containing one or more photochromic compounds. Various components, such as polymerizable compounds, contained in the curable composition for forming the photochromic layer can be applied to known techniques related to photochromic articles. From the viewpoint of adhesion to the protective layer, the photochromic layer is preferably a cured layer obtained by curing a curable composition containing (meth)acrylate as the polymerizable compound.

[0030] In one embodiment, the photochromic layer can be a cured layer formed by applying a curable composition containing one or more photochromic compounds directly to the surface of a substrate or by applying the composition to the surface of a layer provided on the substrate and then curing the resulting coating. Known coating methods, such as spin coating and dip coating, can be used as the coating method, with spin coating being preferred from the viewpoint of coating uniformity. The polymerization treatment can be light irradiation and / or heat treatment, with light irradiation being preferred from the viewpoint of progressing the polymerization reaction in a short period of time. The polymerization conditions can be determined depending on the types and compositions of the various components contained in the curable composition. The above descriptions regarding the coating method and polymerization treatment also apply to the curable composition for forming a protective layer. The thickness of the photochromic layer is preferably in the range of 1 to 50 μm, more preferably in the range of 5 to 50 μm, and even more preferably in the range of 20 to 50 μm.

[0031] <Protective Layer> The photochromic article has a protective layer, which is a cured layer obtained by curing the curable composition for forming a protective layer. The protective layer can be provided directly on the surface of the photochromic layer, or on the surface of a layer located above the photochromic layer. Examples of layers that can be located between the photochromic layer and the protective layer include a primer layer. The thickness of the protective layer is preferably 10 μm or more, and more preferably 15 μm or more. The thickness of the protective layer is preferably 50 μm or less, and is more preferably 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, and 20 μm or less in this order. The protective layer can contribute to improving the durability of the photochromic article. It can also protect the photochromic layer and prevent scratches from occurring on the photochromic layer until further processing (e.g., the formation of the cured layer described below) is performed.

[0032] The composition allows the formation of a protective layer having appropriate hardness and flexibility. This can contribute to suppressing cracking in the protective layer and making scratches on the photochromic article less visible. Examples of indicators of hardness and flexibility include the indentation modulus measured by nanoindentation. It is preferable that the indentation modulus measured by nanoindentation of a protective layer formed from a curable composition containing a polyfunctional (meth)acrylate having an oxyalkylene structure is 1.0 GPa or more in order to make scratches on the photochromic article less visible. From this perspective, the indentation modulus is more preferably 1.5 GPa or more, with 2.0 GPa or more, 2.5 GPa or more, 3.0 GPa or more, and 3.5 GPa or more being more preferred in this order. On the other hand, it is preferable that the indentation modulus measured by nanoindentation of a protective layer formed from a curable composition containing a polyfunctional (meth)acrylate having an oxyalkylene structure is 5.0 GPa or less in order to suppress cracking in the protective layer. From this point of view, the indentation elastic modulus is more preferably 4.8 GPa or less, and even more preferably 4.6 GPa or less.

[0033] The indentation modulus of the protective layer according to the present invention and this specification by the nanoindentation method is the composite modulus of elasticity Er, which is determined by measuring the surface of the protective layer by the following method in a measurement environment with an ambient temperature of 30°C and a relative humidity of 50%. When the photochromic article has one or more layers on the protective layer, the layer on the protective layer is removed by a known method to expose the surface of the protective layer, and measurement can be performed on the exposed surface of the protective layer by the following method. A load-unload test is performed by the nanoindentation method. The measurement conditions are as follows. As a measuring device, for example, an ultra-microindentation hardness tester ENT-2100 manufactured by Elionix can be used. Indenter: Berkovich (triangular pyramid), edge angle: 115° Measurement mode: single indentation measurement Indentation depth: 1.0 μm Holding time when maximum load is reached: 1 second The composite elastic modulus Er is calculated using the following formula from the slope of the tangent at maximum load of the unloading curve of the load-displacement curve obtained by the load-unloading test (contact stiffness S) and the contact area between the indenter and the sample at that time (contact projected area Ac).

