CURABLE PHOTOCHROMIC COMPOSITION INCLUDING A SEGMENTED POLYMER

Abstract

The present invention relates to a curable photochromic composition comprising (a) a photochromic compound; (b) a segmented polymer having active hydrogen groups, at least a first segment, and at least a second segment, wherein (i) each first segment independently includes a fluorinated polymer segment, and (ii) each second segment independently includes a segment selected from a polycarbonate segment, a polyester segment, a polyether segment, a polyurethane segment, and a copolymer segment thereof; and (c) a curing agent having reactive functional groups that are reactive with the active hydrogen groups of the segmented polymer, wherein the curing agent includes at least one polyisocyanate, polyisothiocyanate, or aminoplast. Photochromic articles and films, including multilayer articles, comprising the curable photochromic composition are also provided.

Description

CURABLE PHOTOCHROMIC COMPOSITION INCLUDING A SEGMENTED FIELD POLYMER The present invention relates to curable photochromic compositions, comprising a photochromic compound, a segmented polymer including at least a first segment and at least a second segment, and a curing agent. Photochromic articles prepared from such compositions are also provided. BACKGROUND In response to specific wavelengths of electromagnetic radiation (or actinic radiation), photochromic compounds, such as indenofused naphthopyrans, typically undergo a transformation from one form or state to another, each form having a characteristic or distinguishable absorption spectrum associated with it. Typically, upon exposure to actinic radiation, many photochromic compounds transform from a closed form, corresponding to an inactivated (or bleached, for example, substantially colorless) state of the photochromic compound, to an open form, corresponding to an activated (or colored) state of the photochromic compound. In the absence of exposure to actinic radiation, such photochromic compounds transform reversibly from the activated (or colored) state to the inactivated (or bleached) state.Compositions and articles, such as optical lenses, containing photochromic compounds or having photochromic compounds applied to them (e.g., in the form of a photochromic coating composition) normally exhibit colorless (e.g., transparent) and colored states that correspond to the colorless and colored states of the photochromic compounds contained therein or applied to them. Photochromic compounds can be used in curable compositions to form, for example, cured layers, such as cured films or sheets that are photochromic. With cured photochromic films, such as cured photochromic coatings, it is generally desirable that they provide a combination of hardness and photochromic performance. In general, the kinetics associated with the reversible transformation of a photochromic compound between a closed (inactivated / colorless) form and an open (activated / colored) form are faster in a soft matrix but slower in a hard matrix (of the cured film in which the photochromic compound resides). Cured photochromic films with a soft matrix typically have reduced hardness, while those with a hard matrix typically have increased hardness.Prepolymer resins often show improvements in hardness and dye kinetics, but are more sensitive to dye fatigue or dye degradation. It would be desirable to develop curable photochromic compositions that provide cured photochromic layers having acceptable hardness, improved kinetics, and improved dye fatigue. SUMMARY The present invention relates to a curable photochromic composition comprising: (a) a photochromic compound; (b) a segmented polymer comprising active hydrogen groups, at least a first segment, and at least a second segment, wherein: (i) each first segment independently comprises a fluorinated polymer segment, and (ii) each second segment independently comprises a segment selected from the group consisting of a polycarbonate segment, a polyester segment, a polyether segment, a polyurethane segment, and a copolymer segment thereof; and (c) a curing agent comprising reactive functional groups that are reactive with the active hydrogen groups of the segmented polymer, wherein the curing agent comprises at least one of a polyisocyanate, a polyisothiocyanate, or an aminoplast. The present invention also provides photochromic articles and films, including multilayer articles comprising the curable photochromic composition. The features that characterize the present invention are specifically set forth in the attached claims, which form part of this disclosure. These and other features of the invention, its operational advantages, and the specific objects obtained by its use will be better understood from the following detailed description, which illustrates and describes non-limiting embodiments of the invention. DETAILED DESCRIPTION As used herein, the articles un, una and el / la include plural referents unless otherwise stated and are unequivocally limited to a single referent. Unless otherwise stated, all intervals or ratios described herein should be understood to encompass each and every subinterval or subratio included therein. For example, a range or ratio of 1 to 10 should be considered to include each and every subrange between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subintervals or MA / IZ / ¿U¿¿ / UO9¿OU subrelations that begin with a minimum value of 1 or more and end with a maximum value of 10 or less, such as but not limited to 6.1, 3.5 to 7.8, and 5.5 to 10. Except in operational examples, or where otherwise indicated, all numbers expressing quantities of components, reaction conditions, etc. used in the descriptive memorandum and the claims shall be understood to be modified in all cases by the term approximately. As used herein, "at least one of" is synonymous with "one or more of," whether the items are listed conjunctively or disjunctively. For example, the phrases "at least one of A, B, and C" and "at least one of A, B, or C" each mean any one of A, B, or C, or any combination of two or more of A, B, or C. For example, A alone; or B alone; or C alone; or A and B; or A and C; or B and C; or all of A, B, and C. As used herein, "selected from" is synonymous with "chosen from," whether the items are listed conjunctively or disjunctively. Furthermore, the phrases "selected from A, B, and C" and "selected from A, B, or C" each mean any one of A, B, or C, or any combination of two or more of A, B, or C. For example, A alone; or B alone; or C alone; or A and B; or A and C; or B and C; or all of A, B, and C. As used herein, the molecular weight values ​​of polymers, such as weight average molecular weights (Mw) and number average molecular weights (Mn), are determined by gel permeation chromatography using appropriate standards, such as polystyrene standards. As used herein, the polydispersity index (PDI) values ​​represent a ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polymer (i.e., Mw / Mn). As used herein, the term polymer means homopolymers (e.g., prepared from a single monomer species), copolymers (e.g., prepared from at least two monomer species), and graft polymers. As used herein, the term (meth)acrylate and similar terms, such as (meth)acrylic acid ester, means methacrylates and / or acrylates. As used herein, the term (meth)acrylic acid means methacrylic acid and / or acrylic acid. As used herein, the term photochromic and similar terms, such as photochromic compound, means having an absorption spectrum for at least visible radiation that varies in response to the absorption of at least actinic radiation. Furthermore, as used herein, the term photochromic material means any substance adapted to exhibit photochromic properties (such as adapted to have an absorption spectrum for at least visible radiation that varies in response to the absorption of at least actinic radiation) and that includes at least one photochromic compound. As used herein, the term actinic radiation means electromagnetic radiation that can cause a response in a material, such as, but not limited to, transforming a photochromic material from one form or state to another, as will be discussed in more detail herein. As used herein, the term photochromic material includes thermally reversible photochromic materials and compounds and thermally non-thermally reversible photochromic materials and compounds. The term thermally reversible photochromic compounds / materials as used herein means compounds / materials that can be converted from a first state, e.g., a clear state, to a second state, e.g., a colored state, in response to actinic radiation, and back to the first state in response to thermal energy.The term thermally non-reversible photochromic compounds / materials as used herein means compounds / materials that can be converted from a first state, e.g. a clear state, to a second state, e.g. a colored state, in response to actinic radiation, and returning to the first state in response to actinic radiation of substantially the same wavelength(s) as the absorption(s) of the colored state. As used herein to modify the term "state," the terms "first" and "second" are not intended to refer to any particular order or chronology, but rather to two different conditions or properties. For non-limiting illustrative purposes, the first and second states of a photochromic compound may differ with respect to at least one optical property, such as, but not limited to, the absorption of visible and / or UV radiation. Thus, the photochromic compounds of the present invention may have a different absorption spectrum in each of the first and second states. For example, without limitation herein, a photochromic compound of the present invention may be transparent in the first state and colored in the second state. Alternatively, a photochromic compound of the present invention may have a first color in the first state and a second color in the second state. As used herein, the term "optical" means pertaining to or associated with light and / or vision. For example, according to various non-limiting embodiments disclosed herein, the optical article, element, or device may be selected from ophthalmic articles, elements, and devices, display articles, elements, and devices, windows, mirrors, and active and passive liquid crystal cell articles, elements, and devices. As used herein, the term ophthalmic means pertaining to or associated with the eye and vision. Non-limiting examples of ophthalmic articles or items include corrective and non-corrective lenses, including single-vision or multifocal lenses, which may be segmented or non-segmented multifocal lenses (such as, but not limited to, bifocal lenses, trifocal lenses, and progressive lenses), as well as other items used to correct, protect, or enhance (cosmetically or otherwise) vision, including, without limitation, contact lenses, intraocular lenses, magnifying lenses, and protective lenses or