Method of fabricating plastic lens

Abstract

To provide a plastic lens fabrication method which is superior in terms of work simplicity and productivity, and enables fabrication of plastic lenses with less thermal deformation.SOLUTION: A plastic lens fabrication method is provided, comprising a coating step of coating one surface of a lens base material with a photocurable composition, a curing step of curing the photocurable composition through light irradiation, and a temperature adjustment step of adjusting the ambient temperature to the range within -180 to 5°C before starting the light irradiation.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a plastic lens, and more particularly to a method for manufacturing a plastic lens that is easy to work with, has excellent productivity, and is capable of manufacturing a plastic lens that is less likely to be thermally deformed. [Background technology]

[0002] In the fields of eyeglass lenses, goggle lenses, etc., lenses having one or more properties are sometimes used, such as photochromic properties, anti-reflection properties, anti-fouling properties, and scratch resistance.

[0003] A method for imparting the above properties to a lens includes applying a photocurable composition that exhibits one or more of the above properties (for example, a polymerizable composition for forming a photochromic layer that contains a photochromic compound and a polymerizable compound) to the surface of a lens substrate, and then irradiating the applied photocurable composition with light to cure it, thereby forming a cured coating layer having the above properties. Note that by repeating this method multiple times, it is possible to produce a lens having multiple cured coating layers, i.e., a lens having multiple properties. However, curing a photocurable composition may require a large amount of light irradiation, and the heat generated by the light irradiation may cause the lens to deform significantly, making it unsuitable for use. Therefore, a method for producing lenses (including plastic lenses having one or more properties) that are less susceptible to thermal deformation is desired.

[0004] Patent Document 1 discloses a method of keeping the surface temperature of the lens substrate at 100°C or less when photocuring a photocurable composition applied to the surface of the lens substrate in order to suppress thermal deformation of the lens substrate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-012857 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the method described in Patent Document 1 controls the light intensity and irradiation time on the surface of the lens substrate, and therefore requires intermittent and long-term light irradiation, posing problems in terms of ease of operation and productivity.Furthermore, while it was possible to shorten the light irradiation time to some extent by combining this method with a method of cooling the lens substrate by contacting the back surface or even the sides of the lens substrate with a tube through which cold water is circulated, this resulted in a complex device structure and also presented problems such as uneven cooling effects occurring between the contact and non-contact areas of the tube and lens substrate.

[0007] An object of one aspect of the present disclosure is to provide a method for manufacturing a plastic lens that is easy to work with, has excellent productivity, and is capable of manufacturing a plastic lens that is less susceptible to thermal deformation. [Means for solving the problem]

[0008] The embodiments of the present disclosure relate to the following [1] to [6]. [1] A method for producing a plastic lens, comprising: a coating step of coating one surface of a lens substrate with a photocurable composition; a curing step of curing the photocurable composition by light irradiation; and a temperature adjustment step of adjusting the ambient temperature to -180 to 5°C before the start of the light irradiation. [2] The method for producing a plastic lens according to [1] above, wherein in the temperature adjustment step, the temperature is adjusted by introducing at least one selected from the group consisting of an inert liquid, an inert solid, and an inert gas. [3] The method for producing a plastic lens according to [2] above, wherein the inert gas is at least one selected from the group consisting of nitrogen gas, argon gas, and carbon dioxide gas. [4] The method for producing a plastic lens according to any one of the above [1] to [3], wherein the one surface is a convex surface and the other surface is a concave surface. [5] The method for producing a plastic lens according to any one of [1] to [4] above, wherein the photocurable composition is at least one selected from the group consisting of a polymerizable composition for forming a primer layer, a polymerizable composition for forming a photochromic layer, and a polymerizable composition for forming a protective layer. [6] The method for producing a plastic lens according to any one of [1] to [5] above, wherein the lens substrate has a thickness of less than 2 mm in a central portion and a peripheral portion that is thicker than the central portion.

[0009] As a result of extensive research into solving the above problems, the inventors discovered that the above problems can be solved by adjusting the ambient temperature to -180 to 5°C before initiating light irradiation to cure the photocurable composition applied to one surface of the lens substrate, and thus completed the present invention. Although the detailed mechanism by which the above method suppresses thermal deformation of plastic lenses is unknown, it is speculated that this is because adjusting the ambient temperature before the start of light irradiation can prevent the lens substrate, which has softened during light irradiation, from being pulled and deformed by the photocurable composition as it shrinks and hardens. [Effects of the Invention]

[0010] According to one aspect of the present disclosure, it is possible to provide a method for manufacturing a plastic lens that is easy to work with, has excellent productivity, and is capable of manufacturing a plastic lens that is less subject to thermal deformation. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is a top view schematically showing the UV curing chamber used in Example 1. [Figure 2] FIG. 2 is a side view schematically showing the UV curing chamber used in Example 1. [Figure 3] FIG. 10 is a side view schematically showing the UV curing chamber used in Example 5. [Figure 4] FIG. 2 is a side view schematically showing a UV curing chamber used in Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an example of an embodiment of the present disclosure will be described. However, the embodiment described below is an example for embodying the technical idea of ​​the present disclosure, and the present disclosure is not limited to the following description. Any selected or combined embodiment of the present disclosure and the matters described in this specification is also included in the present disclosure. In the present disclosure and specification, preferred definitions can be selected arbitrarily, and combinations of preferred definitions can be considered more preferred. In this disclosure and this specification, the expression "XX to YY" means "XX or more and YY or less." In the present disclosure and this specification, for preferred numerical ranges (e.g., ranges of content, etc.), the lower and upper limits described in stages can be independently combined. For example, the description "preferably 10 to 90, more preferably 30 to 60" can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60." Furthermore, in the numerical ranges described in the present disclosure and this specification, the upper or lower limit of the numerical range may be replaced with a value shown in the examples. In the present disclosure and this specification, a polymerizable composition refers to a composition containing a polymerizable compound. Also, a polymerizable compound refers to a compound having a polymerizable group. In the present disclosure and this specification, the term "cured coating layer" refers to a cured polymerizable composition; for example, a cured coating layer obtained by curing a polymerizable composition for forming a primer layer is called a primer layer, a cured coating layer obtained by curing a polymerizable composition for forming a photochromic layer is called a photochromic layer, a cured coating layer obtained by curing a polymerizable composition for forming a protective layer is called a protective layer, and a cured coating layer obtained by curing a polymerizable composition for forming a hard coat layer is called a hard coat layer. In this disclosure and this specification, "(meth)acrylate" encompasses 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. Furthermore, "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 a (meth)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 disclosure and this specification, the term "(meth)acryloyl group" is used to encompass both acryloyl groups and methacryloyl groups, and the term "(meth)acryloyloxy group" is used to encompass both acryloyloxy groups and methacryloyloxy groups. In this disclosure and this specification, unless otherwise specified, the groups described may have a substituent or may be unsubstituted. When a group has a substituent, examples of the substituent include an alkyl group (e.g., a linear alkyl group having 1 to 6 carbon atoms or a branched alkyl group having 1 to 6 carbon atoms), a hydroxyl 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, a carboxy group, an aryl group, a polyether group, etc. Furthermore, with respect to a group having a substituent, the "number of carbon atoms" refers to the number of carbon atoms in the portion excluding the substituent. In the present disclosure and this specification, the term "straight-chain alkyl group or branched alkyl group" does not include a cycloalkyl group. The straight-chain alkyl group or branched alkyl group may be unsubstituted or may have a substituent. It is acceptable for the straight-chain alkyl group or branched alkyl group to have a cycloalkyl group (e.g., a cyclohexyl group) as a substituent. In one embodiment, it is preferable that the straight-chain alkyl group or branched alkyl group does not have a cycloalkyl group as a substituent. In this disclosure and this specification, the "viscosity" is a value measured by a vibration viscometer in an atmospheric atmosphere at a temperature of 25°C. In this disclosure and this specification, the term "total amount" refers to the total amount of all components excluding the solvent, when the solvent is included. In this disclosure and specification, the term "central portion of the lens substrate" refers to the portion of the lens substrate having a radius of 5 mm or less from the center thereof. In this disclosure and this specification, the term "peripheral portion of the lens substrate" refers to the outermost peripheral portion of the lens substrate (a portion having a radius of 15 mm or more from the center of the lens substrate). The term "plastic lens" used in this disclosure and this specification may be a finished lens or a semi-finished lens. Note that a semi-finished lens is processed by polishing or grinding into a lens for actual use. In this disclosure and this specification, the term "finished lens" refers to a semi-finished lens that has been processed by polishing or grinding into a lens for actual use, or a lens molded into a lens for actual use. In this disclosure and this specification, the "thickness of the lens substrate" refers to the value measured by connecting terminals to the convex and concave surfaces of the lens substrate using a high-performance ABS Digimatic Indicator (ID-FNX series, manufactured by Mitutoyo Corporation). In this disclosure and this specification, the "thickness of the cured coating layer" refers to a value calculated by measuring the reflectance (interference waveform) of a sample using a non-contact film thickness measuring device (FF8 series, manufactured by System Road Co., Ltd.) and analyzing the film thickness value using FFT (fast Fourier transform). "Solids" in this disclosure and this specification refers to non-volatile matter excluding volatile substances such as solvents, and includes liquid, starch syrup-like, and wax-like substances at room temperature. The total solids content can also be calculated from the amount charged. "Room temperature" in this disclosure and this specification refers to the ambient temperature without temperature control such as heating or cooling, and is generally around 20°C, but is not limited to the above range as this can vary depending on the weather and season. The "intensity of light irradiation" in this disclosure and this specification is a value measured using a light meter (UIT-250, manufactured by USHIO Corporation) by lighting a lens base 300 mm away from the center of the light source to the light receiving unit (center wavelength 365 mm). The term "exposure amount of light irradiation" in this disclosure and this specification refers to the integrated value of irradiation time (intensity of light irradiation (mW / cm)) measured by using a light meter (UIT-250, manufactured by USHIO Corporation) to illuminate a lens base 300 mm away from the center of the light source to the light receiving unit (center wavelength 365 mm). 2 ) × irradiation time (seconds). In this disclosure and this specification, the "surface temperature of the lens after light irradiation" refers to the value measured using a radiation thermometer (TMHX-CNE0500 series, manufactured by Japan Sensor Co., Ltd., emissivity 0.95) at the point of the lens substrate closest to the light source (the center of the lens substrate) after the UV curing process has been completed.