[0034]

[0035] <Substrate> In one embodiment, the photochromic article can be an optical article. Optical articles include various articles such as eyeglass lenses, goggle lenses, sun visor visor portions, and helmet shield members. For example, the photochromic article can have a photochromic layer and a protective layer on a substrate selected depending on the type of optical article. As an example of the substrate, the eyeglass lens substrate can be a plastic lens substrate or a glass lens substrate. The glass lens substrate can be, for example, a lens substrate made of inorganic glass. As the lens substrate, a plastic lens substrate is preferred from the viewpoints of being lightweight, less likely to break, and easy to handle. Examples of plastic lens substrates include (meth)acrylic resins, styrene resins, polycarbonate resins, allyl resins, allyl carbonate resins such as diethylene glycol bisallyl carbonate resin (CR-39), vinyl resins, polyester resins, polyether resins, urethane resins obtained by reacting an isocyanate compound with a hydroxy compound such as diethylene glycol, thiourethane resins obtained by reacting an isocyanate compound with a polythiol compound, and cured products (commonly referred to as transparent resins) obtained by curing a curable composition containing a (thio)epoxy compound having one or more disulfide bonds in the molecule. Lens substrates may be undyed (colorless lenses) or dyed (dyed lenses). The refractive index of the lens substrate may be, for example, approximately 1.50 to 1.76. However, the refractive index of the lens substrate is not limited to the above range and may be within the above range or may deviate above or below the range. In the present invention and this specification, the refractive index refers to the refractive index for light with a wavelength of 500 nm. The lens substrate may be a lens having refractive power (a so-called prescription lens) or a lens without refractive power (a so-called non-prescription lens).

[0036] The spectacle lens can be any of various lenses, such as a single-vision lens, a multifocal lens, or a progressive-power lens. The type of lens is determined by the surface shapes of both sides of the lens substrate. The surface of the lens substrate may be convex, concave, or flat. In ordinary lens substrates and spectacle lenses, the object-side surface is convex and the eyeball-side surface is concave. However, the present invention is not limited to this. The photochromic layer can usually be provided on the object-side surface of the lens substrate, but it may also be provided on the eyeball-side surface.

[0037] The photochromic layer may be provided directly on the surface of the substrate, or may be provided indirectly via one or more other layers. Examples of such other layers include a primer layer for improving adhesion between the photochromic layer and the substrate. Such primer layers are well known. The thickness of the primer layer may be, for example, 0.1 to 20 μm.

[0038] <Optional Layers> The photochromic article can have a layer structure of "substrate / photochromic layer / protective layer." With regard to the layer structure, " / " is used to mean both a structure in which the layers are in direct contact without any other layer interposed therebetween and a structure in which the layers are provided via one or more other layers. For example, as described above, a primer layer may be present between the substrate and the photochromic layer, but the substrate and the photochromic layer may also be in direct contact with each other. In one embodiment, the photochromic article can have a layer structure of "substrate / photochromic layer / protective layer / other cured layer." In such a layer structure, the other cured layer may be a cured layer generally referred to as a hard coat layer. By providing a hard coat layer in addition to the protective layer, the durability of the photochromic article can be further improved. In one embodiment, the impact resistance of the photochromic article can also be improved by providing a hard coat layer. In one embodiment, the other cured layer can be in direct contact with the protective layer without any other layer interposed therebetween.

[0039] The thickness of the other cured layer can be, for example, in the range of 0.1 to 10 μm, preferably in the range of 1 to 10 μm, more preferably in the range of 1 to 8 μm, and even more preferably in the range of 1 to 5 μm. In one embodiment, the other cured layer can be thinner than the protective layer. An example of the other cured layer is an organosilicon-based cured layer. Organosilicon-based cured layers are generally preferred because they have excellent impact resistance. Furthermore, when an anti-reflection film is further provided, for example, an organosilicon-based cured layer is generally preferred because it has excellent adhesion to the anti-reflection film.

[0040] The organosilicon-based cured layer is a cured layer obtained by curing a curable composition containing an organosilicon compound. Examples of the organosilicon compound include organosilicon compounds capable of generating silanol groups upon polymerization, and organopolysiloxanes having reactive groups such as halogen atoms or amino groups that undergo condensation reactions with silanol groups. Examples of the organosilicon compound include silane coupling agents having polymerizable groups such as vinyl groups, allyl groups, (meth)acryloyl groups, and (meth)acryloyloxy groups, and hydrolyzable groups such as alkoxy groups. The curable composition containing the organosilicon compound may contain particles of inorganic substances such as silicon oxides and titanium oxides to adjust the refractive index, etc. For details of the curable composition containing the organosilicon compound, known techniques related to organosilicon-based cured layers that can function as hard coat layers can be applied. Such curable compositions can be cured by irradiating light and / or heating, depending on the types of components contained in the composition, to promote polymerization.