visors. As used herein, the term display means the visible or machine-readable representation of information in words, numbers, symbols, designs, or drawings. Non-limiting examples of display elements include screens, monitors, and security features such as security markings. As used herein, the term "window" means an opening adapted to permit the transmission of radiation through it. Non-limiting examples of windows include transparencies for automobiles and aircraft, windshields, filters, blinds, and optical switches. As used herein, the term mirror means a surface that specularly reflects a large fraction of the incident light. As used herein, the term liquid crystal cell refers to a structure containing an orderable liquid crystal material. A non-limiting example of a liquid crystal cell element is a liquid crystal display. As used herein, spatial or directional terms such as left, right, inside, outside, up, down, and the like refer to various orientations of the invention as may be further described herein, such as articles and multilayer articles of the present invention. It should be understood, however, that the invention may assume various orientations alternative to those described herein, and therefore such terms should not be considered limiting. As used herein, the terms formed on, deposited on, provided on, applied on, residing on, or positioned on mean formed, deposited, provided, applied, residing, or placed on, but not necessarily in direct contact with (or adjacent to) the underlying element or the surface of the underlying element. For example, a layer placed on a substrate does not preclude the presence of one or more layers, coatings, or films of the same or different composition located between the placed or formed layer and the substrate. All documents, such as, but not limited to, issued patents and patent applications, referenced herein, unless otherwise stated, shall be deemed to be incorporated by reference in their entirety. As used herein, references to linear or branched groups, such as linear or branched alkyl, are understood to include a methylene group or a methyl group; groups that are linear, such as linear C2-C20 alkyl groups; and groups that are appropriately branched, such as branched C3-C20 alkyl groups. As used herein, references to an optionally substituted group mean a group, including but not limited to, an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, and / or a heteroaryl group, wherein at least one hydrogen atom thereof has been optionally replaced or substituted with a group other than hydrogen, such as, but not limited to, halo groups (for example, F, Cl, I, and Br), hydroxyl groups, ether groups, thiol groups, thioether groups, carboxylic acid groups, carboxylic acid ester groups, phosphoric acid groups, phosphoric acid ester groups, sulfonic acid groups, sulfonic acid ester groups, nitro groups, cyano groups, alkyl groups (including aralkyl groups); alkenyl groups; alkynyl groups; haloalkyl groups; perhaloalkyl groups; heterocycloalkyl groups;aryl groups (including alkaryl groups, including hydroxyl-substituted aryl such as phenol, and including polycondensed ring aryl); heteroaryl groups (including polycondensed ring heteroaryl groups); or amine groups, such as -N(Rn')(R12') where Rn' and R12' are each independently selected from hydrogen, linear or branched C1-C20 alkyl, C3-C12 cycloalkyl, C3-C12 heterocycloalkyl, aryl or heteroaryl. As used herein, references to halo-substituted and related terms (such as, but not limited to, haloalkyl groups, haloalkenyl groups, haloalkynyl groups, haloaryl groups, and halo-heteroaryl groups) mean a group in which at least one and up to and including all of the available hydrogen groups thereof is substituted with a halo group. The term halo-substituted includes perhalo-substituted. As used herein, the term perhalo-substituted group and related terms (such as, but not limited to, perhaloalkyl groups, perhaloalkenyl groups, perhaloalkynyl groups, perhaloaryl groups, and perhalo-heteroaryl groups) means a group in which all of the available hydrogen groups thereof are substituted with a halo group. For example, perhalomethyl is -CX3; Perhalophenyl is -CeXs, where X represents one or more halo groups, such as, but not limited to, F. Representative alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, terebutyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, and decyl. Representative alkenyl groups include, but are not limited to, vinyl, allyl, and propenyl. Representative alkynyl groups include, but are not limited to, ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, and 2-butynyl. Representative cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl substituents. Representative heterocycloalkyl groups include, but are not limited to, imidazolyl, tetrahydrofuranyl, tetrahydropyranyl, and piperidinyl. Representative aryl groups include, but are not limited to, phenyl, naphthyl, anthracynyl, and trypticenyl. Representative heteroaryl groups include, but are not limited to, furanyl, pyranyl, pyridinyl, isoquinoline, and pyrimidinyl.Representative aralkyl groups include, but are not limited to, benzyl and phenethyl. The term alkyl, as used herein, means linear or branched alkyl, such as, but not limited to, linear or branched C1-C25 alkyl, linear or branched C1-C10 alkyl, or linear or branched C2-C10 alkyl. Examples of alkyl groups from which the various alkyl groups of the present invention may be selected include, but are not limited to, those mentioned above. The term cycloalkyl, as used herein, means groups that are appropriately cyclic, such as, but not limited to, C3-C2 cycloalkyl groups (including, but not limited to, cyclic C5-C7 alkyl). Examples of cycloalkyl groups include those cited above in this document. The term cycloalkyl, as used herein, also includes: bridged polycycloalkyl groups (or bridged polycyclic alkyl groups), such as, but not limited to, bicyclo[2.2.1]heptyl (or norbornyl) and bicyclo[2.2.2]octyl; and fused polycycloalkyl groups (or fused polycyclic alkyl groups), such as, but not limited to, octahydro-1H-indenyl and decahydronaphthalenyl. The term heterocycloalkyl as used herein means groups that are appropriately cyclic, such as, but not limited to, C3-C12 heterocycloalkyl groups or C5-C7 heterocycloalkyl groups, and that have at least one heteroatom in the cyclic ring, such as, but not limited to, O, S, N, P, and combinations thereof. Examples of heterocycloalkyl groups include, but are not limited to, those mentioned above herein. The term heterocycloalkyl as used herein also includes: polycyclic bridged-ring heterocycloalkyl groups, such as, but not limited to, 7oxabicyclo[2.2.1]heptanyl; and polycyclic fused-ring heterocycloalkyl groups, such as, but not limited to, octahydrocyclopenta[b]pyranyl, and octahydro-1H16 isochromenyl. The term heteroaryl, as used herein, includes, but is not limited to, C5-C18 heteroaryl, such as, but not limited to, C5-C10 heteroaryl (including polycyclic fused-ring heteroaryl groups), and means an aryl group having at least one heteroatom on the aromatic ring, or on at least one aromatic ring in the case of a polycyclic fused-ring heteroaryl group. Examples of heteroaryl groups include, but are not limited to, those mentioned above herein. The term aralkyl, as used herein, includes, but is not limited to, C6-C24 aralkyl, such as, but not limited to, CgC10 aralkyl, and means an aryl group substituted with an alkyl group. Examples of aralkyl groups include, but are not limited to, those mentioned above herein.As mentioned above, the photochromic curable compositions of the present invention include a segmented polymer (b) having active hydrogen groups. The segmented polymer (b) includes (i) at least a first segment; and (ii) at least a second segment. Either or both of (i) at least a first segment and (ii) at least a second segment may comprise active hydrogen groups as discussed in detail below. Each of the at least one first segment (i) independently comprises a fluorinated polymer segment. Suitable examples of fluorinated polymers from which the fluorinated polymer segment is derived may include, but are not limited to, alternating fluoroethylene-alkyl vinyl ether copolymers (such as those described in U.S. Patent No. 4,345,057) available from Asahi Glass Company under the name LUMIFLON; and commercially available fluoroaliphatic polymer esters from 3M of St. Paul, Minnesota under the name FLUORAD. The fluorinated polymer segment (i) may include active hydrogen groups such as any of the active hydrogen groups mentioned herein below, e.g., hydroxyl groups. In general, the first segment (i) is present in the segmented polymer (b) in an amount from 5 percent by weight to 70 percent by weight, such as from 5 percent by weight to 60 percent by weight, such as from 8 percent by weight to 55 percent by weight, based on the total weight of the segment polymer. Furthermore, the first segment (i) may comprise from 2 percent by weight to 40 percent by weight of the photochromic curable composition, such as from 2 percent by weight to 30 percent by weight, based on the weight of total solids present in the photochromic curable composition. The segmented polymer (b) of the photochromic curable compositions of the present invention further includes at least a second segment (ii), wherein each second segment independently includes at least one of a polycarbonate segment, a polyester segment, a polyether segment, a polyurethane segment, combinations of two or more of the same, or copolymers of two or more of the same. The at least one second segment (ii) may terminate with a group derived from (i.e., a group that is the residue of) a compound containing active hydrogen. Suitable compounds containing active hydrogen include termination agents recognized in the art (such as one or more of the capping agents described later herein with respect to the capped polyisocyanate curing agent). Each polycarbonate segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For non-limiting illustrative purposes, each polycarbonate segment can be prepared independently from the reaction of a polyol, such as a diol, with a carbonyl dihalide, such as carbonyl dichloride, with elimination of the resulting halide acid, such as HCl. For further non-limiting illustrative purposes, each polycarbonate segment can be prepared independently from a transesterification reaction of a polyol, such as a diol, and a dihydrocarbyl carbonate, such as diphenyl carbonate, with elimination of the resulting hydroxyl functional hydrocarbyl, such as phenol. Examples of polyols having at least two hydroxyl groups, from which each polycarbonate segment can be prepared independently, include, but are not limited to, glycerin, trimethylolpropane, trimethylolethane, trishydroxyethylisocyanurate, pentaerythritol, ethylene glycol, propylene glycol, trimethylene glycol, 1,3-, 1,2- and 1,4-butanediols, pentanediols (such as, but not limited to, 