[0013] [Plastic lens manufacturing method] Hereinafter, a method for producing a plastic lens according to one embodiment of the present disclosure is not particularly limited as long as it includes a coating step of coating one surface of a lens substrate with a photocurable composition, a curing step of curing the photocurable composition by light irradiation, and a temperature adjustment step of adjusting the ambient temperature to −180 to 5° C. before the start of light irradiation, and may further include other steps as necessary. Each step will be described in more detail below.

[0014] <Coating process> The coating step in the method for producing a plastic lens according to one embodiment of the present disclosure is a step of coating one surface of a lens substrate with a photocurable composition, and may or may not include other treatments. The coating step is a step carried out before the curing step, and may or may not be carried out in the same furnace as the curing step described below.

[0015] The method for applying the photocurable composition is not particularly limited, and examples thereof include known application methods such as spin coating, spray coating, dip coating, and dip-spin coating. These may be used alone or in combination of two or more. Among these, spin coating is preferred from the viewpoint of uniformity of application.

[0016] The rotation speed in spin coating is not particularly limited and is preferably 1 to 6000 rpm, more preferably 10 to 5000 rpm, and particularly preferably 50 to 4000 rpm. If the rotation speed is equal to or higher than the lower limit of the above range, coating becomes easier, and if the rotation speed is equal to or lower than the upper limit of the above range, thin film formation becomes easier.

[0017] The coating step may or may not include other treatments as necessary in addition to coating one surface of the lens substrate with the photocurable composition. The other treatment in the coating step is not particularly limited, and examples thereof include pretreatment carried out prior to coating of the photocurable composition. The pretreatment is preferably carried out from the viewpoint of improving adhesion between the cured coating layer of the photocurable composition and the lens substrate.

[0018] One form of the pretreatment is not particularly limited, and examples thereof include chemical treatment with a basic aqueous solution or an acidic aqueous solution, polishing treatment using an abrasive, plasma treatment using atmospheric pressure plasma or low pressure plasma, corona discharge treatment, UV ozone treatment, etc. These may be used alone or in combination of two or more.

[0019] (lens substrate) The lens substrate will be described in more detail below.

[0020] In the present disclosure and specification, the material for the lens substrate is not particularly limited and includes, for example, (meth)acrylic resin; styrene resin; polycarbonate resin; allyl resin; allyl carbonate resin such as diethylene glycol bisallyl carbonate resin (CR-39); vinyl resin; polyester resin; polyether resin; urethane resin obtained by reacting an isocyanate compound with a hydroxy compound such as diethylene glycol; thiourethane resin obtained by reacting an isocyanate compound with a polythiol compound; 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; oxides such as boric oxide, aluminum oxide, and silicon oxide. These may be used alone or in combination of two or more.

[0021] The type of the lens substrate is not particularly limited, and examples thereof include lens substrates used in spectacles and lens substrates used in goggles.

[0022] The color of the lens substrate is not particularly limited, and it may be colorless (an undyed lens) or dyed.

[0023] The refractive index of the lens substrate is not particularly limited and may be, for example, 1.50 to 1.75, etc. In this disclosure and this specification, the refractive index refers to the refractive index for light of mercury e-line at 546.07 nm.

[0024] The focal point of the lens substrate is not particularly limited, and examples thereof include single-focus, multi-focus, and progressive-addition lenses.

[0025] The surface of the lens substrate is not particularly limited, and examples thereof include a convex surface, a concave surface, a flat surface, etc. In a typical lens substrate, the object-side surface is a convex surface and the eyeball-side surface is a concave surface, but the present disclosure is not limited to this.

[0026] There are no particular restrictions on the thickness of the central portion of the lens substrate, but from the viewpoint of optical design, it is preferably less than 9.1 mm, more preferably 0.8 to 2.4 mm, and particularly preferably 0.8 to less than 2.0 mm. There are no particular restrictions on the thickness of the peripheral portion of the lens substrate, but from the viewpoint of optical design, it is preferably thicker than the central portion, more preferably 0.8 to 16.5 mm, and particularly preferably 1.6 to 13.0 mm.

[0027] There are no particular limitations on the one surface of the lens substrate, and examples thereof include a convex surface, a concave surface, and a flat surface. The other surface of the lens substrate is not particularly limited, and may be, for example, a convex, concave, or flat surface. In one form, one surface of the lens substrate onto which the photocurable composition is applied can be convex, and the other surface of the lens substrate can be concave.

[0028] (Photocurable composition) The photocurable composition will be described in more detail below.

[0029] In this disclosure and this specification, a photocurable composition is a polymerizable composition that has the property of being cured by irradiation with light, and is a composition that, after curing, exhibits one or more properties such as photochromic properties, antireflection properties, antifouling properties, scratch resistance, etc. By forming one or more cured coating layers, which are cured products of the photocurable compositions, on the surface of a lens substrate, the plastic lens can acquire properties such as photochromic properties, antireflection properties, antifouling properties, scratch resistance, etc.

[0030] The photocurable composition is not particularly limited, and examples thereof include a polymerizable composition for forming a primer layer, a polymerizable composition for forming a photochromic layer, a polymerizable composition for forming a protective layer, a polymerizable composition for forming a hard coat layer, etc. These may be used alone or in combination of two or more. The polymerizable composition for forming a primer layer, the polymerizable composition for forming a photochromic layer, and the polymerizable composition for forming a protective layer will be described in further detail below.

[0031] ((Polymerizable composition for forming primer layer)) Examples of the form of the polymerizable composition for forming the primer layer (hereinafter sometimes simply referred to as "primer layer composition") include (i) a primer layer composition containing a polyurethane resin and a solvent for the polyurethane resin, and (ii) a primer layer composition containing a polyisocyanate, a hydroxy group-containing polymerizable compound, and at least one polymerizable compound selected from the group consisting of (meth)acrylates and vinyl ethers, having a viscosity of 100 cP or less. There are no particular restrictions on the components contained in the primer layer composition, but from the viewpoints of film hardness and ease of handling, including storage, a primer layer composition containing (i) a polyurethane resin and a solvent for the polyurethane resin is preferred. On the other hand, from the viewpoints of suppressing attenuation of photochromic properties resulting from the primer layer, which is a cured product of the primer layer composition, and of adhesion between the primer layer and other cured coating layers, (ii) a polymerizable compound which is at least one type selected from the group consisting of polyisocyanate, a hydroxy group-containing polymerizable compound, (meth)acrylate, and vinyl ether, and which has a viscosity of 100 cP or less, is preferred. The various components contained in the primer layer composition will be described in more detail below.

[0032] -Polyurethane resin- Specific examples of polyurethane resins are not particularly limited, and include, for example, moisture-curing primer polyurethane resins (manufactured by Mitsui Takeda Chemicals, Inc., "Takenate M-605N") and "Takenate M-402P", etc. These may be used alone or in combination of two or more. Among these, a moisture-curable primer polyurethane resin ("Takenate M-605N" manufactured by Mitsui Takeda Chemicals Inc.) is preferred from the viewpoint of application properties or wettability of the photochromic composition during application.

[0033] The isocyanate group content of the polyurethane resin determined by the amine equivalent method is not particularly limited, but from the viewpoint of adhesion, it is preferably 0.1 to 10.0 mol %, more preferably 0.5 to 5.0 mol %, and particularly preferably 1.0 to 3.0 mol %. The amine equivalent method is specified in JIS K 1603-1:2007.

[0034] -Solvent for polyurethane resin- The solvent for polyurethane resin is not particularly limited, and examples thereof include butyl acetate, ethyl acetate, etc. These may be used alone or in combination of two or more. Among these, butyl acetate is preferred from the viewpoint of volatility.

[0035] The mass ratio of polyurethane resin to solvent for polyurethane resin (polyurethane resin:solvent for polyurethane resin) is not particularly limited, but from the viewpoint of resin dispersibility, it is preferably 10:90 to 90:10, more preferably 30:70 to 70:30, and particularly preferably 40:60 to 60:40.

[0036] -Polyisocyanate- The polyisocyanate is a compound having two or more isocyanate groups in one molecule. The number of isocyanate groups contained in one molecule of the polyisocyanate is not particularly limited, but is preferably 2 to 6, more preferably 3 to 5, and particularly preferably 3 to 4. When the number is equal to or greater than the lower limit of the above range, the water resistance of the primer layer is likely to be improved, and when the number is equal to or less than the upper limit of the above range, adhesion to the lens substrate is likely to be improved.

[0037] The molecular weight of the polyisocyanate is not particularly limited, but is preferably 200 to 800, more preferably 300 to 700, and particularly preferably 400 to 600. If the molecular weight is equal to or greater than the lower limit of the above range, adhesion to the lens substrate is facilitated, and if the molecular weight is equal to or less than the upper limit of the above range, the water resistance of the primer layer is likely to be improved.

[0038] Specific examples of the polyisocyanate are not particularly limited and include, for example, aromatic diisocyanates such as xylylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and naphthalene diisocyanate; aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,3-bisisocyanatomethylcyclohexane, and tetramethylxylylene diisocyanate; etc. These may be used alone or in combination of two or more. The polyisocyanates exemplified above may be allophanate, adduct, biuret, or isocyanurate, and these may be used alone or in combination of two or more. Furthermore, commercially available polyisocyanates include, but are not limited to, Coronate HX, Coronate HXR, Coronate HXLV, Coronate HK, Coronate 2715, Coronate HL, Coronate L, Coronate 2037, HDI, TDI, and MDI (manufactured by Tosoh Corporation), Takenate 500, Takenate 600, Duranate 24A-100, TPA-100, TKA-100, P301-75E, and Takenate D-110N, D-120N, D-127N, D-140N, D-160N, D15N, D-170N, D-170HN, D-172N, D-177N, D-178N, and D-101E (manufactured by Mitsui Chemicals, Inc.). These may be used alone or in combination of two or more.

[0039] -Hydroxy group-containing polymerizable compound- The number of hydroxy groups contained in one molecule of the hydroxy group-containing polymerizable compound is not particularly limited, but is preferably 1 to 6, more preferably 1 to 5, and particularly preferably 2 to 4. When the number is equal to or greater than the lower limit of the above range, the reaction efficiency with polyisocyanate tends to be good, and when the number is equal to or less than the upper limit of the above range, adhesion to the photochromic layer tends to be good. The present inventors speculate that the urethane bond formed by reacting the isocyanate group of the polyisocyanate with the hydroxy group of the hydroxy group-containing polymerizable compound contributes to improving the adhesion of the primer layer.