[0041] The photochromic article may further include one or more layers in addition to the various layers described above. Examples of such layers include layers known as functional layers for optical articles, such as an anti-reflection layer, a water-repellent or hydrophilic anti-fouling layer, and an anti-fogging layer.

[0042] One example of the photochromic article is a spectacle lens. Other examples of the photochromic article include a goggle lens, a sun visor, and a helmet shield. The photochromic article can be suitably used as an optical article having an anti-glare function.

[0043] [Eyeglasses] One aspect of the present invention relates to eyeglasses equipped with the above-described photochromic article, which is an eyeglass lens. Details of the eyeglass lenses included in the eyeglasses are as described above. By including such eyeglass lenses, the eyeglasses can, for example, exhibit an anti-glare effect like sunglasses outdoors by the photochromic compound included in the photochromic layer changing color when irradiated with sunlight, and when returning indoors, the photochromic compound fades, thereby restoring transparency. Known technologies can be applied to the construction of the frames and other components of the eyeglasses.

[0044] The present invention will be further described below with reference to examples. However, the present invention is not limited to the embodiments shown in the examples. The steps and evaluations described below were carried out in the atmosphere at room temperature (20°C ± 5°C) unless otherwise specified.

[0045] Example 1 Preparation of Spectacle Lens (Photochromic Article) A plastic lens substrate (manufactured by HOYA Corporation under the trade name EYAS: center thickness 2.5 mm, radius 75 mm, S-4.00) was immersed in a 10% by mass aqueous solution of sodium hydroxide (liquid temperature 60°C) for 5 minutes, then washed with pure water and dried. A primer layer was then formed on the convex surface (object-side surface) of this plastic lens substrate. Specifically, an aqueous polyurethane resin liquid (polycarbonate polyol-based polyurethane emulsion; viscosity 100 CPS, solids concentration 38% by mass) was applied to the convex surface of the plastic lens substrate by spin coating in an environment of 25°C and 50% relative humidity, followed by natural drying for 15 minutes to form a 10 μm-thick primer layer. A photochromic layer-forming polymerizable composition prepared as follows was applied to the primer layer by spin coating to form a coating layer. The surface of this coating layer was irradiated with ultraviolet light (wavelength 405 nm) in a nitrogen atmosphere (oxygen concentration 500 ppm or less), and the coating layer was cured to form a photochromic layer. The thickness of the formed photochromic layer was 25 μm. A polymerizable composition for forming a protective layer, prepared as follows, was applied onto the photochromic layer by spin coating to form a coating layer. The surface of this coating layer was irradiated with ultraviolet light (wavelength 405 nm) in a nitrogen atmosphere (oxygen concentration 500 ppm or less), and the coating layer was cured to form a protective layer. The thickness of the formed protective layer was 15 μm.

[0046] <Preparation of Polymerizable Composition for Forming Photochromic Layer> A curable composition consisting of 20 parts by mass of trimethylolpropane trimethacrylate, 35 parts by mass of BPE oligomer (2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane), 10 parts by mass of EB6A (polyester oligomer hexaacrylate), 10 parts by mass of polyethylene glycol diacrylate having an average molecular weight of 532, and 10 parts by mass of glycidyl methacrylate was prepared in a plastic container. To 100 parts by mass of the above curable composition, the following photochromic compound (an indeno-fused naphthopyran compound represented by the structural formula described in U.S. Pat. No. 6,296,785), a photoradical polymerization initiator (bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (Omnirad 819 manufactured by IGM Resin B.V.)), an antioxidant (bis[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid][ethylenebis(oxyethylene)]), and a light stabilizer (bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate) were mixed and thoroughly stirred. The mixture was then degassed using a rotation-revolution type stirring and degassing apparatus. In this way, a curable composition for forming a photochromic layer was prepared.