1,5-pentanediol), heptanediol, hexanediol, octanediol, 4,4'-(propane-2,2-diyl)dicyclohexanol, 4,4'-methylenedicyclohexanol, neopentyl glycol, 2,2,3-trimethylpentane-1,3-diol, 1,4-dimethylolcyclohexane, 2,2,4-trimethylpentanediol, 4,4'-(propane-2,2-diyl)diphenol, 4,4'methylenediphenol and similar polyols. Each polycarbonate segment of every second segment may be independently free of active hydrogen functionality, or include one or more active hydrogen functional groups, each independently selected from hydroxyl, thiol, primary amine, or secondary amine. Active hydrogen functionality may be independently introduced into each polycarbonate segment during or after its formation, according to recognized methods in the art. In some embodiments, at least some of the polycarbonate segments have hydroxyl functionality. The polycarbonate segments having hydroxyl functionality may, in some embodiments, be prepared from polycarbonate polyols, such as polycarbonate diols.Polycarbonate polyols, such as polycarbonate diols, can be selected, with some additional embodiments, from commercially available polycarbonate polyols, such as, but not limited to, ETERNACOLL polycarbonate diols from UBE Industries. Each polycarbonate segment of each second segment can have any suitable molecular weight. For example, each polycarbonate segment of each second segment can independently have a Mn value less than 20,000, such as less than 15,000. Each polycarbonate segment of each second segment can have a Mn value greater than 3,000, such as 3,000 to 20,000, or such as 3,000 to 15,000. Each polyester segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For non-limiting illustrative purposes, each polyester segment can be prepared independently by reacting materials with carboxylic acid functionality (and / or cyclic anhydrides thereof, and / or esters thereof) having carboxylic acid functionalities (or effective carboxylic acid functionalities, such as in the case of cyclic anhydrides and esters of carboxylic acids) of at least 2, and polyols having hydroxyl functionalities of at least 2. The molar equivalent ratio of carboxylic acid groups to hydroxyl groups of the reactants is selected so that the resulting polyester segment has hydroxyl and / or carboxylic acid functionality and a desired molecular weight. Examples of useful multifunctional carboxylic acids for preparing each polyester segment include, but are not limited to, italic acid, tetrahydrophthalic acid, hexahydrophthalic acid, endobicyclo-2,2,1,5-heptyne-2,3-dicarboxylic acid, tetrachlorophthalic acid, cyclohexanedioic acid, succinic acid, isophthalic acid, terephthalic acid, azelaic acid, maleic acid, trimesic acid, 3,6-dichlorophthalic acid, adipic acid, sebacic acid, and similar multifunctional carboxylic acids (including optionally appropriate cyclic anhydrides thereof and / or esters thereof). Examples of polyols that can be used to prepare each polyester segment of the second segment include, but are not limited to, the examples of polyols cited earlier in this document. Each polyester segment of every second segment may be independently free of active hydrogen functionality, or include one or more active hydrogen functional groups, each independently selected from hydroxyl, thiol, primary amine, or secondary amine. Active hydrogen functionality may be independently introduced into each polyester segment during its formation, or after its formation, according to recognized methods in the art. Each polyester segment of each second segment can have any suitable molecular weight. For example, each polyester segment of each second segment can independently have a Mn value less than 20,000, such as less than 15,000. Each polyester segment of each second segment can have a Mn value greater than 3,000, such as 3,000 to 20,000, or such as 3,000 to 15,000. Each polyether segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, each polyether segment can be prepared independently from the reaction of polyols having two or more hydroxyl groups and polyepoxides having two or more epoxide (or oxirane) groups, reacted in proportions such that the resulting polyether has hydroxyl and / or oxirane functionality. The polyols and polyepoxides used in the preparation of the polyether segment can be selected, for example, from aliphatic, cycloaliphatic, or aromatic polyols or polyepoxides, or mixtures thereof. Specific examples of polyols include those cited earlier in this document. Polyepoxides useful for preparing the polyether segments can include those resulting from the reaction of a polyol and epichlorohydrin.One or more of the polyols cited above in this document may be reacted with epichlorohydrin to give a polyepoxide. For illustrative purposes only, each polyether segment may be prepared independently from: 4,4'-(propane-2,2-diyl)diphenol and the diglycidyl ether of 4,4'-(propane-2,2-diyl)diphenol; or 4,4'-(propane-2,2-diyl)dicylcohexanol and the diglycidyl ether of 4,4'-(propane-2,2-diyl)dicylcohexanol. Each polyether segment of every second segment may be independently free of active hydrogen functionality, or include one or more active hydrogen functional groups, each independently selected from hydroxyl, thiol, primary amine, or secondary amine. Active hydrogen functionality may be independently introduced into each polyether segment during its formation, or after its formation, according to recognized methods in the art. Each polyether segment of each second segment can have any suitable molecular weight. For example, each polyether segment of each second segment can independently have an Mn less than 20,000, such as less than 15,000. Each polyether segment of each second segment can have an Mn greater than 3,000, such as from 3,000 to 20,000, or from 3,000 to 15,000. Each polyurethane segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, each polyurethane segment can be prepared independently from the reaction of a polyisocyanate having at least two isocyanate groups with a polyol having at least two hydroxyl groups, with an appropriate molar excess of hydroxyl groups, to form a polyurethane with hydroxyl functionality having at least two hydroxyl groups; or with an appropriate molar excess of isocyanate groups to form a polyurethane having at least two isocyanate groups. Examples of polyisocyanates useful in the preparation of polyurethane segments include, but are not limited to, aliphatic, aromatic, cycloaliphatic, and heterocyclic polyisocyanates, and mixtures of such polyisocyanates. Additional examples of polyisocyanates useful in the preparation of polyurethane segments include, but are not limited to, toluene-2,4-diisocyanate; toluene-2,6-diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenyl methane-2,4'-diisocyanate; para-phenylene diisocyanate; biphenyl diisocyanate; 3,3'-dimethyl-4,4'-diphenylene diisocyanate; tetramethylene-1,4-diisocyanate; hexamethylene-1,6-diisocyanate; 2,2,4-trimethylhexane-1,6-diisocyanate; 2,4,4-trimethylhexane-1,6-diisocyanate; lysine methyl ester diisocyanate; bis(ethyl isocyanate) fumarate; isophorone diisocyanate; ethylene diisocyanate; dodecane-1,12-diisocyanate; cyclobutane-1,3-diisocyanate; cyclohexane-1,3-diisocyanate; cyclohexane-1,4-diisocyanate; methyl cyclohexyl diisocyanate; hexahydrotoluene-2,4-diisocyanate; hexahydrotoluene-2,6-diisocyanate; hexahydrophenylene-1,3-diisocyanate; hexahydrophenylene-1,4-diisocyanate; perhydrodiphenylmethane-2,4'-diisocyanate; perhydrodiphenylmethane-4,4'-diisocyanate;norbornane diisocyanate; and mixtures thereof.; Examples of polyols that have at least two hydroxyl groups, from which they can be prepared MA / IZ / ¿U¿¿ / UOO¿OU The polyurethane segments of the second segment include, but are not limited to, the polyols mentioned above in this document. Each polyurethane segment of every second segment may be independently free of active hydrogen functionality, or include one or more active hydrogen functional groups, each independently selected from hydroxyl, thiol, primary amine, or secondary amine. Active hydrogen functionality may be independently introduced into each polyurethane segment during or after its formation, according to recognized methods in the art. Each polyurethane segment of each second segment can have any suitable molecular weight. For example, each polyurethane segment of each second segment can independently have a Mn value less than 20,000, such as less than 15,000. Each polyurethane segment of each second segment can have a Mn value greater than 3,000, such as 3,000 to 20,000, or such as 3,000 to 15,000. Each second segment of the segmented polymers of the curable compositions of the present invention may independently include at least one of a polycarbonate segment, a polycarbonate-polyester segment, a polycarbonate-polyurethane segment, a polyether-polyurethane segment, or a polycarbonate-polyurethane-polyurethane segment. Each second segment may comprise extended polyol chain combinations with difunctional linkers, for example, but not limited to, dicarboxylic acids to give ester linkages, bischloroformates to give carbonate linkages, diisocyanates to give urethane linkages, diols to give ether linkages, or combinations of ester and urethane linkages, such that the second segment has a final Mn less than 20,000 and greater than 3,000, such as from 3,000 to 15,000. Each polycarbonate-polyester segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, and not as a limitation, each polycarbonate-polyester segment can be prepared independently according to the description provided above herein regarding the preparation of a polyester segment, wherein at least some of the polyols are polycarbonate polyols. The polycarbonate polyols can be prepared according to the description provided above herein regarding the preparation of a polycarbonate segment, with the molar ratios of the reagents adjusted so that the resulting polycarbonate has hydroxyl functionality and is, correspondingly, a polycarbonate polyol. Each polycarbonate-polyurethane segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, and not as a limitation, each polycarbonate-polyurethane segment can be prepared independently according to the description provided earlier herein regarding the preparation of a polyurethane segment, wherein at least some of the polyols are polycarbonate polyols. The polycarbonate polyols can be prepared according to the description provided earlier herein regarding the preparation of a polycarbonate segment, with the molar ratios of the reagents adjusted so that the resulting polycarbonate has hydroxyl functionality and is, correspondingly, a polycarbonate polyol. Each polyether-polyurethane segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, and not as a limitation, each polyether-polyurethane segment can be prepared independently according to the description provided earlier herein regarding the preparation of a polyurethane segment, wherein at least some of the polyols are polyether polyols. The