[0040] The number of polymerizable groups contained in one molecule of the hydroxy group-containing polymerizable compound is not particularly limited, but is preferably 2 or more from the viewpoint of the efficiency of the polymerization reaction.

[0041] One example of the hydroxy group-containing polymerizable compound is a (meth)acrylate. When the hydroxy group-containing polymerizable compound is a (meth)acrylate, the number of functional groups of the (meth)acrylate is not particularly limited, but from the viewpoint of adhesion, it is preferably 1 (monofunctional) to 3, more preferably 2 to 3. The (meth)acryloyl group, which is the functional group, may contain only an acryloyl group, may contain only a methacryloyl group, or may contain an acryloyl group and a methacryloyl group. In one embodiment, from the viewpoint of adhesion, it is preferable that the hydroxy group-containing polymerizable compound contains only an acryloyl group as the (meth)acryloyl group.

[0042] The molecular weight of the hydroxy group-containing polymerizable compound is not particularly limited, but is preferably 100 to 600, more preferably 200 to 500, and particularly preferably 300 to 400. When the molecular weight is equal to or greater than the lower limit of the above range, the reaction efficiency with the polyisocyanate tends to be good, and when the molecular weight is equal to or less than the upper limit of the above range, adhesion to the photochromic layer tends to be good.

[0043] Specific examples of the (meth)acrylate are not particularly limited and include, for example, 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 1,4-cyclohexanedimethanol monoacrylate, 2-hydroxy-1-acryloxy-3-methadryloxypropane, 2-hydroxy-1,3-dimethacryloxypropane, pentaerythritol tetraacrylate, 2-hydroxy-3-phenoxypropyl acrylate, monoacryloxyethyl hexahydrophthalate, 2-acryloyloxyethyl phthalate, 2-(acryloxyoxy)ethyl 2-hydroxyethyl phthalate, and compounds represented by the following formula (1): These may be used alone or in combination of two or more.

[0044] [ka] ···(1)

[0045] One embodiment of the hydroxy group-containing polymerizable compound is a hydroxy group-containing polymerizable compound having an amide group. The hydroxy group-containing polymerizable compound having an amide group is not particularly limited, and examples thereof include N-(2-hydroxyethyl)acrylamide.

[0046] One example of the hydroxyl group-containing polymerizable compound is a hydroxyl group-containing polymerizable compound having an epoxy ester structure, which is a structure formed by the reaction of an epoxy group with a carboxyl group and can be represented by "-CH(OH)-CH-OC(=O)-". Commercially available hydroxyl group-containing polymerizable compounds having an epoxy ester structure are not particularly limited, and examples thereof include Epoxy Ester 40EM (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 70PA (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 80MFA (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 200PA (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 3002M(N) (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 3002A(N) (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 3000MK (Kyoeisha Chemical Co., Ltd.), Epoxy Ester 3000A (Kyoeisha Chemical Co., Ltd.), etc. These may be used alone or in combination of two or more.

[0047] -A polymerizable compound which is at least one selected from the group consisting of (meth)acrylates and vinyl ethers and has a viscosity of 100 cP or less- The primer layer composition preferably contains at least one polymerizable compound selected from the group consisting of (meth)acrylates and vinyl ethers, and having a viscosity of 100 cP (centipoise) or less (hereinafter, sometimes simply referred to as a "low-viscosity polymerizable compound"). The present inventors speculate that a primer layer composition containing the low-viscosity polymerizable compound suppresses attenuation of photochromic properties caused by the primer layer.

[0048] The viscosity of the low-viscosity polymerizable compound is not particularly limited as long as it is 100 cP or less, but from the viewpoint of ease of handling and suppression of the occurrence of optical defects, it is preferably 5 to 70 cP, more preferably 10 to 50 cP.

[0049] The number of functional groups in the (meth)acrylate, which is one form of the low-viscosity polymerizable compound, is not particularly limited, but is preferably 1 (monofunctional) to 3, more preferably 1 (monofunctional) to 2, from the viewpoint of adhesion. The (meth)acrylate, which is one form of the low-viscosity polymerizable compound, can contain an aryl group (e.g., a phenyl group), an amide group, etc. In the present disclosure and this specification, a "vinyl ether" refers to a compound having one or more vinyl groups and one or more ether bonds in one molecule, preferably two or more vinyl groups in one molecule, and more preferably two to four vinyl groups in one molecule. In addition, the number of ether bonds contained in the vinyl ether is preferably two to four in one molecule.

[0050] The molecular weight of the low-viscosity polymerizable compound is not particularly limited, but is preferably 100 to 300, and more preferably 150 to 250. When the molecular weight is equal to or greater than the lower limit of the above range, the occurrence of optical defects is easily suppressed, and when the molecular weight is equal to or less than the upper limit of the above range, adhesion to the photochromic layer is easily achieved.

[0051] Specific examples of the low viscosity polymerizable compound are not particularly limited, and include, for example, 2-phenoxyethyl (meth)acrylate, acrylamide, methoxypolyethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, stearyl (meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, phenoxyethyl (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, Trimethylolpropane tri(meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, diethylene glycol butyl ether (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate Acrylate, 2-phenoxyethyl (meth)acrylate, isobornyl (meth)acrylate, 2-(dimethylamino)ethyl (meth)acrylate, 2-(diethylamino)ethyl (meth)acrylate, glycidyl (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tetramethylene glycol di(meth)acrylate, neopentyl glycol Examples of suitable vinyl ethers include butyl di(meth)acrylate, hexanediol di(meth)acrylate, nonamethylene glycol di(meth)acrylate, isoamyl (meth)acrylate, ethylene glycol monovinyl ether, tetramethylene glycol monovinyl ether, diethylene glycol monovinyl ether, 2-ethylhexyl vinyl ether, 2-propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester, and 2-(2-ethenoxyethoxy)ethyl 2-methylprop-2-enoate. These may be used alone or in combination of two or more.

[0052] The content of the low-viscosity polymerizable compound is not particularly limited, but is preferably 30.0 to 90.0 mass%, more preferably 35.0 to 80.0 mass%, and particularly preferably 40.0 to 70.0 mass%, relative to 100 mass% of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound. When the thickness is equal to or greater than the lower limit of the above range, the film is easy to handle, and when the thickness is equal to or less than the upper limit of the above range, the film is easily adhered to the lens substrate. In one embodiment of the content of the low-viscosity polymerizable compound, the low-viscosity polymerizable compound is the component that is contained in the largest amount in the composition for primer layer that contains the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound.

[0053] The content of the polyisocyanate is not particularly limited, but is preferably 10.0 to 70.0 mass%, more preferably 20.0 to 60.0 mass%, and particularly preferably 30.0 to 50.0 mass%, relative to 100 mass% of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound. When the thickness is equal to or greater than the lower limit of the above range, the water resistance of the primer layer is likely to be improved, and when the thickness is equal to or less than the upper limit of the above range, adhesion to the lens substrate is likely to be improved.

[0054] The content of the hydroxy group-containing polymerizable compound is not particularly limited, but is preferably 3.0 to 30.0 mass%, more preferably 5.0 to 25.0 mass%, and particularly preferably 7.0 to 20.0 mass%, relative to 100 mass% of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound. When the content is equal to or greater than the lower limit of the above range, the reaction efficiency with the polyisocyanate tends to be good, and when the content is equal to or less than the upper limit of the above range, adhesion to the photochromic layer tends to be good.

[0055] The primer layer composition may further contain a polymerization initiator, if necessary. The amount of the polymerization initiator to be added is not particularly limited, and from the viewpoint of primer layer formation efficiency, it is preferably 0.01 to 3.0 parts by mass per 100 parts by mass of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound.

[0056] The polymerization initiator is not particularly limited, and known polymerization initiators can be used. The known polymerization initiator is not particularly limited, and examples thereof include photoradical polymerization initiators, thermal polymerization initiators, etc. These may be used alone or in combination of two or more. Among these, photoradical polymerization initiators are preferred from the viewpoint of progressing the polymerization reaction in a short time. For specific examples of the photoradical polymerization initiator, reference can be made to the polymerization initiators that can be contained in the polymerizable composition for forming a photochromic layer, which will be described later.

[0057] The composition for primer layer may or may not contain a solvent other than the solvent for the polyurethane resin. When the composition for primer layer contains a solvent other than the solvent for polyurethane resin, the solvent is not particularly limited, and any solvent can be used as long as it does not inhibit the progress of the polymerization reaction of the polymerizable composition. When the primer layer composition contains a solvent other than the solvent for the polyurethane resin, the amount of the solvent is not particularly limited, but from the viewpoint of suppressing the occurrence of optical defects, the amount of the solvent is preferably 10.0 parts by mass or less, more preferably 5.0 parts by mass or less, and particularly preferably 3.0 parts by mass or less, per 100 parts by mass of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound.

[0058] The primer layer composition may further contain, as necessary, known additives that can usually be added to compositions for forming primer layers. The amount of the known additives to be added is not particularly limited as long as the effect of the primer layer is exhibited, and is preferably 1.0 to 20.0 parts by mass, more preferably 1.5 to 10.0 parts by mass, and particularly preferably 2.0 to 5.0 parts by mass, relative to 100 parts by mass of the total of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound.

[0059] The contents of the low-viscosity polymerizable compound, polyisocyanate, and hydroxy group-containing polymerizable compound are not particularly limited as long as they exhibit the effect of the primer layer, and are preferably 80.0 to 100.0 mass%, more preferably 85.0 to 100.0 mass%, and more preferably 90.0 to 100.0 mass%, based on 100 mass% of the primer layer composition (excluding the polymerization initiator).

[0060] The primer layer composition can be prepared by mixing the various components described above simultaneously or sequentially in any order.

[0061] The primer layer composition is irradiated with light and cured to obtain a primer layer, which is a cured coating layer. The primer layer has the function of improving the adhesion between the cured coating layers located on both surfaces of the primer layer, the adhesion between the lens substrates, and the adhesion between the cured coating layer and the lens substrate. The location of the primer layer is not particularly limited, but from the viewpoint of improving adhesion between the lens substrate and the cured coating layer (e.g., photochromic layer), it is preferably between the lens substrate and the cured coating layer (e.g., photochromic layer).

[0062] The thickness of the primer layer is not particularly limited, but is preferably 1 to 20 μm, more preferably 2 to 15 μm, and particularly preferably 3 to 10 μm. If the thickness is at least the lower limit of the above range, adhesion between the lens substrate and the photochromic layer will be good, and if the thickness is at most the upper limit of the above range, invasion of the photochromic layer will be more easily suppressed.