[0047]

[0048] <Preparation of Polymerizable Composition for Forming Protective Layer> In a plastic container, NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd., as a polyfunctional (meth)acrylate having an oxyalkylene structure, was mixed with a polymerization initiator (Omnirad 819 manufactured by IGM Resins B.V.) and a leveling agent (DOWSIL L-7001 manufactured by Dow-Toray Industries, Inc.), thoroughly stirred, and then degassed using a rotation-revolution type stirring / defoaming apparatus. In this way, the curable composition for forming a protective layer of Example 1 was prepared. In the curable composition for forming a protective layer of Example 1, the total amount (100% by mass) of the polymerizable compound contained in the composition was NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. is an ethoxylated dipentaerythritol polyacrylate represented by formula 1, in which X is ethylene oxide (having an ethylene group as the alkylene group), Z is a hydrogen atom, and the total of a to f is approximately 12. With the total amount of polymerizable compounds taken as 100% by mass, the amount of polymerization initiator used was 1% by mass, and the amount of leveling agent used was 0.3% by mass.

[0049] Using the eyeglass lenses on which the protective layer was formed by the above method, the evaluations (1) to (5) described below were carried out.

[0050] A hard coat layer was further formed on the eyeglass lens on which the protective layer was formed by the above method by the following method. The eyeglass lens on which the hard coat layer was formed in this way was used to carry out the evaluation (6) described below.

[0051] <Formation of Hard Coat Layer> 17 parts by mass of γ-glycidoxypropyltrimethoxysilane, 30 parts by mass of methanol, and 28 parts by mass of water-dispersed colloidal silica (solid content 40% by mass, average particle size 15 nm) were added to a glass container equipped with a magnetic stirrer, thoroughly mixed, and stirred at 5°C for 24 hours. Next, 15 parts by mass of propylene glycol monomethyl ether, 0.05 parts by mass of a silicone surfactant, and 1.5 parts by mass of aluminum acetylacetonate as a curing agent were added, thoroughly stirred, and then filtered to prepare a hard coating liquid (polymerizable composition for forming a hard coat layer). The hard coating liquid was coated on the surface of the protective layer of the eyeglass lens prepared above by dip coating (pull-up speed 20 cm / min). The mixture was then heated and cured for 60 minutes in a heat treatment furnace at a furnace temperature of 100°C, forming a 3 μm-thick hard coat layer (organosilicon-based cured layer).

[0052] [Evaluation Method] (1) Indentation Elastic Modulus Er of Protective Layer (Nanoindentation Measurement) The indentation elastic modulus Er of the protective layer was determined by the nanoindentation method described above. The measuring device used was an ultra-microindentation hardness tester ENT-2100 manufactured by Elionix.

[0053] (2) Crack Evaluation The eyeglass lenses having the protective layer were annealed for 2 hours in an annealing furnace at an internal temperature of 90°C. The eyeglass lenses were removed from the annealing furnace and visually observed to evaluate the presence or absence of cracks in the protective layer. The evaluation results were rated as "x" when cracks were observed and "o" when no cracks were observed.

[0054] (3) Optical Performance (Luminous Transmittance) A spectacle lens produced by the method described in Example 1 except that no protective layer was formed was used as a "reference lens." The luminous transmittance was determined for each of the spectacle lens of Example 1 and the reference lens in accordance with JIS T 7333:2005. The luminous transmittance of the spectacle lens of Example 1 was designated Tc, the luminous transmittance of the reference lens was designated Td, and the difference Δ in luminous transmittance between the spectacle lens of Example 1 and the reference lens was calculated as Δ=Tc-Td.

[0055] (4) Photochromic Performance (Difference in Fading Rate from Reference Lens, ΔSfading) The fading rate was determined for each of the spectacle lens of Example 1 and the reference lens by the following method. The fading rate of the spectacle lens of Example 1 was defined as Sfading(c), the fading rate of the reference lens was defined as Sfading(d), and the difference in fading rate from the reference lens, ΔSfading, was calculated as ΔSfading=Sfading(c)-Sfading(d).

[0056] <Fade Rate> The convex surface of each eyeglass lens was irradiated with light using a xenon lamp through an aeromass filter for 15 minutes (900 seconds) to color the photochromic compound in the photochromic layer. The transmittance (measurement wavelength: 550 nm) during this coloring process was measured using a spectrophotometer manufactured by Otsuka Electronics Co., Ltd. The light irradiation was performed so that the irradiance and irradiance tolerances were as shown in Table 1 below, as specified in JIS T7333:2005. The transmittance measured in this manner is referred to as the "transmittance during coloring." After measuring the transmittance during coloring, the transmittance was measured 60 seconds after the light irradiation was stopped (hereinafter referred to as the "60-second transmittance during color fading"). The fade rate (unit: % / sec) was calculated using the formula: Fade Rate = [(60-second transmittance during color fading - transmittance during color fading) / 60]. The higher the value of the fade rate thus determined, the faster the fade rate.