polyether polyols can be prepared according to the description provided earlier herein regarding the preparation of a polyether segment, with the molar ratios of the reagents adjusted so that the resulting polyether has hydroxyl functionality and is correspondingly a polyether polyol. Each polycarbonate-polyurethane segment of every second segment of the segmented polymer can be prepared independently according to recognized methods in the art. For illustrative purposes only, and not as a limitation, each polycarbonate-polyurethane segment can be prepared independently according to the description provided earlier herein regarding the preparation of a polyurethane segment, wherein at least some of the polyols are polycarbonate-polyester polyols. The polycarbonate-polyester polyols can be prepared according to the description provided earlier herein, wherein the molar ratio of the reactants is adjusted so that the resulting polymer has hydroxyl functionality and, correspondingly, is a polycarbonate-polyester polyol. In general, the second segment (ii) is present in the segmented polymer (b) in an amount from 30 wt% to 95 wt%, such as from 40 wt% to 95 wt%, or from 45 wt% to 92 wt%, based on the total weight of the segment polymer. Furthermore, the second segment (ii) comprises from 15 wt% to 70 wt%, such as from 20 wt% to 60 wt%, or from 22 wt% to 55 wt%, of the photochromic curable composition, based on the weight of total solids present in the photochromic curable composition.The total weight of solids of the curable photochromic composition does not include the weight of any volatile components, such as solvents, and includes the weight of the non-volatile components, including the photochromic compounds; the segmented polymer; the curing agent; and any optional non-volatile additives, such as, but not limited to, ultraviolet light stabilizers, thermal stabilizers, etc., as further described herein. As mentioned above, the segmented polymer(s) (b) of the photochromic curable compositions of the present invention include active hydrogen groups. For example, at least one first segment and / or at least one second segment of each segmented polymer may independently include one or more active hydrogen groups. The weight equivalent of active hydrogen of the segmented polymer (b) in general, is selected so that a cured article, such as a cured coating layer or a cured polymeric film (or sheet), prepared from the photochromic curable compositions of the present invention, has desirable properties, including, but not limited to, a desirable level of hardness, or a desirable photochromic performance (such as reduced attenuation half-life (T1 / 2) values). The segmented polymer (b) may have an active hydrogen equivalent weight of less than or equal to 20,000 grams per equivalent (g / eq), such as less than 18,000 g / eq, or less than 15,000 g / eq. The segmented polymer (b) may have an active hydrogen equivalent weight of from 1,000 to 15,000 g / eq, or from 1,000 to 13,000 g / eq, or from 1,000 to 10,000 g / eq. Each active hydrogen group of the segmented polymer (b) is independently selected from hydroxyl (-OH), thiol (-SH), primary amine (-NH2), or secondary amine (-NHR' or cyclic amine). The R' group of each secondary amino group (-NHR') may be selected from any suitable organic group, such as a linear or branched C1-C20 alkyl group, a cycloalkyl group, or an aryl group, including the classes and examples thereof mentioned earlier herein. Cyclic amines from which the secondary amine group may be selected include, but are not limited to, those represented by the following formula (A): (Y)pN-H (A) With reference to Formula (A), subscript p is at least 3, such as 3, 4, 5, 6, or 7; and Y independently for each p is selected from -CH2-, -CH(R''), or -C(R'')2-, provided that a Y includes a single bond to the segmented polymer. Each R' may be selected from any suitable organic group, such as a linear or branched C1-C20 alkyl group, a cycloalkyl group, or an aryl group, including the classes and examples thereof mentioned earlier herein. Examples of cyclic amino groups from which each secondary amino group of the segmented polymer may be independently selected include, but are not limited to, azetidinyl, pyrrolidinyl, piperidinyl, azepanyl, and azoconyl. Each active hydrogen group of the segmented polymer can be a hydroxyl group. The segmented polymer (b) can have a hydroxyl equivalent weight of less than or equal to 8,000 grams per equivalent (g / eq). For example, the segmented polymer can have a hydroxyl equivalent weight of from 1,000 to 15,000 g / eq, or from 1,200 to 13,000 g / eq, or from 1,500 to 11,000 g / eq. The hydroxyl equivalent weight of the segmented polymer can be calculated by dividing the mass of the resin solids by the difference between the sum of the moles of alcohol in the alcohol-containing components and the sum of the moles of isocyanate in the isocyanate-containing components. Each first segment (i) and each second segment (ii) of the segmented polymer (b) can be formed separately. Subsequently, the first segment(s) and the second segment(s) are combined (as if reacting together, resulting in the formation of covalent bond(s) between them) to form the segmented polymer of the photochromic curable compositions of the present invention. Alternatively, each first segment can be formed initially, and subsequently, each second segment can be formed by polymerization from (or away from) the backbone of the first segment. With the segmented polymers of the photochromic curable compositions of the present invention, at least a first segment and at least a second segment are covalently linked together by a linkage group selected from the group consisting of a carboxylic acid ester linkage group (-C(O)O-), a thioester linkage group (-C(O)-S-), an amide linkage group (-C(O)-N(R1)MA / IZ / ¿U¿¿ / UOO¿OU), a urethane linkage group (-N(H)-C(O)-O-), a thiourethane linkage group (-N(H)-C(O)-S-), a urea linkage group (-N(R1)-C(O)-N(R1)-), a thiourea linkage group (N(R1)-C(S)-N(R1)-), a carbonate linkage group (-OC(O)0—), an ether-bonding group (-O-), and a thioether-bonding group (-S-).Each R1 group of the bonding groups mentioned above may be independently selected from hydrogen or any suitable organic group, such as a linear or branched C1-C20 alkyl group, a cycloalkyl group, or an aryl group, including the classes and examples thereof mentioned above in this document. In general, each second segment is covalently bonded to at least one first segment. The segmented polymers of the photochromic curable compositions of the present invention are non-gelled. Furthermore, at least one first segment and at least one second segment of the segmented polymer (b) may be covalently bonded to each other by a multifunctional linkage group, such as a difunctional linkage group. Each functional group of the multifunctional linkage group may be selected from a precursor of a linkage group described above.For the purposes of non-limiting illustration, an isocyanate functional group (-NCO) is a precursor to a binding group, such as but not limited to a urethane binding group (-N(H)-C(O)-O), a thiourethane binding group (-N(H)-C(O)-S-), or a urea binding group (-N(H)-C(O)-N(R1)-), where R1 is selected from hydrogen and any suitable organic group, as described above herein. For non-limiting purposes, a difunctional linkage group (such as, but not limited to, a diisocyanate, dicarboxylic acid, dicarboxylic acid ester, or dihaloformate functional linkage group) and a second hydrogen-active functional segment (such as a second hydroxyl functional segment) can be reacted together, such that the second segment includes at least one functional group from the difunctional linkage group. For further non-limiting purposes, a diisocyanate functional linkage group and a second dihydroxyl functional segment (or precursor of the second segment) can be reacted together with an isocyanate-to-hydroxyl functional group ratio of 1.1:1 to 3:1, or 1.5:1 to 2:1. The resulting second isocyanate-functionalized segment can then be reacted together with a first hydrogen-active functionalized segment to form a segmented polymer according to the present invention.For purposes including, but not limited to, controlling molecular weight and / or crosslinking, prior to reaction with the first active hydrogen functional segment, at least a portion (e.g., 1% to 60%, or 30% to 50%) of the isocyanate groups of the second isocyanate-functionalized segment may be capped (or blocked) with a capping agent (such as one or more of the capping agents cited later herein with respect to the capped polyisocyanate curing agent). Alternatively, prior to (and / or during) reaction with the second dihydroxylated functional segment, at least a portion (e.g., 1% to 50%, or 30% to 60%) of the isocyanate groups of the functional diisocyanate linkage group may be capped with a capping agent. Without intending to be limited to any particular theory, it is believed that a cured coating layer or film prepared from the curable photochromic compositions of the present invention includes domains that are substantially composed of second segments, which may be referred to herein as second-segment domains. It is further believed, without intending to be limited to any particular theory, that at least some (for example, at least a significant amount) of the photochromic compounds of the curable photochromic compositions of the present invention reside within the second-segment domains of the cured coatings or films.Furthermore, it is believed, without intending to limit oneself to any theory, that the photochromic compounds residing within the domains of the second segment have an enhanced range of molecular freedom / movement, allowing the photochromic compounds to make an easier and faster transition between open and closed forms, such as in response to exposure to and removal from an actinic radiation source, thereby resulting in improved photochromic performance properties associated with the cured article. The segmented polymer (b) can, in some embodiments, be present in the photochromic curable composition of the present invention in an amount from 20 to 98 percent by weight, or from 30 to 98 percent by weight, or from 40 to 98 percent by weight, or from 35 to 80 percent by weight, in each case based on the total weight of resin solids of the photochromic curable composition. As used herein, the term total weight of resin solids means the total weight of the segmented polymer and curing agent, and does not include the weight of the photochromic compound(s). The photochromic curable compositions of the present invention include a curing agent (c) comprising reactive functional groups that are reactive with the active hydrogen groups of the segmented polymer (b), ML / wherein the curing agent includes at least one of, a polyisocyanate, a polyisothiocyanate, or an aminoplast. The polyisocyanate curing (or crosslinking) agent