[0063] ((Photochromic Layer-Forming Polymerizable Composition)) One embodiment of the photochromic layer-forming polymerizable composition (hereinafter sometimes simply referred to as "photochromic layer composition") is a photochromic layer composition containing two or more (meth)acrylates and a photochromic compound. The two or more (meth)acrylates function as polymerizable compounds in the photochromic layer composition. The various components contained in the composition for the photochromic layer will be described in more detail below.

[0064] -Two or more types of (meth)acrylate- The two or more (meth)acrylates are not particularly limited, but from the viewpoint of fading speed, it is preferable to include at least a polyfunctional (meth)acrylate having a molecular weight of 500 or more (hereinafter, sometimes referred to as "component A"). The (meth)acrylate other than Component A among the two or more (meth)acrylates is not particularly limited, and examples thereof include a monofunctional (meth)acrylate (hereinafter sometimes referred to as "Component B"), a polyfunctional (meth)acrylate having neither a cyclic structure nor a branched structure (hereinafter sometimes referred to as "Component C"), a bifunctional (meth)acrylate having at least one structure selected from the group consisting of a cyclic structure and a branched structure (hereinafter sometimes referred to as "Component D"), etc. These may be used alone or in combination of two or more.

[0065] --Component A-- The molecular weight of the above component A is not particularly limited as long as it is 500 or more, but is preferably 600 to 2000, more preferably 650 to 1500, and particularly preferably 700 to 1300. If it is equal to or greater than the lower limit of the above range, the fading speed tends to be improved, and if it is equal to or less than the upper limit of the above range, the photochromic layer tends to have a high hardness.

[0066] The component A is not particularly limited, and examples thereof include bifunctional (meth)acrylates, trifunctional (meth)acrylates, tetrafunctional (meth)acrylates, and pentafunctional (meth)acrylates. These may be used alone or in combination of two or more. Among these, from the viewpoint of weather resistance, bifunctional or trifunctional (meth)acrylates are preferred. The (meth)acryloyl group of the above-mentioned component A may contain only acryloyl groups, only methacryloyl groups, or both acryloyl groups and methacryloyl groups. That is, component A can be an acrylate or a methacrylate.

[0067] One embodiment of the above-mentioned component A includes acyclic polyfunctional (meth)acrylates. In this disclosure and this specification, "acyclic" means not containing a cyclic structure. In contrast, "cyclic" means containing a cyclic structure. The acyclic polyfunctional (meth)acrylate refers to a bifunctional or higher functional (meth)acrylate that does not contain a cyclic structure. Specific examples of Component A are not particularly limited and include, for example, polyalkylene glycol di(meth)acrylates represented by the following formula (2): These may be used alone or in combination of two or more.

[0068] [ka] ···(2)

[0069] In formula (2), R 1 and R 2 each independently represents a hydrogen atom or a methyl group, R represents an alkylene group, and n represents the number of repetitions of the alkoxy group represented by RO and is 2 or more. The number of carbon atoms in the alkylene group represented by R in formula (2) is not particularly limited, but is preferably 1 to 5, and more preferably 2 to 4. The alkylene group represented by R in formula (2) is not particularly limited, and examples thereof include an ethylene group, a propylene group, and a tetramethylene group. Although n in formula (2) is not particularly limited, it is preferably 2-30, more preferably 2-25, and particularly preferably 2-20. The polyalkylene glycol di(meth)acrylate represented by formula (2) is not particularly limited, and examples thereof include polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0070] Furthermore, a specific example of component A is a tri(meth)acrylate represented by the following formula (3). The (meth)acryloyl group of the tri(meth)acrylate represented by formula (3) may contain only acryloyl groups, may contain only methacryloyl groups, or may contain acryloyl groups and methacryloyl groups.

[0071] [ka] ···(3)

[0072] In formula (3), R 40 , R 41 , R 44 , R 45 , R 47 and R 48 each independently represents an alkylene group, R 43 represents an alkyl group, and R 42 , R 46 and R 49 each independently represents a hydrogen atom or a methyl group. In formula (3), n1 is OR 41 The number of repetitions of the alkoxy group represented by the formula (I) is 2 or more. In formula (3), n2 is OR 45 The number of repetitions of the alkoxy group represented by the formula (I) is 2 or more. In formula (3), n3 is OR 48 The number of repetitions of the alkoxy group represented by the formula (I) is 2 or more.

[0073] R in Equation (3) 41 , R 45 and R 48 The n1, n2, and n3 in formula (3) are as described above for n in formula (2). In formula (3), R 41 , R 45 and R 48 may be the same, or two or three may be different. This also applies to n1, n2, and n3.

[0074] R in Equation (3) 42 , R 46 and R 49 each independently represents a hydrogen atom or a methyl group. The tri(meth)acrylate represented by formula (3) may contain only acryloyl groups, only methacryloyl groups, or both acryloyl groups and methacryloyl groups as (meth)acryloyl groups.

[0075] R in Equation (3) 43 The number of carbon atoms in the alkyl group represented by the formula (I) is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 4. R in Equation (3) 43 The alkyl group represented by the formula (I) is a straight-chain alkyl group or a branched alkyl group. R in Equation (3) 43 Specific examples of the alkyl group represented by the formula (I) are not particularly limited, and include, for example, a methyl group and an ethyl group.

[0076] R in Equation (3) 40 , R 44 and R 47 each independently represents an alkylene group. R in Equation (3) 40 , R 44 and R 47 The number of carbon atoms in the alkylene group represented by the following formula is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 4. R in Equation (3) 40, R 44 and R 47 Specific examples of the alkylene group represented by the formula (I) are not particularly limited, and include, for example, a methylene group, an ethylene group, a propylene group, and a tetramethylene group.

[0077] The tri(meth)acrylate represented by formula (3) is not particularly limited, and examples thereof include trimethylolpropane polyoxyethylene ether tri(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0078] --Component B-- Component B is a monofunctional (meth)acrylate represented by the following formula (4).

[0079] [ka] ···(4)

[0080] In formula (4), R 10 represents a hydrogen atom or a methyl group. The monofunctional (meth)acrylate represented by formula (4) may be an acrylate or a methacrylate.

[0081] In formula (4), R 11 represents a linear alkyl group having 3 or more carbon atoms or a branched alkyl group having 3 or more carbon atoms. R in Equation (4) 11 The alkyl group represented by the formula (I) may be unsubstituted or may have a substituent. The substituent is not particularly limited, and examples thereof include the various substituents described above. R in Equation (4) 11 The number of carbon atoms in the linear or branched alkyl group represented by the formula (I) is not particularly limited, but is preferably 3 to 15, more preferably 3 to 14, and particularly preferably 3 to 12. If the content is equal to or greater than the lower limit of the above range, the color density of the photochromic layer tends to be high, whereas if the content is equal to or less than the upper limit of the above range, the photochromic compound tends to dissolve in the composition for the photochromic layer.

[0082] The molecular weight of the monofunctional (meth)acrylate represented by formula (4) may be, for example, 100 to 300. However, it is not limited to the above range. As described above, in one embodiment, the monofunctional (meth)acrylate represented by formula (4) may be a monofunctional (meth)acrylate having a molecular weight of 150 or less. Specific examples of the monofunctional (meth)acrylate represented by formula (4) are not particularly limited and include, for example, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, n-lauryl (meth)acrylate, etc. These may be used alone or in combination of two or more.

[0083] The polyfunctional (meth)acrylate other than Component A that may be contained in the two or more (meth)acrylates is not particularly limited, but from the viewpoint of increasing the (meth)acryloyl group content in the composition for photochromic layer and forming a rigid polymer network between molecules, a (meth)acrylate with a high proportion of (meth)acryloyl groups in the molecule is preferred. From this viewpoint, a polyfunctional (meth)acrylate with a smaller molecular weight than Component A is preferred. The molecular weight of the polyfunctional (meth)acrylate other than the above component A is not particularly limited, but from the above viewpoint, it is preferably 100 or more and less than 500, more preferably 100 or more and 400 or less, and particularly preferably 100 or more and 350 or less. The number of functional groups of the polyfunctional (meth)acrylate other than Component A is not particularly limited, but from the viewpoint of weather resistance, a polyfunctional (meth)acrylate having a larger number of functional groups than the polyfunctional (meth)acrylate used as Component A is preferred. The number of functional groups of the polyfunctional (meth)acrylate can be, for example, 10 to 15. There is no particular limit to the polyfunctional (meth)acrylate having 10 to 15 functional groups, and examples thereof include poly[(3-methacryloyloxypropyl)silsesquioxane] derivatives. These may be used alone or in combination of two or more.

[0084] The polyfunctional (meth)acrylate is not particularly limited, and examples thereof include a polyfunctional (meth)acrylate having neither a cyclic structure nor a branched structure (component C), a bifunctional (meth)acrylate having at least one structure selected from the group consisting of a cyclic structure and a branched structure (component D), etc. These may be used alone or in combination of two or more. Components C and D will be described in more detail below.

[0085] --Component C-- Component C is a polyfunctional (meth)acrylate having neither a cyclic structure nor a branched structure, represented by the following formula (5).

[0086] [ka] ···(5)

[0087] In formula (5), R 3 and R 4 each independently represents a hydrogen atom or a methyl group. In formula (5), m represents an integer of 1 or more, and may be 10 or less, 9 or less, 8 or less, 7 or less, or 6 or less. When the above component C has a methacryloyl group, the branched structure contained in the methacryloyl group is not taken into consideration.

[0088] The molecular weight of the above-mentioned component C is not particularly limited, but is preferably 100 to 400, more preferably 140 to 350, and particularly preferably 160 to 300. If it is equal to or greater than the lower limit of the above-mentioned range, the fading speed tends to be improved, and if it is equal to or less than the upper limit of the above-mentioned range, the color density of the photochromic layer tends to be increased.

[0089] The above-mentioned component C may contain only acryloyl groups, only methacryloyl groups, or both acryloyl groups and methacryloyl groups as (meth)acryloyl groups. Specific examples of the component C are not particularly limited and include, for example, 1,9-nonanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0090] --Component D-- Component D is a bifunctional (meth)acrylate containing at least one structure selected from the group consisting of a cyclic structure and a branched structure. It is presumed that the inclusion of the above component D in the composition for photochromic layer contributes to improving the color density of the photochromic layer formed from the composition for photochromic layer. In one embodiment, the component D may contain one or more cyclic structures and no branched structures in one molecule, in another embodiment, one or more branched structures and no cyclic structures in one molecule, and in still another embodiment, one or more cyclic structures and one or more branched structures in one molecule. The number of at least one structure selected from the group consisting of cyclic structures and branched structures contained in the above component D is not particularly limited, but is preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1. When the above-mentioned component D has a methacryloyl group, the branched structure contained in the methacryloyl group is not taken into consideration.