[0057]

[0058] (5) Photochromic Performance (difference in time to reach 70% luminous transmittance with reference lens, Δt70%) The time to reach 70% transmittance was determined for each of the spectacle lens of Example 1 and the reference lens by the following method. The time to reach 70% transmittance of the spectacle lens of Example 1 was defined as t70%(c), and the time to reach 70% transmittance of the reference lens was defined as t70%(d), and the difference in time to reach 70% transmittance with the reference lens, Δt70%, was calculated as Δt70%=t70%(c)-t70%(d).

[0059] <Time to reach 70% transmittance> After the light irradiation for measuring the transmittance in the colored state was stopped, the initial transmittance was set to 100%, and the time required for the lens transmittance to recover to 70% (the lens faded) was determined. The time thus determined is referred to as the "time to reach 70% transmittance." It can be said that the shorter the value of the time to reach 70% transmittance determined in this manner, the faster the fade rate.

[0060] (6) Scratch Visibility A scratch test was performed on the surface of the hard coat layer by sliding a metal indenter with a diameter of 0.7 mm on the surface of the hard coat layer at a speed of 25 mm / min while applying a load of 750 g. The spectacle lens surface (hard coat layer surface) after the scratch test was visually observed, and the degree of visibility of scratches (scratch marks) was evaluated on a three-point scale of A to C. An evaluation result of "A" indicated that no scratches were visible, an evaluation result of "B" indicated that scratches were slightly visible, and an evaluation result of "C" indicated that scratches were clearly visible.

[0061] Example 2 Spectacle lenses were produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, 80 mass % of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. and 20 mass % of NK Ester A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd. were used relative to the total amount (100 mass %) of the polymerizable compounds contained in the composition.

[0062] Example 3 Spectacle lenses were produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, 60 mass % of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. and 40 mass % of NK Ester A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd. were used relative to the total amount (100 mass %) of the polymerizable compounds contained in the composition.

[0063] Example 4 Spectacle lenses were produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, NK Ester A-TMPT-3EO manufactured by Shin-Nakamura Chemical Co., Ltd. was used instead of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. NK Ester A-TMPT-3EO manufactured by Shin-Nakamura Chemical Co., Ltd. is ethoxylated trimethylolpropane triacrylate represented by formula 2, in which R is ethylene oxide (having an ethylene group as the alkylene group), Z is a hydrogen atom, and the sum of l to n is approximately 3.

[0064] Example 5 Spectacle lenses were produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, NK Ester A-TMPT-9EO manufactured by Shin-Nakamura Chemical Co., Ltd. was used instead of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. NK Ester A-TMPT-9EO manufactured by Shin-Nakamura Chemical Co., Ltd. is ethoxylated trimethylolpropane triacrylate represented by formula 2, in which R is ethylene oxide (having an ethylene group as the alkylene group), Z is a hydrogen atom, and the sum of l to n is approximately 9.

[0065] Comparative Example 1 A spectacle lens was produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, 30 mass % of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. and 70 mass % of NK Ester A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd. were used relative to the total amount (100 mass %) of the polymerizable compounds contained in the composition.

[0066] Comparative Example 2 Spectacle lenses were produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, NK Ester AT-20E manufactured by Shin-Nakamura Chemical Co., Ltd. was used instead of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. NK Ester AT-20E manufactured by Shin-Nakamura Chemical Co., Ltd. is an ethoxylated trimethylolpropane triacrylate represented by formula 2, in which R is ethylene oxide (having an ethylene group as the alkylene group), Z is a hydrogen atom, and the sum of l to n is approximately 20.

[0067] Comparative Example 3 A spectacle lens was produced and evaluated by the same method as in Example 1, except that in preparing the polymerizable composition for forming a protective layer, NK Ester A-BPE-10 (ethoxylated bisphenol A diacrylate) manufactured by Shin-Nakamura Chemical Co., Ltd. was used instead of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd.