includes at least two isocyanate (-NCO) groups. Examples of isocyanate functional materials from which the polyisocyanate curing agent may be selected include, but are not limited to, toluene-2,4-diisocyanate; toluene-2,6-diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenyl methane-2,4'-diisocyanate; para-phenylene diisocyanate; biphenyl diisocyanate; 3,3'-dimethyl-4,4'-diphenylene diisocyanate; tetramethylene-1,4-diisocyanate; hexamethylene-1,6-diisocyanate; 2,2,4-trimethylhexane-1,6-diisocyanate; lysine methyl ester diisocyanate; bis(ethyl isocyanate) fumarate; isophorone diisocyanate; ethylene diisocyanate; dodecane-1,12-diisocyanate; cyclobutane-1,3-diisocyanate; cyclohexane-1,3-diisocyanate; cyclohexane-1,4-diisocyanate; methyl cyclohexyl diisocyanate; hexahydrotoluene-2,4-diisocyanate; hexahydrotoluene-2,6-diisocyanate; hexahydrophenylene-1,3-diisocyanate;hexahydrophenylene-1,4-diisocyanate; perhydrodiphenylmethane-2,4'-diisocyanate; perhydrodiphenylmethane-4,4'-diisocyanate; norbornane diisocyanate; and mixtures thereof. The polyisocyanate curing agent may be selected from polyisocyanates prepared from dimers and trimers of diisocyanate monomers. The dimers and trimers of diisocyanate monomers may be prepared by methods recognized in the art, as described in U.S. Patent No. 5,777,061, column 3, line 44, column 4, line 40. The dimers and trimers of the aforementioned diisocyanate monomers may contain linkages selected from the group consisting of isocyanurate, urethdione, biuret, allophanate, and combinations thereof. The polyisocyanate curing agent may also be selected from an oligomeric polyisocyanate functional adduct. The oligomeric polyisocyanate functional adduct may contain structural linkages selected from urethane (-NH-C(O)-O-), thiourethane (-NHC(O)-S-), urea (-N(R1)-C(O )-N(Rx)-, where each R1 is independently as described above herein), or combinations of such structural linkages. As used herein, an oligomeric polyisocyanate functional adduct is defined as a material that is substantially free of polymer chain extension. Oligomeric polyisocyanate functional adducts can be prepared by recognized methods in the art, for example, from a compound containing three or more active hydrogen groups, such as trimethylolpropane (TMP), and an isocyanate monomer, such as l-isocyanate-3,3,5-trimethyl-5-isocyanatemethylcyclohexane (IPDI), in a molar ratio of 1:3, respectively. In the case of TMP and IPDI, by employing recognized reduced-feed and / or dilute-solution synthesis techniques, an oligomeric adduct having an average isocyanate functionality of 3 (TMP-3IPDI) can be prepared. The compound containing the active hydrogen group, used to prepare the functional oligomeric polyisocyanate adduct, may be aliphatic, such as TMP, trishydroxyisocyanurate, pentaerythritol, and trimethylolpropane tris(mercaptoacetate). The isocyanate monomer used to prepare the functional oligomeric polyisocyanate may be a diisocyanate monomer, for example, any of those described earlier in this document. The isocyanate groups of the polyisocyanate curing agent can be capped or blocked with a capping / blocking agent. After exposure to elevated temperature, the capping / blocking agent separates from the isocyanate-containing material, allowing its free / unblocked isocyanate groups to react and form covalent bonds with the active hydrogen groups of the segmented polymer. After the polyisocyanate is unblocked or deblocked, the capping agent may volatilize out of the composition (before the composition vitrifies) and / or remain in the composition, acting as a plasticizer. It is desirable that the capping agent does not bubble the composition and / or over-plasticize it after deblocking. The capping groups of the capped polyisocyanate curing agent can be selected from hydroxyl functional compounds, 1H-azoles, lactams, ketoximes, or mixtures thereof. Classes of compounds with hydroxyl functionality may include, but are not limited to, alkyl monoalcohols or aliphatic, cycloaliphatic, or aromatic phenols. Specific examples of compounds with hydroxyl functionality useful as capping agents include, but are not limited to, lower aliphatic alcohols such as methanol, ethanol, and n-butanol; cycloaliphatic alcohols such as cyclohexanol and tetrahydrofuran; aromatic alkyl alcohols such as phenylcarbinol and methylphenylcarbinol; and glycol ethers, for example, ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol moly ether, and propylene glycol methyl ether.Functional hydroxyl termination groups may include phenols, examples of which include, but are not limited to, phenol itself and substituted phenols such as cresol, nitrophenol, and p-hydroxyl methylbenzoate. Examples of lH-azoles that are useful as capping groups may include, but are not limited to, lH-imidazole, lH-pyrazole, lH-dialkyl pyrazoles (such as lH-3,5-dimethyl pyrazole and lH-2,5-dimethyl pyrazole), lH-1,2,3-triazole, lH-1,2,3-benzotriazole, lH-1,2,4-triazole, lH-5-methyl-l,2,4-triazole, and lH-3-amino-l,2,4-triazole. Ketoximes useful as capping groups may include those prepared from aliphatic or cycloaliphatic ketones. Examples of ketoxime capping groups include, but are not limited to, 2-propanone oxime (acetone oxime), 2-butanone oxime (also known as methyl ethyl ketoxime), 2-pentanone oxime, 3-pentanone oxime, 3-methyl-2-butanone oxime, 4-methyl-2-pentanone oxime, 3,3-dimethyl-2-butanone oxime, 2-heptanone oxime, 3-heptanone oxime, 4-heptanone oxime, 5-methyl-3-heptanone oxime, 2-dimethyl-4-heptanone oxime, cyclopentanone oxime, cyclohexanone oxime, 3-methylcyclohexanone oxime, 3,3,5-trimethylcyclohexanone oxime, and 3,5,5-trimethyl-2-cyclohexene-5-one oxime. Examples of lactam protective groups may include, but are not limited to, e-caprolactam and 2-pyrolidinone. Other suitable protective groups include morpholine, 3-aminopropylmorpholine, and N-hydroxyphthalimide. In the photochromic curable compositions of the present invention, at least some of the reactive functional groups of the curing agent can be blocked with a protecting group, and each protecting group can be selected independently from the group consisting of methyl ethyl ketoxime, pyrazole (more particularly, IH-pyrazole) and dialkylpyrazole (more particularly, lH-dialkylpyrazole). The polyisothiocyanate curing (or crosslinking) agent of the photochromic curable compositions of the present invention includes at least two isothiocyanate (-NCS) groups. The polyisothiocyanate curing agent may be selected from those classes and examples of polyisothiocyanate curing agents described above herein (including those in which the isocyanate groups are capped or blocked), in which the isocyanate (-NCO) groups thereof are replaced with isothiocyanate (-NCS) groups. The photochromic curable composition of the present invention typically also includes one or more curing catalysts to catalyze the reaction between the isocyanate and / or isothiocyanate groups of the polyisocyanate curing agent and the active hydrogen groups of the segmented polymer. Useful catalyst classes include, but are not limited to, metal compounds such as organotin compounds, organobismuth compounds, organozinc compounds, organozirconium compounds, organoaluminum compounds, organonickel compounds, organomercury compounds, and alkali metal compounds; and amine compounds such as tertiary amine compounds and quaternary ammonium compounds.Examples of organic tin compounds include, but are not limited to, tin(II) salts of carboxylic acids, such as tin(II) acetate, tin(II) octanoate, tin(II) ethylhexanoate, and tin(II) laurate; and tin(IV) compounds, such as dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate. Examples of suitable tertiary amine catalysts include, but are not limited to, diazabicyclo[2.2.2]octane and 1,5-diazabicyclo[4,3,0]non-5-ene. Examples of organic bismuth compounds include, but are not limited to, bismuth carboxylates. Examples of alkali metal compounds include, but are not limited to, alkali metal carboxylates, such as, but not limited to, potassium acetate and potassium 2-ethylhexanoate.Examples of quaternary ammonium compounds include, but are not limited to, N-hydroxyalkyl quaternary ammonium carboxylates. The catalyst can be selected from tin(II) octanoate, dibutyltin(IV) dilaurate, and / or bismuth 2-ethylhexanoate. The curing (or crosslinking) agent of the photochromic curable compositions of the present invention may be an aminoplastic curing agent. The aminoplastic curing agent may be selected from aminoplastic curing agents recognized in the art (or crosslinkers). Examples of suitable aminoplastic curing agents include, but are not limited to, aminoplastics containing methylol and / or methylol ether groups. Aminoplasts are typically obtained from the reaction of formaldehyde with an amine or amide. Examples of amines or amides include, but are not limited to, melamine, urea, and / or benzoguanamine. Condensates with other amines or amides, such as glycoluril aldehyde condensates, can also be used, yielding a high-melting-point crystalline product useful in powder coatings. Although formaldehyde is commonly used to prepare aminoplast crosslinking agents, other aldehydes, such as acetaldehyde, crotonaldehyde, and / or benzaldehyde, can be used. Aminoplastic curing agents typically contain methylol groups. At least some of these methylol groups are usually etherified with an alcohol to modify the curing response. Any monohydric alcohol can be used for this purpose, including, but not limited to, methanol, ethanol, butanol, isobutanol, and / or hexanol. Aminoplastic curing agents can be selected from melamine, urea, and / or benzoguanamine-formaldehyde condensates etherified with an alcohol containing one to four carbon atoms. When an aminoplastic curing agent is present, the photochromic curable compositions of the present invention typically include one or more catalysts to accelerate the curing of the aminoplastic curing agent with the active hydrogen groups of the segmented polymer. Suitable catalysts for curing aminoplastics include, but are not limited to, acids such as acid phosphates and sulfonic acids or substituted sulfonic acids. Examples include dodecylbenzenesulfonic acid, paratoluenesulfonic acid, phenyl acid phosphate, ethylhexyl acid phosphate, and the like. The catalyst is typically present in an amount of approximately 0.05 to approximately 5.0 percent by weight, or approximately 0.25 to approximately 2.0 percent by weight, based on the total weight of resin solids in the photochromic curable composition. The curing (or crosslinking) agent (c) may be present in the photochromic curable composition of the present invention in an amount from 2 to 80 percent by weight, or from 2 to 70 percent by weight, or from 2 to 60 percent by weight, or from 20 to 65 percent by weight, the weight percentages in each case being based on the total weight of resin solids of the photochromic curable composition, and inclusive of the listed values. The