[0091] One example of component D containing one or more cyclic structures is an alicyclic bifunctional (meth)acrylate. The alicyclic bifunctional (meth)acrylate is not particularly limited, and examples thereof include R 111 -(L 11 ) n11 -Q-(L 22 ) n22 -R 222 Examples of the compound include compounds having a structure represented by the following formula: where Q represents a divalent alicyclic group, and R 111 and R 222 each independently represents a (meth)acryloyl group or a (meth)acryloyloxy group, L 11and L 22 each independently represents a linking group; n11 and n22 each independently represents 0 or 1; The divalent alicyclic group represented by Q is not particularly limited, and suitable examples thereof include alicyclic hydrocarbon groups having 3 to 20 carbon atoms, such as a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a tricyclodecanylene group, and an adamantylene group. L 11 and L 22 The linking group represented by the following formula is not particularly limited, and examples thereof include alkylene groups having 1 to 6 carbon atoms.

[0092] Specific examples of alicyclic bifunctional (meth)acrylates are not particularly limited and include, for example, cyclohexanedimethanol di(meth)acrylate, ethoxylated cyclohexanedimethanol di(meth)acrylate, propoxylated cyclohexanedimethanol di(meth)acrylate, ethoxylated propoxylated cyclohexanedimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethoxylated tricyclodecane dimethanol di(meth)acrylate, propoxylated tricyclodecane dimethanol di(meth)acrylate, ethoxylated propoxylated tricyclodecane dimethanol di(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0093] One example of component D containing one or more branched structures is a bifunctional (meth)acrylate containing a branched alkylene group. The number of carbon atoms in the branched alkylene group is not particularly limited, but is preferably 1 to 10, more preferably 2 to 9, even more preferably 3 to 8, and particularly preferably 4 to 7. One form of the branched alkylene group may contain a quaternary carbon (i.e., a carbon bonded to four carbons). Specific examples of Component D containing one or more branched structures are not particularly limited and include, for example, neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, propoxylated neopentyl glycol di(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0094] The molecular weight of the above-mentioned component D is not particularly limited, but is preferably 200 to 400. When it is equal to or greater than the lower limit of the above-mentioned range, the color density of the photochromic layer is likely to be improved, and when it is equal to or less than the upper limit of the above-mentioned range, the photochromic compound is likely to be dissolved in the composition for the photochromic layer.

[0095] The above-mentioned component D may contain only acryloyl groups, only methacryloyl groups, or both acryloyl groups and methacryloyl groups as (meth)acryloyl groups.

[0096] The content of the polymerizable compound (i.e., the total content of multiple polymerizable compounds) is not particularly limited, but is preferably 70 to 99 mass %, more preferably 80 to 95 mass %, relative to 100 mass % of the composition for photochromic layer. If the content is equal to or greater than the lower limit of the above range, the photochromic compound becomes more easily soluble in the composition for photochromic layer, and if the content is equal to or less than the upper limit of the above range, the photochromic properties tend to be improved. The composition for photochromic layer may or may not contain a solvent. When the composition for photochromic layer contains a solvent, any solvent can be used in any amount as long as it does not inhibit the progress of the polymerization reaction of the polymerizable composition.

[0097] The content of Component A is not particularly limited, but is preferably 50 to 95% by mass, more preferably 55 to 92% by mass, and particularly preferably 60 to 90% by mass, based on 100% by mass of all polymerizable compounds contained in the composition for photochromic layer. When the content is equal to or greater than the lower limit of the above range, the fading rate is likely to be improved, and when the content is equal to or less than the upper limit of the above range, weather resistance is likely to be improved. In this disclosure and this specification, a component that corresponds to both Component A and Component C, or Component A and Component D, is considered to be Component A. In one form, Component A can be the component that accounts for the largest proportion of multiple polymerizable compounds contained in the composition. In one embodiment, the composition for photochromic layer may contain only one type of component A, and in another embodiment, it may contain two or more types of component A. When two or more types of component A are contained, the content of component A mentioned above is the total content of the two or more types. This also applies to the contents of other components.

[0098] The content of Component B is not particularly limited, but is preferably 1 to 30 mass %, more preferably 5 to 27 mass %, and particularly preferably 10 to 25 mass %, relative to 100 mass % of all polymerizable compounds contained in the composition for photochromic layer. When the content is equal to or greater than the lower limit of the above range, weather resistance is likely to be improved, and when the content is equal to or less than the upper limit of the above range, the fading rate is likely to be improved. In one embodiment, the composition for photochromic layer may contain only one type of component B, and in another embodiment, it may contain two or more types of component B. When two or more types of component B are contained, the content of component B mentioned above is the total content of the two or more types.

[0099] The content of Component C is not particularly limited, but is preferably 1 to 30 mass %, more preferably 3 to 27 mass %, based on 100 mass % of all polymerizable compounds contained in the composition for photochromic layer. If the content is equal to or greater than the lower limit of the above range, the color density tends to increase, and if it is equal to or less than the upper limit of the above range, the fading rate tends to increase. In one embodiment, the composition for photochromic layer may contain only one type of component C, and in another embodiment, it may contain two or more types of component C. When two or more types of component C are contained, the content of component C mentioned above is the total content of the two or more types.

[0100] The content of component D is not particularly limited, but is preferably 1 to 30 mass %, and more preferably 5 to 27 mass %, relative to 100 mass % of all polymerizable compounds contained in the composition for photochromic layer. If the content is equal to or greater than the lower limit of the above range, the color density of the photochromic layer is likely to be improved, and if the content is equal to or less than the upper limit of the above range, the photochromic compound is likely to dissolve in the composition for photochromic layer. In one embodiment, the composition for photochromic layer may contain only one type of component D, and in another embodiment, it may contain two or more types of component D. When two or more types of component D are contained, the content of component D above is the total content of the two or more types.

[0101] The composition for photochromic layer may or may not contain, as necessary, other (meth)acrylates other than Components A to D. When the composition contains other (meth)acrylates other than Components A to D, the content of the other (meth)acrylates other than Components A to D is not particularly limited, but from the viewpoint of the fading rate, it is preferably 10.0% by mass or less, and more preferably 5.0% by mass or less, relative to 100% by mass of all (meth)acrylates contained in the composition for photochromic layer. The composition for photochromic layer may or may not contain a polymerizable compound other than (meth)acrylate, as necessary.

[0102] -Photochromic Compounds- One embodiment of the composition for the photochromic layer may contain a photochromic compound together with the polymerizable compound. The photochromic compound is not particularly limited, and for example, any known compound that exhibits photochromic properties when exposed to ultraviolet light can be used. Specific examples of the photochromic compound include, but are not limited to, compounds having a known skeleton exhibiting photochromic properties, such as azobenzenes, spiropyrans, spirooxazines, naphthopyrans, indenonaphthopyrans, phenanthropyrans, hexaallylbismidazoles, donor-acceptor Stenhouse adducts (DASA), salicylideneanilines, dihydropyrenes, anthracene dimers, fulgides, diarylethenes, phenoxynaphthacenequinones, and stilbenes; fulgimide compounds; spirooxazine compounds; chromene compounds; indeno-fused naphthopyran compounds; and at least one compound selected from the group consisting of photochromic compounds represented by general formula A, general formula B, and general formula C, as described in WO2022 / 138966. These compounds may be used alone or in combination of two or more. The content of the photochromic compound is not particularly limited, but is preferably about 0.1 to 15% by mass relative to 100% by mass of the composition for photochromic layer.

[0103] -Other ingredients- The composition for photochromic layer may contain, in addition to two or more types of (meth)acrylate and a photochromic compound, one or more of various additives that may be typically contained in a polymerizable composition, in any amount, as needed. The additives that may be contained in the composition for photochromic layer are not particularly limited, and examples thereof include a polymerization initiator for promoting a polymerization reaction.

[0104] The polymerization initiator is not particularly limited, and any known polymerization initiator can be used, but a photoradical polymerization initiator is preferred, and more preferably, a polymerization initiator containing only a photoradical polymerization initiator. The polymerization initiator is not particularly limited, and examples thereof include a photoradical polymerization initiator and a thermal polymerization initiator. These may be used alone or in combination of two or more. Among these, a photoradical polymerization initiator is preferred from the viewpoint of progressing the polymerization reaction in a short time.

[0105] The photoradical polymerization initiator is not particularly limited, and examples thereof 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; 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, and 1,2-methyl-1-[4-(methyl α-Aminoketones such as 1-[(4-phenylthio)phenyl]-2-morpholinopropan-1-one; oxime esters such as 1-[(4-phenylthio)phenyl]-1,2-octadione-2-(benzoyl)oxime; phosphine oxides such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 2-(o-chlorophenyl)-4,5-diphenylimidazole 2,4,5-triarylimidazole dimers such as 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, N,N'-tetramethyl-4,4'-diaminobenzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxyphenyl benzophenone compounds such as 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;Examples of suitable compounds include 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; and coumarin. These compounds may be used alone or in combination of two or more. Among these, α-hydroxyketones and phosphine oxides are preferred from the viewpoints of curability, transparency, and heat resistance. In the 2,4,5-triarylimidazole dimer, the substituents of the aryl groups of the two triarylimidazole moieties may be the same, making the compound symmetrical, or different, making the compound asymmetrical.Furthermore, a thioxanthone compound may be combined with a tertiary amine, such as the combination of diethylthioxanthone and dimethylaminobenzoic acid. The content of the polymerization initiator is not particularly limited, but is preferably about 0.1 to 5.0% by mass relative to 100% by mass of the composition for photochromic layer.

[0106] If necessary, the composition for the photochromic layer may further contain any amount of known additives that are commonly added, such as surfactants, antioxidants, radical scavengers, light stabilizers, ultraviolet absorbers, color inhibitors, antistatic agents, fluorescent dyes, dyes, pigments, fragrances, plasticizers, and silane coupling agents. These may be used alone or in combination of two or more.

[0107] The composition for the photochromic layer can be prepared by mixing the various components described above simultaneously or sequentially in any order.