[0068] Comparative Example 4 A spectacle lens was produced and evaluated by the same method as in Example 1, except that A-DCP (tricyclodecane dimethanol diacrylate) manufactured by Shin-Nakamura Chemical Co., Ltd. was used instead of NK Ester A-DPH-12E manufactured by Shin-Nakamura Chemical Co., Ltd. in the preparation of the polymerizable composition for forming a protective layer.

[0069] The results are shown in the following table. In the table, "wt%" means "mass%." The "oxyalkylene structure content in the solid content of the composition" and the "(meth)acryloyl group concentration in the solid content of the composition" shown in the table are values ​​calculated from the composition of each composition of the examples and comparative examples.

[0070]

[0071]

[0072] From the results shown in the above table, it can be confirmed that the eyeglass lenses of Examples 1 to 5 have protective layers that are less susceptible to cracking, scratches are less visible, and there is little degradation in optical performance and photochromic performance due to the provision of the protective layer.

[0073] The various aspects and configurations described herein may be combined in any combination of two or more.

[0074] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0075] The present invention is useful in the technical fields of eyeglasses, goggles, sun visors, helmets, etc.

Claims

1. A curable composition for forming a protective layer of a photochromic article, satisfying the following requirements (1) to (3): (1) The composition contains a polyfunctional (meth)acrylate having an oxyalkylene structure; (2) The content of the oxyalkylene structure in the solid content of the composition is 20% by mass or more and 65% by mass or less; and (3) The concentration of (meth)acryloyl groups in the solid content of the composition is 4.0 mmol / g or more and 8.0 mmol / g or less.

2. A photochromic article having a photochromic layer containing a photochromic compound and a protective layer which is a cured layer obtained by curing the composition according to claim 1.

3. The photochromic article according to claim 2, wherein the protective layer has an indentation modulus of elasticity measured by a nanoindentation method of 1.0 GPa or more and 5.0 GPa or less.

4. The photochromic article according to claim 2, wherein the thickness of said protective layer is from 1 μm to 50 μm.

5. The photochromic article of claim 2, further comprising a substrate.

6. The photochromic article according to claim 5, comprising, in this order, the substrate, the photochromic layer, the protective layer, and the organosilicon-based cured layer.

7. The photochromic article according to claim 2, wherein the polyfunctional (meth)acrylate having an oxyalkylene structure is at least one selected from the group consisting of polyfunctional (meth)acrylates represented by the following formula 1 and polyfunctional (meth)acrylates represented by the following formula 2: (In Formula 1, X represents an oxyalkylene structure, and multiple Xs present in the molecule are the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule are the same or different. a to f each independently represent 1 or more, and the sum of a to f is the total number of oxyalkylene structures in the molecule.) (In Formula 2, R represents an oxyalkylene structure, and multiple Rs present in the molecule may be the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule may be the same or different. 1 to n each independently represent 1 or more, and the sum of 1 to n is the total number of oxyalkylene structures in the molecule.) 8. The photochromic article according to claim 2, wherein the indentation elastic modulus of the protective layer measured by nanoindentation is 1.0 GPa or more and 5.0 GPa or less, the thickness of the protective layer is 1 μm or more and 50 μm or less, the photochromic article has a substrate, the photochromic layer, the protective layer, and an organosilicon-based cured layer, in this order, and the polyfunctional (meth)acrylate having an oxyalkylene structure is one or more selected from the group consisting of polyfunctional (meth)acrylates represented by the following formula 1 and polyfunctional (meth)acrylates represented by the following formula 2: (In Formula 1, X represents an oxyalkylene structure, and multiple Xs present in the molecule are the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule are the same or different. a to f each independently represent 1 or more, and the sum of a to f is the total number of oxyalkylene structures in the molecule.) (In Formula 2, R represents an oxyalkylene structure, and multiple Rs present in the molecule may be the same or different oxyalkylene structures. Z represents a hydrogen atom or a methyl group, and multiple Zs present in the molecule may be the same or different. 1 to n each independently represent 1 or more, and the sum of 1 to n is the total number of oxyalkylene structures in the molecule.) 9. The photochromic article according to any one of claims 2 to 8, which is a spectacle lens.

10. The photochromic article according to any one of claims 2 to 8, which is a lens for goggles, a visor portion of a sun visor, or a shield member for a helmet.

11. Eyeglasses equipped with the eyeglass lenses according to claim 9.

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