segmented polymer (b) may be present in the photochromic curable composition in an amount from 30 to 98 percent by weight, based on the total resin solids weight of the photochromic curable composition; and the curing agent may be present in the photochromic curable composition, in some embodiments, in an amount from 2 to 70 percent by weight, based on the total resin solids weight of the photochromic curable composition. The photochromic curable composition of the present invention may comprise a curing agent including at least one polyisocyanate and one polyisothiocyanate, wherein each reactive functional group of the curing agent is independently selected from isocyanate or isothiocyanate. The molar ratio of reactive functional groups of the curing agent (c) to active hydrogen groups of the segmented polymer (b) may be at least 4:1. Furthermore, the curing agent may include at least one polyisocyanate and / or polyisothiocyanate, where each reactive functional group of the curing agent is independently selected from isocyanate or isothiocyanate. The molar ratio of reactive functional groups of the curing agent (c) to the active hydrogen groups of the segmented polymer (b) is at least 5:1 and less than or equal to 60:1, such as from 6:1 to 50:1, or from 7:1 to 40:1. The polyisocyanate suitable for use in the curable composition of the present invention may include at least one of linear or branched aliphatic polyisocyanates, cycloaliphatic polyisocyanates, dimers thereof, and trimers thereof, including in each case, but not limited to, such classes and examples thereof as described above herein. Examples of linear or branched aliphatic polyisocyanates include, but are not limited to, ethylene diisocyanate; tetramethylene-1,4-diisocyanate; hexamethylene-1,6-diisocyanate; 2,2,4-trimethylhexane-1,6-diisocyanate; and dodecan-1,12-diisocyanate.Examples of cycloaliphatic polyisocyanates include, but are not limited to, cyclobutane-1,3-diisocyanate; cyclohexane-1,3-diisocyanate; cyclohexane-1,4-diisocyanate; cyclohexyl methyl diisocyanate; hexahydrotoluene-2,4-diisocyanate; hexahydrotoluene-2,6-diisocyanate; hexahydrophenylene-1,3-diisocyanate; hexahydrophenylene-1,4-diisocyanate; perhydrodiphenylmethane-2,4'-diisocyanate; and perhydrodiphenylmethane-4,4'-diisocyanate. The curable photochromic compositions of the present invention also include (a) at least one photochromic compound. The photochromic compound (a) may be selected from known classes and examples of photochromic compounds, and may include combinations or mixtures thereof. For example, though not limited to the purposes of this document, mixtures of photochromic compounds can be used to achieve certain activated colors, such as a near-neutral gray or a near-neutral brown. See, for example, U.S. Patent No. 5,645,767, col. 12, line 66 to col. 13, line 19, which describes the parameters defining neutral gray and brown colors and whose description is specifically incorporated by reference herein. The photochromic compound suitable for use in the curable photochromic compositions of the present invention may be selected from the group consisting of naphthopyrans, benzopyrans, phenanthropyrans, indenonaphthopyrans, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)-benzoxazines, fulgides, fulgimides, diarylethenes, and mixtures of such photochromic compounds. Additional examples of other photochromic compounds that can be used in the curable photochromic compositions of the present invention include, but are not limited to, those disclosed in column 34, line to column 35, line 13 of document US 9,028,728 B2, the description of which is specifically incorporated by reference in this document. The photochromic compound (a) is present in the photochromic curable composition in an amount at least sufficient to provide an article prepared from the composition with a desirable level of photochromic properties, referred to as the photochromic amount. The amount of photochromic compound(s) present in the photochromic curable composition may range from 0.001 percent to 40 percent by weight, or from 0.001 to 10 percent by weight, or from 0.01 to 5 percent by weight, or from 0.1 to 2.5 percent by weight, based on the total weight of solids in the photochromic curable composition (including the weight of the photochromic compound(s)), and inclusive of the values ​​mentioned. The photochromic curable compositions of the present invention may optionally contain additives such as, but not limited to, waxes for flowability and wetting; flow control agents, such as poly(2-ethylhexyl) acrylate; antioxidants; and ultraviolet (UV) light absorbers. Examples of useful antioxidants and UV light absorbers include, but are not limited to, those commercially available from BASF under the registered trademarks IRGANOX and TINUVIN. These optional additives, when used, may be present in amounts up to 20 percent by weight, based on the total weight of solids in the photochromic curable composition (excluding the solvent). The curable photochromic compositions of the present invention may further include one or more fixed-dye dyes. As used herein, the term fixed-dye and related terms, such as fixed dye, static dye, and static colorant, mean dyes that are non-photosensitive materials, which do not respond either physically or chemically to electromagnetic radiation with respect to visually observed color. The term fixed-dye and related terms as used herein do not include or distinguish photochromic compounds. As used herein, the term non-photosensitive materials means materials that do not respond physically or chemically to electromagnetic radiation with respect to their visually observed color, including, but not limited to, fixed-dye dyes. One or more fixed-dye dyes may be present in the photochromic curable compositions of the present invention for purposes including, but not limited to, providing a cured article prepared from the photochromic curable compositions with at least one base (or primer) color characteristic of the fixed-dye dye, when the photochromic compound is not activated; and optionally a second color characteristic of the combination of the fixed-dye dye and the photochromic compound when activated, such as when exposed to actinic radiation. The optional fixed dye of the photochromic curable composition comprises at least one of azo dyes, anthraquinone dyes, xanthene dyes, azime dyes, iodine, iodide salts, polyazo dyes, stilbene dyes, pyrazolone dyes, triphenylmethane dyes, quinoline dyes, oxazine dyes, thiazine dyes, or polyene dyes. The fixed dye may be present in the photochromic curable composition in varying amounts to provide the desired effect in the cured article prepared from it. For example, the fixed dye may be present in the photochromic curable composition in an amount from 0.001 to 15 percent by weight, or from 0.01 to 10 percent by weight, or from 0.1 to 2.5 percent by weight, the extreme percentage weights in each case being the total weight of solids in the photochromic curable composition (including the weight of the fixed dye; and inclusive of the values ​​mentioned). The photochromic curable compositions herein may include solvents such as those selected from water, organic solvents, and combinations thereof. The classes of organic solvents that may be present in the curable photochromic compositions of the present invention include, but are not limited to, alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, furfuryl alcohol, and tetrahydrofurfuryl alcohol; ketones or ketoalcohols, such as acetone, methyl ethyl ketone, and diacetone alcohol; ethers, such as dimethyl ether and methyl ethyl ether; cyclic ethers, such as tetrahydrofuran and dioxane; esters, such as ethyl acetate, ethyl lactate, ethylene carbonate, and propylene carbonate; hydroxyfunctional ethers of alkylene glycols, such as butyl 2-hydroxyethyl ether, methyl 2-hydroxypropyl ether, and phenyl 2-hydroxypropyl ether; cyclic compounds containing nitrogen, such as pyrrolidone, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone; compounds containing sulfur, such as dimethyl sulfoxide and tetramethylene sulfone;aromatic compounds, such as toluene, xylene, anisole, and butyl benzoate; and mixtures of aromatic compounds, such as, but not limited to, Aromatic 100 Fluid, which is a commercially available mixture of dialkyl and trialkyl Cg-Cio-benzenes.; Solvents may be present in the photochromic curable compositions of the present invention in an amount from 5 to 95 percent by weight, or from 15 to 80 percent by weight, or from 30 to 60 percent by weight, in each case based on the total weight of the photochromic curable composition (including the weight of the solvent). The present invention also relates to articles, and in particular to photochromic articles prepared using the curable photochromic composition of the present invention as described above. Examples of photochromic articles that can be prepared using the curable photochromic compositions of the present invention may include, but are not limited to, ophthalmic articles, display articles, windows, and mirrors. The curable photochromic compositions of the present invention can be used to prepare photochromic layers, such as photochromic coatings and photochromic films (or sheets). As used herein, the term coating means a cured, non-self-supporting layer, generally formed from a liquid composition that is applied and adheres to a substrate, and which may or may not have a uniform thickness. As used herein, the term film (or sheet) means a cured polymeric layer that is self-supporting (i.e., independent) and has a substantially uniform thickness. The photochromic curable composition of the present invention can be cured by any suitable method. The photochromic curable composition can be cured under ambient conditions, such as at room temperature of approximately 25°C. Alternatively, the photochromic curable composition can be cured by exposure to elevated temperature (above ambient temperature). As used herein, curing means the formation of a three-dimensional crosslinking network through the formation of covalent bonds, such as between the active hydrogen groups of the segmented polymer and the reactive functional groups of the curing agent. When cured at elevated temperature, the photochromic curable composition may be referred to herein as a thermoset photochromic curable composition.The temperature at which the thermosetting photochromic curable composition of the present invention cures is variable and depends in part on the amount of time during which the curing takes place. The photochromic curable composition of the present invention can be cured at an elevated temperature from 90°C to 204°C, or from 100°C to 177°C, or from 110°C to 140°C for a period of 20 to 240 minutes. The present invention also relates to an article, such as a photochromic article, comprising (A) a substrate; and (B) a photochromic layer on at least one surface of the substrate, wherein