[0108] The photochromic layer composition is irradiated with light and cured to obtain a photochromic layer, which is a cured coating layer. The primer layer has a property of developing color under light in a predetermined wavelength range (for example, outdoors) and fading under light outside the predetermined wavelength range (for example, indoors), that is, photochromic property. The location of the photochromic layer is not particularly limited, but from the viewpoint of adhesion to the lens substrate and protection of the photochromic layer, it is preferably between the primer layer described above and the protective layer described below.

[0109] The thickness of the photochromic layer is not particularly limited, but is preferably 5 to 80 μm, more preferably 10 to 70 μm, and particularly preferably 15 to 60 μm. If the thickness is equal to or greater than the lower limit of the above range, the color density tends to become high, while if the thickness is equal to or less than the upper limit of the above range, transparency tends to be maintained.

[0110] ((Polymerizable composition for forming protective layer)) One embodiment of the above-mentioned polymerizable composition for forming a protective layer (hereinafter sometimes simply referred to as "protective layer composition") is a polymerizable composition containing one or more types of (meth)acrylate and containing 70.0% by mass or more of an alicyclic bifunctional (meth)acrylate relative to 100% by mass of all (meth)acrylates. The components contained in the protective layer composition are not particularly limited, but from the viewpoint of hardness and solvent resistance of the protective layer, it is preferable that the composition contains an alicyclic bifunctional (meth)acrylate.

[0111] As the alicyclic bifunctional (meth)acrylate contained in the composition for protective layer, reference can be made to the alicyclic bifunctional (meth)acrylate as an example of the polymerizable composition for forming a photochromic layer described above. The content of the alicyclic bifunctional (meth)acrylate is not particularly limited, but from the viewpoint of obtaining higher hardness and better solvent resistance of the protective layer, it is preferably 70.0 mass % or more, more preferably 75.0 mass % or more, even more preferably 85.0 mass % or more, and particularly preferably 95.0 mass % or more, based on 100 mass % of all (meth)acrylates. As one embodiment of the content of the alicyclic bifunctional (meth)acrylate, the total amount of (meth)acrylate may be alicyclic bifunctional (meth)acrylate.

[0112] In one embodiment of the protective layer composition, the (meth)acrylate may contain one or more other (meth)acrylates in addition to an alicyclic bifunctional (meth)acrylate. In another embodiment, the (meth)acrylate may contain only an alicyclic bifunctional (meth)acrylate. In the former embodiment, the other (meth)acrylate contained together with the alicyclic bifunctional (meth)acrylate is not particularly limited, and one or more of various (meth)acrylates may be used. Specific examples of the other (meth)acrylate are not particularly limited, and include, for example, monofunctional, bifunctional, trifunctional, tetrafunctional, and pentafunctional (meth)acrylates, which may be acyclic or cyclic. The (meth)acrylate containing a cyclic structure may have an alicyclic structure as the cyclic structure, or may have another cyclic structure. For the alicyclic structure, see the above description of the alicyclic bifunctional (meth)acrylate. The content of the other (meth)acrylates is not particularly limited, but from the viewpoint of obtaining high hardness and excellent solvent resistance in the protective layer of the present disclosure, the content is preferably 0 to 30.0 mass%, more preferably 1.0 to 25.0 mass%, and particularly preferably 5.0 to 20.0 mass% of all (meth)acrylates (100 mass%).

[0113] The composition for the protective layer contains at least one (meth)acrylate as a polymerizable compound, and in one embodiment, may contain one or more polymerizable compounds other than (meth)acrylate, or in another embodiment, may contain only (meth)acrylate as the polymerizable compound. The other polymerizable compound is not particularly limited, and one or more known polymerizable compounds may be used. The content of the above (meth)acrylate is not particularly limited, but from the viewpoint of durability, it is preferably 80.0% by mass or more, more preferably 90.0% by mass or more, and particularly preferably 100% by mass, of all polymerizable compounds in the composition for the protective layer (100% by mass).

[0114] In one embodiment, the content of the above (meth)acrylate (the total amount if two or more types of (meth)acrylates are included) is preferably 80.0% by mass or more, more preferably 90.0% by mass or more, and particularly preferably 95.0% by mass or more, based on 100% by mass of the composition for the protective layer.

[0115] The composition for a protective layer may or may not contain a solvent. When the composition for a protective layer contains a solvent, any solvent can be used in any amount without any particular limitation as long as it does not inhibit the progress of the polymerization reaction of the polymerizable composition.

[0116] The composition for a protective layer may further contain one or more additives in any content, as required. The additives are not particularly limited and include, for example, various known additives such as a polymerization initiator for promoting a polymerization reaction, a leveling agent for improving the coating suitability of the composition, etc. These may be used alone or in combination of two or more.

[0117] The polymerization initiator is not particularly limited, and examples thereof include photoradical polymerization initiators and thermal polymerization initiators. These may be used alone or in combination of two or more. Among these, photoradical polymerization initiators are preferred from the viewpoint of progressing the polymerization reaction in a short time. Specific examples of photoradical polymerization initiators can be found in the polymerization initiators that can be contained in the polymerizable composition for forming a photochromic layer described above. The content of the polymerization initiator is not particularly limited, but from the viewpoint of the efficiency of forming the protective layer, it is preferably 0.1 to 5.0% by mass in 100% by mass of the composition for protective layer.

[0118] The composition for the protective layer may further contain an ultraviolet absorber, if necessary. The ultraviolet absorber is not particularly limited, and examples thereof 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; and benzotriazole compounds such as 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol and 2-(5-chloro-2-benzotriazolyl)-6-tert-butyl-p-cresol. These may be used alone or in combination of two or more. The ultraviolet absorber contained in the composition for a protective layer can contribute to improving the weather resistance of the protective layer. When the composition for the protective layer contains an ultraviolet absorber, the content of the ultraviolet absorber is not particularly limited, but from the viewpoint of optical properties such as transparency, it is preferably 0.1 to 1.0 mass % in 100 mass % of the composition for the protective layer.

[0119] The composition for the protective layer can be prepared by mixing the various components described above simultaneously or sequentially in any order.

[0120] The protective layer composition is irradiated with light and cured to obtain a protective layer, which is a cured coating layer. The protective layer has scratch resistance. The position of the protective layer is not particularly limited, but is preferably on the cured coating layer (e.g., photochromic layer) from the viewpoint of protecting the cured coating layer (e.g., photochromic layer). From this viewpoint, the protective layer preferably has high hardness. The protective layer is not particularly limited, but preferably has excellent solvent resistance. In the manufacturing process of an optical article, after a layer is formed, a wiping treatment with a solvent is usually carried out to clean the surface of the formed layer, but if the protective layer is damaged in this wiping treatment, it will cause haze or optical defects in the finished lens.

[0121] The thickness of the protective layer is not particularly limited, but is preferably 10 to 50 μm, more preferably 12 to 45 μm, and particularly preferably 15 to 40 μm. If the thickness is equal to or greater than the lower limit of the above range, the durability of the finished lens will be good, and if the thickness is equal to or less than the upper limit of the above range, the transmittance (transparency) of the coating layer will be easily maintained.

[0122] One embodiment of a finished lens manufactured by the manufacturing method for a finished lens according to one aspect of the present disclosure may have a layer structure of "photochromic layer / protective layer." Regarding the layer structure, " / " is used to encompass both a structure in which the layers are in direct contact without any other layer intervening therebetween and a structure in which the layers are provided via one or more other layers. Furthermore, in one embodiment, the optical article may have a layer structure of "photochromic layer / protective layer / other cured coating layer." The other cured coating layer is not particularly limited, and examples thereof include a cured coating layer generally referred to as a hard coat layer. These may be used alone or in combination of two or more. Providing a hard coat layer in addition to the protective layer can further enhance the durability of the optical article. Furthermore, in one embodiment, providing a hard coat layer can also enhance the impact resistance of the optical article. In one embodiment, the other cured coating layer may be in direct contact with the protective layer without any other layer intervening therebetween.

[0123] The thickness of the other cured coating layer is not particularly limited, but is preferably 1 to 10 μm, more preferably 1 to 8 μm, and particularly preferably 1 to 5 μm, from the viewpoint of optical properties such as refractive index, etc. In one embodiment, the other cured coating layer can be a layer thinner than the protective layer.

[0124] In one embodiment, the hard coat layer can be formed by irradiating and / or heating a polymerizable composition for forming a hard coat layer (hereinafter, sometimes simply referred to as a "composition for a hard coat layer"). The hard coat layer is not particularly limited, and examples thereof include an organosilicon-based cured coating layer. An organosilicon-based cured coating layer is generally preferred because it has excellent impact resistance. In addition, when an antireflection layer is further provided as one embodiment, an organosilicon-based cured coating layer is generally preferred because it has excellent adhesion to the antireflection layer.

[0125] The organosilicon-based cured coating layer is a cured coating layer obtained by curing a composition for hard coat layer containing an organosilicon compound. The organosilicon compound is not particularly limited and examples thereof include organosilicon compounds capable of generating silanol groups by polymerization treatment such as γ-glycidoxypropyltrimethoxysilane; organopolysiloxanes such as water-dispersed colloidal silica having reactive groups such as halogen atoms or amino groups that undergo condensation reaction with silanol groups; 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; etc. These may be used alone or in combination of two or more. The hard coat layer composition containing an organosilicon compound may further contain silicon oxide; particles of an inorganic substance such as titanium oxide; etc., as necessary, for adjusting the refractive index, etc. In addition to the above, the hard coat layer composition containing an organosilicon compound may further contain, as necessary, a curing agent such as aluminum acetylacetonate to improve the hardness of the hard coat layer; a surfactant such as a silicone surfactant to control liquid dispersibility and interfacial tension; etc. For details of the polymerizable composition containing an organosilicon compound, known techniques related to organosilicon-based cured coating layers that can function as hard coat layers can be applied. The polymerizable composition containing an organosilicon compound can be cured by promoting a polymerization reaction through light irradiation and / or heat treatment, depending on the types of components contained in the composition.

[0126] The composition for a hard coat layer may or may not contain a solvent. When the composition for a hard coat layer contains a solvent, any solvent can be used in any amount without any particular limitation as long as it does not inhibit the progress of the polymerization reaction of the polymerizable composition.

[0127] When the other cured coating layer is provided on the protective layer, there is no particular limitation, but from the viewpoint of preventing foreign matter from being interposed between the protective layer and the other cured coating layer, it is preferable to subject the surface of the protective layer to a wiping treatment with a solvent. However, if the protective layer has poor solvent resistance, the solvent wiping treatment will damage the protective layer (for example, cause surface roughness), which will cause haze and optical defects in the finished lens including the protective layer. In contrast, the protective layer formed from the above-mentioned protective layer composition exhibits excellent solvent resistance, and therefore can be said to be suitable for providing the other cured coating layer on the protective layer.