the photochromic layer is formed from any of the curable photochromic compositions mentioned above of the present invention. The article, which includes a substrate and a photochromic coating on at least one surface of the substrate (formed from the curable photochromic composition of the present invention), may be selected from ophthalmic articles, display articles, windows, or mirrors. Accordingly, the substrate of the article may be selected from ophthalmic substrates, displays, windows, or mirrors. The substrate may be composed of one or more suitable materials, including, but not limited to, organic materials, such as organic polymeric materials; glasses, such as silica-based glasses; metals; ceramic materials; and combinations thereof. Non-limiting examples of organic materials that may be used to form the substrate of the articles of the present invention include polymeric materials, for example, homopolymers and / or copolymers, prepared from the monomers and monomer mixtures disclosed in U.S. Patent 5,962,617 and U.S. Patent 5,658,501 from column 15, line 28 to column 16, line 17, the descriptions of which are specifically incorporated herein by reference. For example, such polymeric materials may be thermoplastic or thermoset polymers, may be transparent or optically clear, and may have any required refractive index. Non-limiting examples of such monomers and polymers disclosed include polyol (allyl carbonate) monomers, for example, allyldiglycol carbonates such as bis(allyl carbonate) diethylene glycol,whose monomer is sold under the brand name CR-39 by PPG Industries, Inc.; polyurea-polyurethane (polyurea-urethane) polymers, prepared, for example, by the reaction of a polyurethane prepolymer and a diamine curing agent, a composition for such a polymer being sold under the brand name TRIVEX by PPG Industries, Inc.; carbonate monomer terminated in polyol(meth)acryloyl; diethylene glycol dimethacrylate monomers; ethoxylated phenol methacrylate monomers; diisopropenylbenzene monomers; ethoxylated trimethylol propane triacrylate monomers; ethylene glycol methacrylate monomers; poly(ethylene glycol) bismethacrylate monomers; urethane acrylate monomers; poly(bisphenol A ethoxylated dimethacrylate); poly(vinyl acetate); poly(vinyl alcohol); poly(vinyl chloride); poly(vinylidene chloride); polyethylene; polypropylene; polyurethanes; polyurethanes; thermoplastic polycarbonates,such as carbonate-bonded resin derived from bisphenol A and phosgene, such material being sold under the brand name LEXAN; polyesters, such as the material sold under the brand name MYLAR; poly(ethylene terephthalate); polyvinyl butyral; poly(methyl methacrylate), such as the material sold under the brand name PLEXIGLAS; and polymers prepared by reacting polyfunctional isocyanates with polythiols or polyepsilon monomers, either homopolymerized or co- and / or terpolymerized with polythiols, polyisocyanates, polyisothiocyanates, and optionally ethylenically unsaturated monomers or vinyl monomers containing halogenated aromatic compounds. Copolymers of such monomers and mixtures of the polymers and copolymers described with other polymers are also contemplated, for example, to form block copolymers or interpenetrating network products. The substrate may optionally include a photochromic material and / or a fixed-dye, each of which may be selected from the classes and examples of photochromic materials and fixed-dyes described earlier herein. The optional photochromic materials / composites in the substrate may be the same as or different from the photochromic compounds of the photochromic layer. The optional fixed-dye may be the same as or different from the optional fixed-dye dyes of the photochromic layer. The photochromic layer of the article may be a photochromic coating and / or a photochromic film (or sheet). The photochromic film or sheet may be formed according to methods recognized in the art, such as, but not limited to, extrusion and casting methods. The photochromic layer of the article may be a photochromic coating layer formed from the curable photochromic composition of the present invention.The photochromic curable coating composition can be applied to the substrate according to methods recognized in the art, which include, but are not limited to, spray application methods, curtain coating application methods, knife (or stick) application methods, dip application methods, coating application methods, rotary coating application methods, jet printing methods (such as inkjet printing methods, wherein the ink is replaced by a photochromic curable composition according to the present invention), and combinations thereof. After the application of the photocurable composition to at least one substrate surface, the applied photocurable coating composition cures, as described above, to form a photochromic coating layer. The photochromic coating layer may be in the form of a single layer or multiple layers. When in the form of multiple layers, each layer of the photochromic coating may be prepared from photocurable compositions according to the present invention, having identical or different compositions, such as identical or different photochromic compounds. The photochromic layer can be any suitable thickness, such as from 10 micrometers to 250 micrometers, or from 15 micrometers to 75 micrometers. In addition to the photochromic layer, the article may optionally include one or more layers recognized in the art, such as, but not limited to, a primer layer or layers; an adhesive layer(s); a protective layer or layers (such as a hard coating layer); a polarizing layer or layers; a birefringent layer(s); an antireflective layer(s); and / or other photochromic layer(s) prepared from a composition other than the curable photochromic composition of the present invention. The present invention further relates to a multilayer photochromic article comprising at least one photochromic layer formed from the curable photochromic composition of the present invention. Each layer of the multilayer photochromic article may independently be in the form of a coating or a film / sheet. The multilayer photochromic article may include two or more layers formed from identical or different curable photochromic compositions of the present invention. The multilayer article of the present invention may optionally include one or more layers recognized in the art, such as, but not limited to, an adhesive layer or layers; a protective layer(s) (such as a hard coating layer or one or more polymer film layers); a polarizing layer(s); a birefringent layer(s); an antireflective layer(s); and / or other photochromic layer(s) prepared from a composition other than the curable photochromic composition of the present invention. The multilayer article of the present invention can have any suitable thickness, such as from 10 micrometers to 1000 micrometers, or from 15 micrometers to 750 micrometers, or from 25 to 100 micrometers. The multilayer article of the present invention may be used alone or in conjunction with another article, such as a substrate. The substrate may be selected from those classes and examples of substrates described earlier herein with respect to the article of the present invention, such as ophthalmic substrates, screens, windows, and / or mirrors. The substrate may be composed of one or more suitable materials, including, but not limited to, organic materials, such as organic polymeric materials; glasses, such as silica-based glasses; metals; ceramic materials; and combinations thereof. The multilayer article of the present invention can be adhered to the surface of a substrate by methods recognized in the art, such as, but not limited to, static adhesion, as with static electricity; one or more interposed adhesive layers; fusion bonding, such as thermal fusion bonding; and mold forming, such as when the multilayer article is placed in a mold, and the substrate is formed against at least one surface of the multilayer article within the mold. The multilayer article of the present invention can be supported by one or more supports that are securely coupled to one or more peripheral regions of the multilayer article. The present invention may be further characterized by one or more of the following non-limiting clauses. Clause 1. A curable photochromic composition comprising: (a) a photochromic compound; (b) a segmented polymer comprising active hydrogen groups, at least a first segment, and at least a second segment, wherein: (i) each first segment independently comprises a fluorinated polymer segment, and (ii) each second segment independently comprises a segment selected from the group consisting of a polycarbonate segment, a polyester segment, a polyether segment, a polyurethane segment, and a copolymer segment thereof; and (c) a curing agent comprising reactive functional groups that are reactive with the active hydrogen groups of the segmented polymer, wherein the curing agent comprises at least one of a polyisocyanate, a polyisothiocyanate, or an aminoplast. Clause 2. The photochromic curable composition according to clause 1, wherein at least a portion of each second segment (ii) is terminated with a group derived from an active hydrogen-containing compound selected from the group consisting of iH-azoles, alkyl alcohols, and mixtures thereof. Clause 3. The photochromic curable composition of clauses 1 or 2, wherein: The segmented polymer (b) has an active hydrogen equivalent weight of from 1,000 to 15,000 g / eq, and each active hydrogen group of the segmented polymer (b) is independently selected from the group consisting of hydroxyl groups, thiol groups, primary amine groups, and secondary amine groups. Clause 4. The photochromic composition curable according to any one of clauses 1 to 3, wherein each active hydrogen group of the segmented polymer (b) is hydroxyl. Clause 5. The photochromic composition curable according to any one of clauses 1 to 4, wherein at least a first segment (i) and at least a second segment (ii) are covalently linked to each other by a linking group selected from the group consisting of a carboxylic acid ester linking group, a thioester linking group, an amide linking group, a urethane linking group, a thiourethane linking group, a urea linking group, a thiourea linking group, a carbonate linking group, an ether linking group, and a thioether linking group. Clause 6. The photochromic curable composition according to any one of clauses 1 to 5, wherein the second segment (ii) is present in the segmented polymer (b) in an amount from 40 percent by weight to 95 percent by weight, based on the total weight of the segmented polymer. Clause 7. The photochromic curable composition according to any one of clauses 1 to 6, wherein the photochromic curable composition comprises a total number of second segments (ii) of from 15 percent by weight to 50 percent by weight, based on the total solids weight of the photochromic curable composition. Clause 8. The