[0128] The wiping treatment with a solvent is not particularly limited and can be performed by a known method, for example, wiping the surface of the protective layer with a cloth soaked in the solvent. The solvent is not particularly limited and examples thereof include ketone solvents such as acetone; alcohol solvents such as ethanol and isopropyl alcohol; and the like. These may be used alone or in combination of two or more. In one embodiment, the protective layer preferably has high resistance to ketone solvents that are commonly used as wiping solvents during the production of optical articles.

[0129] ((Other Photocurable Compositions)) The photocurable composition may or may not further contain other photocurable compositions, as necessary, in addition to the above-mentioned composition for primer layer, composition for photochromic layer, and composition for protective layer. The other photocurable compositions are not particularly limited and include, for example, compositions that exhibit antireflection properties after curing, compositions that exhibit antifouling properties, photocurable compositions that exhibit antifogging properties, etc. These may be used alone or in combination of two or more.

[0130] The total thickness of the cured coating layers (excluding the hard coat layer) is not particularly limited, but is preferably 40 to 100 μm, more preferably 43 to 95 μm, and particularly preferably 45 to 90 μm. If the thickness is equal to or greater than the lower limit of the above range, adhesion is easily maintained, and if the thickness is equal to or less than the upper limit of the above range, the transmittance (transparency) of the coating layer is easily maintained.

[0131] <Temperature adjustment process> The temperature adjustment step in the method for manufacturing a plastic lens according to one aspect of the present disclosure is a step of adjusting the ambient temperature to a predetermined temperature before the start of light irradiation, and may or may not include other processes. The temperature adjusting step is a step carried out after the above-mentioned coating step, and may be started before the start of light irradiation of the photocurable composition in the curing step described below.

[0132] The ambient temperature before the start of light irradiation is not particularly limited as long as it is -180 to 5°C, but is preferably -170 to 5°C, more preferably -160 to 5°C, and particularly preferably -150 to 5°C. When the temperature is equal to or higher than the lower limit of the above range, an increase in the lens temperature can be easily suppressed, and when the temperature is equal to or lower than the upper limit of the above range, the coolant can be easily supplied.

[0133] The temperature is adjusted by, for example, introducing at least one of an inert liquid, an inert solid, and an inert gas.

[0134] The inert liquid is not particularly limited, and examples thereof include liquid nitrogen, liquefied argon, liquid helium, etc. These may be used alone or in combination of two or more. Among these, liquid nitrogen is preferred from the viewpoints of availability and economy.

[0135] The inert solid is not particularly limited, and examples thereof include dry ice.

[0136] The inert gas is not particularly limited, and examples thereof include nitrogen gas, argon gas, carbon dioxide gas, helium, etc. These may be used alone or in combination of two or more. Among these, nitrogen gas and carbon dioxide gas are preferred from the viewpoints of availability and economy. The inert gas may be, for example, a cooled inert gas derived from an inert liquid such as cooled nitrogen derived from liquid nitrogen (see Example 5 and FIG. 3 described below); a cooled inert gas derived from an inert solid such as cooled carbon dioxide derived from dry ice; or the like.

[0137] The method for creating an inert gas atmosphere by introducing at least one of an inert liquid, an inert solid, and an inert gas is not particularly limited, and examples thereof include (i) a method in which the pressure inside a furnace is reduced and then at least one of an inert liquid, an inert solid, and an inert gas is introduced to create an inert gas atmosphere; (ii) a method in which at least one of an inert liquid, an inert solid, and an inert gas is introduced into a furnace to push out the air inside the furnace and create an inert gas atmosphere; etc. These methods may be used alone or in combination of two or more. One method for maintaining the inert gas atmosphere is to continuously introduce an inert gas into the furnace while discharging the same amount of inert gas from the furnace as the amount introduced. When the inert gas atmosphere is maintained by this method, the flow rate of the inert gas used to maintain the inert gas atmosphere (hereinafter, sometimes simply referred to as the "amount of inert gas introduced for maintaining the atmosphere"; when the inert gas is nitrogen gas, sometimes simply referred to as the "amount of nitrogen gas introduced for maintaining the atmosphere") is not particularly limited, but is preferably 1 to 200 L / min, more preferably 3 to 100 L / min, and particularly preferably 7 to 50 L / min. The total volume of the inert gas introduced to maintain the inert gas atmosphere is not particularly limited, but is preferably 0.5 to 135 m 3 , more preferably 2 to 70 m 3 , particularly preferably 4.5 to 35 m 3When the concentration is equal to or higher than the lower limit of the above range, it becomes easier to stably supply the inert gas, and when the concentration is equal to or lower than the upper limit of the above range, it becomes harder to replace the inert gas, i.e., it becomes harder for oxygen to be mixed in. The "amount of inert gas introduced" is a value measured by adjusting the needle valve using a small flow sensor (MF-F series manufactured by Horiba Ltd.).

[0138] <Curing process> The curing step in the method for producing a plastic lens according to one embodiment of the present disclosure is a step of curing the applied photocurable composition by light irradiation, and may or may not include other treatments. The curing step is a step carried out after the application step and the temperature adjustment step.

[0139] The light irradiation in the curing step may be continuous or intermittent, with continuous light irradiation being preferred from the viewpoint of productivity.

[0140] The environment during the light irradiation in the curing step is not particularly limited, and may be, for example, an inert gas atmosphere or not. Among these, an inert gas atmosphere is preferable from the viewpoint of the curing efficiency of the photocurable composition. One example of the environment is a furnace under an inert gas atmosphere. The inert gas used to create the inert gas atmosphere is not particularly limited, and examples thereof include nitrogen gas, argon gas, and carbon dioxide gas. These may be used alone or in combination of two or more. Among these, from the viewpoints of economy and ease of availability, nitrogen gas and argon gas are preferred, and nitrogen gas is more preferred.

[0141] The method for creating an inert gas atmosphere is not particularly limited, and examples thereof include a method in which the pressure inside a furnace is reduced and then an inert gas is introduced to create an inert gas atmosphere, a method in which an inert gas is introduced into a furnace and the air inside the furnace is pushed out to create an inert gas atmosphere, etc. These methods may be used alone or in combination of two or more. As one mode of the method for maintaining the inert gas atmosphere, a method can be used in which the inert gas is continuously introduced into the furnace while the same amount of inert gas is discharged from the furnace as that introduced.

[0142] The conditions for light irradiation in the curing step are not particularly limited, and the intensity of light irradiation, the irradiation time, the amount of exposure to light irradiation, etc. can be determined depending on the types and compositions of the various components contained in the photocurable composition.

[0143] The intensity of light irradiation when curing the primer layer composition is not particularly limited, and may be, for example, 104 to 156 mW / cm 2 This can be done. The time for light irradiation when curing the primer layer composition is not particularly limited, and can be, for example, 4 to 6 seconds. The exposure dose of light irradiation during curing of the primer layer composition is not particularly limited, and may be, for example, 415 to 935 mJ / cm 2 2 This can be done.

[0144] The intensity of light irradiation when curing the composition for photochromic layer is not particularly limited, and may be, for example, 104 to 156 mW / cm 2 This can be done. The time for light irradiation when curing the composition for photochromic layer is not particularly limited, and can be, for example, 32 to 48 seconds. The exposure dose of light irradiation during curing of the composition for photochromic layer is not particularly limited, and may be, for example, 3325 to 7450 mJ / cm . 2 This can be done.

[0145] The intensity of light irradiation when curing the composition for the protective layer is not particularly limited, and may be, for example, 104 to 156 mW / cm 2 This can be done. The time for light irradiation when curing the composition for protective layer is not particularly limited, and can be, for example, 12 to 18 seconds. The exposure dose of light irradiation during curing of the protective layer composition is not particularly limited, and may be, for example, 1245 to 2810 mJ / cm 2 This can be done.

[0146] The curing step may or may not include other treatments as necessary in addition to curing the applied photocurable composition by light irradiation. The other treatment form of the curing step is not particularly limited, and examples thereof include annealing (heat treatment) after light irradiation, which can improve the adhesion of each cured coating layer. The conditions for the annealing are not particularly limited, but it is preferable to perform the annealing in a heat treatment furnace at an atmospheric temperature of about 70 to 140°C for 0.5 to 4 hours. [Example]

[0147] The present disclosure will be further described below with reference to examples, but the present disclosure is not limited to the embodiments shown in the examples.

[0148] [Preparation of polymerizable composition for forming photochromic layer] In a plastic container, polyethylene glycol dimethacrylate ((in the above formula (2), n = 14, R = ethylene group, R 1 and R 2 90 parts by mass of methyl group (number average molecular weight 726) and 10 parts by mass of tricyclodecane dimethanol dimethacrylate (molecular weight 332) were mixed to obtain a mixture of polymerizable compounds. The resulting mixture of polymerizable compounds was mixed with a photochromic compound (an indeno-fused naphthopyran compound represented by the following structural formula (6) described in U.S. Pat. No. 5,645,767), a photoradical polymerization initiator (bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, manufactured by IGM Resin BV, Omnirad 819), an antioxidant (ethylene bis(oxyethylene)bis-(3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate)), and a light stabilizer (a mixture of bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate and methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate) and thoroughly stirred. The mixture was then degassed using a rotation-revolution type stirring and degassing device. Photochromic layer composition 1 was thus obtained. The contents of the various components are as follows: 90.0% by mass of the mixture of polymerizable compounds, 5.7% by mass of the photochromic compound, 0.7% by mass of the photoradical polymerization initiator, 2.7% by mass of the antioxidant, and 0.9% by mass of the light stabilizer, based on 100% by mass of the composition 1 for photochromic layer.

[0149] [ka] ···(6)

[0150] [Preparation of polymerizable composition for forming primer layer] A moisture-curing primer polyurethane resin ("Takenate M-605N" manufactured by Mitsui Takeda Chemicals Inc.) and butyl acetate were mixed in a mass ratio of 1:1 and thoroughly stirred under a nitrogen atmosphere until homogeneous, to prepare primer layer-forming polymerizable composition 1. The isocyanate group content of the moisture-curing primer was 2.4 mol% as determined by the amine equivalent method (see Japanese Patent No. 4405833).

[0151] [Preparation of Polymerizable Composition for Forming 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, mixed thoroughly, and stirred for 24 hours at 5° C. 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, stirred thoroughly, and then filtered to prepare composition 1 for hard coat layer.

[0152] [Preparing the oven (UV curing chamber)] A plate-shaped lens base (made of polyoxymethylene, homemade) used to fix the lens substrate was placed in the oven where the curing process was carried out. That is, in the oven where the curing process was carried out, the light source for irradiation, the lens substrate, and the plate-shaped lens base were arranged from top to bottom. The light source for irradiation and the plate-shaped lens base were arranged so that there was a distance of 300 mm between them.

[0153] [Manufacturing plastic lenses with photochromic properties] Example 1 A lens substrate (EYNOA, S-8.00, manufactured by HOYA Corporation, thickness of 1.0 mm at the center and 9.1 mm at the periphery) 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. Then, in an environment of 25°C temperature and 50% relative humidity, a primer layer composition (a coating liquid of polyurethane emulsion) was discharged from the tip of a nozzle, and the lens substrate was rotated with the convex surface (object side surface) facing upward (coating by spin coating). The solvent in the primer layer composition was removed by centrifugal force, and solidification proceeded, forming a primer layer. The formed primer layer had a thickness of 8 μm. Next, the photochromic layer composition 1 was applied onto the primer layer by spin coating using the method described in JP-A-2005-218994. 1 and 2, the lens substrate 20 was fixed to a lens receiving rotation jig 11 placed in a UV curing chamber 100 (temperature 15°C) in which a thermometer 10 (K thermocouple: φ0.5 mm, sheath, JIS C 1602:2015 class 2) was placed. Nitrogen gas 12 (replacement gas, 20°C) was then introduced into the UV curing chamber 100 through an inlet provided at the top of the side of the UV curing chamber 100 at a flow rate of 26 L / min for a total of 28 m 3 While nitrogen gas 14 was being discharged from the UV curing chamber 100 through an outlet provided at the bottom of the UV curing chamber 100, a nitrogen atmosphere with a temperature of -50°C and an oxygen concentration of 500 volume ppm or less was created using nitrogen gas evaporated from 60 g of liquid nitrogen with an evaporation temperature of -196°C stored in a refrigerant tray 13 arranged at the bottom of the UV curing chamber 100. In this nitrogen atmosphere (temperature of -50°C, oxygen concentration of 500 volume ppm or less), the photochromic layer composition 1 applied to the lens substrate 20 was irradiated with light (continuous irradiation, light wavelength: 365 nm, light irradiation intensity: 130 mW / cm) using a UV lamp (metal halide) (not shown). 2 , Light irradiation time: 40 seconds, Light irradiation exposure: 5200 mJ / cm 2 ) and the composition was cured to form a photochromic layer. The surface temperature of the lens after light irradiation was 42°C. The thickness of the photochromic layer formed after photochromic layer formation was 40 μm. After forming the above two layers (primer layer and photochromic layer), heat treatment was carried out for 2 hours at an ambient temperature of 83°C in a heat treatment device (PH series, manufactured by Espec Corporation) to strengthen the adhesion of each cured coating layer. After the heat treatment, to prevent surface scratches, hard coat layer composition 1 was applied to the convex and concave surfaces by dip coating. Then, a heat curing treatment was performed at an ambient temperature of 100°C for 1 hour in a heat treatment device (PH series, manufactured by Espec Corporation), forming a hard coat layer. The thickness of the formed hard coat layer was 3.5 μm. The "thickness" is a value measured using a non-contact film thickness measuring device (FF8 series, manufactured by System Road Co., Ltd.). The "light irradiation intensity" is a value measured using a light meter (UIT-250, manufactured by USHIO Corporation) by lighting a lens base 300 mm away from the center of the light source to the light receiving part (center wavelength 365 mm). The above "light exposure" is the integrated value of the irradiation time (light irradiation intensity (mW / cm)) measured by using a light meter (UIT-250, manufactured by USHIO Co., Ltd.) to illuminate a lens base 300 mm away from the center of the light source to the light receiving part (center wavelength 365 mm). 2 ) × irradiation time (seconds). The "surface temperature of the lens after light irradiation" is the value measured using a radiation thermometer (TMHX-CNE0500 series, manufactured by Japan Sensor Co., Ltd., emissivity 0.95) at the point of the lens substrate 20 closest to the light source (the center of the lens substrate 20) after the UV curing process was completed. The "amount of introduced nitrogen gas" is a value measured by adjusting the needle valve using a small flow sensor (MF-F series manufactured by Horiba, Ltd.). In this way, the finished lens of Example 1 was obtained.

[0154] Example 2 A finished lens of Example 2 was obtained in the same manner as in Example 1, except that, instead of performing heat treatment at an atmospheric temperature of 83°C after forming two layers (primer layer and photochromic layer) in Example 1, heat treatment at an atmospheric temperature of 120°C was performed after forming the two layers.

[0155] Example 3 A finished lens of Example 3 was obtained in the same manner as in Example 1, except that nitrogen gas evaporated from 150 g of liquid nitrogen was used to create a nitrogen atmosphere at a temperature of -100°C, instead of nitrogen gas evaporated from 60 g of liquid nitrogen in Example 1. The surface temperature of the lens after light irradiation was 35°C.

[0156] Example 4 A finished lens of Example 4 was obtained in the same manner as in Example 1, except that instead of using nitrogen gas evaporated from 60 g of liquid nitrogen, which has a vaporization temperature of -196°C, to create a nitrogen atmosphere at a temperature of -50°C, carbon dioxide gas sublimated from 60 g of dry ice, which has a vaporization temperature of -78.5°C, was used to create a carbon dioxide atmosphere at a temperature of -20°C. The surface temperature of the lens after light irradiation was 40°C.

[0157] Example 5 In Example 1, instead of introducing nitrogen gas 12 (for replacement, 20°C) and using nitrogen gas evaporated from 60 g of liquid nitrogen to create a nitrogen atmosphere at a temperature of -50°C, as shown in Figure 3, nitrogen gas 12 (for replacement, 20°C) was introduced into the UV curing chamber 100 through an inlet provided at the top of the side of the UV curing chamber 100, and cooled nitrogen (-50°C) was introduced by the nitrogen gas evaporated from liquid nitrogen at a flow rate of 26 L / min to a total of 28 m 3 A finished lens of Example 5 was obtained in the same manner as in Example 1, except that nitrogen was introduced into the atmosphere and the temperature was 5°C. The surface temperature of the lens after light irradiation was 45°C.

[0158] (Comparative Example 1) 4, a finished lens of Comparative Example 1 was obtained in the same manner as in Example 1, except that liquid nitrogen was not used and a nitrogen atmosphere was used at a temperature of 20°C and an oxygen concentration of 500 volume ppm or less. The surface temperature of the lens after light irradiation was 72°C.

[0159] [Evaluation of finished lenses] The following evaluations were carried out using each of the resulting finished lenses. The evaluation results are shown in Table 1.

[0160] <Adhesion> Evaluation was performed using a cross-cut tape test in accordance with JIS D 0202:2007. Specifically, a cutter knife was used to make slits at approximately 1 mm intervals on the surface of the cured coating layer of each finished lens, forming 100 grids. Cellophane adhesive tape (Cellotape (registered trademark) manufactured by Nichiban Co., Ltd.) was firmly attached to the slits, and then pulled in a 90° direction from the surface. After peeling, the number of grids with the coating layer remaining was counted. The number of remaining squares and the number of squares before peeling were used to evaluate the adhesion according to the following criteria. [Evaluation criteria (number of remaining squares / number of squares before peeling consideration)] A:100 / 100 B: 95 / 100 or more and less than 100 / 100 C: 80 / 100 or more and less than 95 / 100 D: 50 / 100 or more and less than 80 / 100 E: Less than 50 / 100 The adhesiveness can be said to be excellent in the cases of ratings A and B. On the other hand, the adhesiveness cannot be said to be excellent in the cases of ratings C, D and E.

[0161] <Lens deformation> Of the surfaces that had been coated and irradiated with UV light (the convex surface of the lens), a 40 x 40 mm area was measured using a Dual Lens Mapper manufactured by A&R, centered on the part closest to the light source, and the refractive power (Dpt) was detected by the surface reflection method. The absolute value of the difference (amount of change) between the detected refractive power (Dpt) before and after the manufacturing process of the photochromic plastic lens was taken as the degree of lens deformation.

[0162] [Table 1]

[0163] From the results shown in Table 1, it was confirmed that the finished lenses (plastic lenses) of Examples 1 to 5 did not require particularly complicated work or operations, and despite being subjected to light irradiation similar to that for the finished lens (plastic lens) of Comparative Example 1, the degree of lens deformation (thermal deformation) was less than that of the finished lens (plastic lens) of Comparative Example 1. The results shown in Table 1 confirm that the finished lenses (plastic lenses) of Examples 1 to 5 have adhesion equivalent to that of the finished lens (plastic lens) of Comparative Example 1, and it can be assumed that the curing of each photocurable composition has progressed sufficiently.

[0164] Two or more of the various aspects and configurations described herein may be combined in any combination.

[0165] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Industrial Applicability]

[0166] The present disclosure is useful in the technical fields of eyeglasses, goggles, and the like. [Explanation of symbols]

[0167] 10 Thermometer 11 Lens holder rotation jig 12 Nitrogen gas 13 Refrigerant tray 14 Nitrogen gas 20 Lens substrate 100 UV curing chamber

Claims

1. a coating step of coating one surface of a lens substrate with a photocurable composition; a curing step of curing the photocurable composition by light irradiation; and a temperature adjustment step of adjusting the ambient temperature to −180 to 5° C. before starting the light irradiation.

2. The method for producing a plastic lens according to claim 1 , wherein the temperature is adjusted by introducing at least one selected from the group consisting of an inert liquid, an inert solid, and an inert gas in the temperature adjustment step.

3. The method for producing a plastic lens according to claim 2, wherein the inert gas is at least one selected from the group consisting of nitrogen gas, argon gas, and carbon dioxide gas.

4. 3. The method for manufacturing a plastic lens according to claim 1, wherein the one surface is a convex surface and the other surface is a concave surface.

5. 3. The method for producing a plastic lens according to claim 1, wherein the photocurable composition is at least one selected from the group consisting of a polymerizable composition for forming a primer layer, a polymerizable composition for forming a photochromic layer, and a polymerizable composition for forming a protective layer.

6. The method for manufacturing a plastic lens according to claim 1 or 2, wherein the lens substrate has a central portion having a thickness of less than 2 mm and a peripheral portion having a thickness greater than that of the central portion.

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