photochromic composition curable according to any one of clauses 1 to 7, wherein each second segment (ii) independently comprises at least one of a polycarbonate segment, a polycarbonate-polyester segment, a polycarbonate-polyurethane segment, a polyether segment, and / or a polycarbonate-polyester-polyurethane segment. Clause 9. The photochromic composition according to any one of clauses 1 to 8, wherein: the curing agent (c) comprises at least one of a polyisocyanate comprising reactive isocyanate groups, and / or a polyisothiocyanate comprising reactive isothiocyanate groups, and A molar ratio of reactive functional groups of the curing agent (c) to active hydrogen groups of the segmented polymer (b) is at least 4:1. Clause 10. The photochromic composition curable according to any one of clauses 1 to 9, wherein the molar ratio of reactive functional groups of the curing agent (c) to active hydrogen groups of the segmented polymer (b) is at least 5:1 and less than or equal to 60:1. Clause 11. The photochromic composition curable according to any one of clauses 1 to 10, wherein the curing agent (c) comprises a polyisocyanate, comprising reactive isocyanate groups. Clause 12. The photochromic composition curable according to clause 11, wherein the polyisocyanate is an aliphatic polyisocyanate, Clause 13. The photochromic composition curable according to any one of clauses 1 to 12, wherein the curing agent (c) comprises a polyisocyanate and at least some of the reactive isocyanate groups comprising the polyisocyanate curing agent are blocked with a blocking agent, and each blocking agent is independently selected from the group consisting of methyl ethyl ketoxime, pyrazole, and dialkylpyrazole. Clause 14. The photochromic composition curable according to any one of Clauses 1 to 13, wherein the photochromic compound (a) is selected from the group consisting of naphthopyrans, benzopyrans, phenanthropyrans, indenonaphthopyrans, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)benzoxazines, fulgides, fulgimides and mixtures of such photochromic compounds. Clause 15. The photochromic composition curable according to any one of clauses 1 to 14, wherein the fluorinated polymer segment comprises an active hydrogen group. Clause 16. A photochromic polymeric film comprising the photochromic composition curable according to any one of clauses 1 to 15. Clause 17. An article comprising: (A) a substrate; and (B) a photochromic layer on at least one surface of the substrate, wherein the photochromic layer is formed from the photochromic composition curable according to any one of clauses 1 to 15. Clause 18. A multi-layer photochromic article comprising at least one photochromic layer formed from the photochromic composition curable according to any one of clauses 1 to 15. Clause 19. The multilayer photochromic article according to clause 18, wherein at least one photochromic layer is a photochromic coating layer and / or a photochromic polymeric film layer. The present invention is described more particularly in the following examples, which are intended to be illustrative only, since numerous modifications and variations thereof will be evident to those skilled in the art. Unless otherwise specified, all parts and all percentages are by weight. EXAMPLES Part A: Preparation of the Second Segmented Polymer Segment The materials used in the preparation of the polycarbonate-polyester diol segments are summarized in Table 1. Each of the polycarbonate-polyester diol segments was synthesized in a round-bottom flask equipped with a mechanical stirrer and a Dean-Stark trap. After the introduction of Charge 1, each reaction mixture was heated under a layer of nitrogen to 170°C, resulting in strong reflux. Xylenes and water were removed from the Dean-Stark trap as needed to maintain the temperature below 180°C for up to 7 hours, at which point the acid number was measured to be <1 mg KOH / g. At this point, the reaction mixture was cooled to 130°C and then reduced to the solids level indicated in Table 1 by the addition of Charge 2. Table 1: Preparation of the second segments of segmented polymer Sl to S-6. Components Parts by Weight Sl S-2 S-3 S-4 S-5 S-6 Charge 1 DURANOL™ T56521 1735.9 1814.3 1884.2 ETERNACOLL® PH-200D2 754.0 1804.9 1710.7 Adipic Acid 98.4 46.1 102.8 106.8 102.3 103.2 Triphenyl Phosphite 3.6 1.6 3.8 3.9 3.8 3.7 Monobutyl Hydroxide Oxide 1.8 0.8 1.9 2.0 1.9 1.8 Aromatic 150 179 110.57 170 177 240.4 91 Xylenes 200 118.5 208 216 280.8 221 Load 2 Aromatic 150 205.66 640 842 1359 1433 Anniso 1 596 Solids Production 65 65.9 63.8 61.4 51.2 51 Total (% by weight)3 Number average molecular weight (Mn) 10,800 12,000 12,164 10,900 12,000 11,700 Polydispersity index 2.13 2.25 2.32 2.3 1.99 2.17 OH4 value 10.3 9.4 9.9 9.9 8.5 7.2 Acidity index5 0.1 0.2 0.1 0.3 0.2 0.2 MA / LEFT / ¿U¿¿ / UOO¿OU . A diol polycarbonate from Asahi 2. A polycarbonate diol from Ube 3. % of solids measured after one hour in an oven at 120°C. 4. OH value as determined by ASTM method D4274. 5. Residual acid material as determined by ASTM DI639 method. Part B; Preparation of Segmented Polymers The preparation of segmented polymers (CE.l) to (Ex.8) is described as follows with reference to Table 2. Table 2: Preparation of Segmented Polymers Samples (Parts by weight of solution) Load Components CE. 1 Ex . 2 Ex . 3 Ex . 4 Ex . 5 Ex . 6 Ex .7 Ex . 8 A Sl 117.6 117.8 S-2 107.8 S-3 63.7 119.1 S-4 111.3 S-5 101.9 S-6 505.6 B TMDI6 4.3 4.4 3.6 2.1 3.8 3.8 2.7 15.4 C Dibutyl ester ñodilaurate 0.09 0.1 0.09 0.08 0.1 0.09 0.34 KKat3487 0.25 D Tinuvin 1528 6.4 3.4 6.9 4.9 E 1-Butanol 0.76 0.77 0.29 0.33 2.71 F Polyol (meth)acrylic co9 18.1 LF91610 18.2 16 LF91611 9.5 LF20012 63.9 LF972113 13.1 LF91014 46 93.5 Product % of solids 3 32 33 33 30 35 32 36 38 Average molecular weight (Mw) 62.00 0 87.40 0 145.0 00 233.000 92.30 0 135.0 00 66.70 0 78.00 0 PDI 3.8 3.5 3.9 6.9 2.6 3.7 2.4 4 % Load A and B 87 81 82 53 85 78 61 81 OH15 equivalent weight 4200 4700 9200 2700 4400 4800 1700 5000 6. A branched diisocyanate with methyl groups (an approximate 1:1 mixture of 2,2,4 and 2,4,4-trimethylhexamethylene diisocyanate) from Evonik Industries with an NCO equivalent weight of 105. 7. A bismuth carboxylate catalyst from King Industries. 8. A hindered amine light stabilizer from BASF with an OH equivalent weight of 756. 9. The (meth)acrylic polyol segment corresponds to the acrylic polyol of Table 6 of WO 2017 / 030545 Al and was prepared by free radical polymerization of hydroxypropyl methacrylate (40.4%), butyl methacrylate (57.6%) and acrylic acid (2.0%), and had: a total solids content of 61.5% by weight; a Mη of 3920; a polydispersity index of 1.58; and a theoretical equivalent weight of hydroxyl (in solids) of 360. 10. Lumiflon® fluoroethylene vinyl ether polyol available from Asahi Glass, the sample used had an OH value of 96 and a % solids of 99%. 11. Batch of Lumiflon® LF916 with an OH value of 104 and a % solids of 99%. Lumiflon® fluoroethylene vinyl ether polyol available from Asahi Glass, the sample used had an OH value of 30.9 (solution) and a % solids of 60%. 13. Lumiflon® fluoroethylene vinyl ether polyol available from Asahi Glass, the sample used had an OH value of 116 (solution) and a % solids of 70%. 14. Lumiflon® fluoroethylene vinyl ether polyol available from Asahi Glass, the sample used had an OH value of 68 (solution) and a % solids of 66.2%. 15. The equivalent weight of OH was calculated by dividing the mass of the resin solids by the difference between the sum of the moles of alcohol from the alcohol-containing charges (A, D, E and F) and the sum of the moles of isocyanate from the isocyanate-containing charge (B). MA / IZ / ¿U¿¿ / UOO¿OU Segmented Polymer CE.l According to Table 2, charges A, B, and C were combined with anisole (121 g) and heated to 80°C for 2.5 hours. The sample was cooled to 75°C, and charge E was added in anisole (16 g). After 10 minutes, charge F was added along with anisole (5 g). After 30 minutes at 75°C, the temperature was increased to 80°C for 3.5 hours. Tests using Surface SWYPE™ pads (available from CLI Laboratories Inc.; a drop of reaction solution placed on a pad causes a color change to orange or red when free isocyanates are present) indicated that isocyanate was still present. 1-Propanol (2 ml) was added to extinguish the reaction and, after 1.5 hours, tests with Surface SWYPE™ pads indicated that no isocyanate was present and the solution was cooled, yielding a viscous liquid. Segmented Polymer Ex.2 According to Table 2, charges A, B, and C were combined with anisole (116 g) and heated to 80°C for 2.5 hours. The sample was cooled to 70°C, and charge E in anisole (13 g) was added. After 10 minutes, charge F dissolved in anisole (28 g) was added along with additional anisole (8 g). After 30 minutes at 70°C, the temperature was increased to 80°C for another 2.5 hours. Tests using Surface SWYPE™ pads indicated that no isocyanate was present, and the solution was cooled to a viscous liquid. Segmented Polymer Ex. 3 According to Table 2, charges A, B, and C were combined with Aromatic 150 (87 g) and heated to 80°C for 2.5 hours. The sample was then cooled to 75°C, and charge D, dissolved in Aromatic 150 (27 g), was added. After 10 minutes, charge F, dissolved in Aromatic 150 (34 g), was added along with an additional 8 g of Aromatic 150. After 30 minutes, the temperature was increased to 80°C for 2 hours. Tests using Surface SWYPE™ pads indicated the absence of isocyanate, and the solution was cooled to a viscous liquid. Segmented Polymer Ex.4 According to Table 2, charges A, B, and C were combined with m-xylene (129 g) and heated to 80°C for 2.5 hours. The sample was cooled to 70°C, and charge E in m-xylene (14 g) was added. After 10 minutes, charge F was added. After 60 minutes at 70°C, the temperature was increased to 85°C for 1 hour. Tests with Surface SWYPE™ pads indicated that no isocyanate was present, and the solution was cooled to a viscous liquid. Segmented Polymer Ex. 5 According to Table 2, charges A, B, and C were combined with Aromatic 150 (90 g) and heated to 80°C for 2.5 hours. The sample was then cooled to 75°C, and charge D, dissolved in Aromatic 150 (1 g), was added along with an additional 4 g of Aromatic 150. After 30 minutes, charge E was added in Aromatic 150 (7 g). After 10 minutes, charge F was added along with an additional 11 g of Aromatic 150. After another 30 minutes, the temperature was increased to 80°C for 2 hours. Tests using Surface SWYPE™ pads indicated that no isocyanate was present, and the solution was cooled to a viscous liquid. Segmented Polymer Ex. 6 According to Table 2, charges A, B, and C were combined with Aromatic 150 (0 g) and heated to 80°C for 2.5 hours. The sample was cooled to 75°C, and charge D, dissolved in Aromatic 150 (10 g), was added along with an additional 4 g of Aromatic 150. After 30 minutes, charge F, dissolved in Aromatic 150 (24 g), was added along with an additional 10 g of Aromatic 150. After 2.5 hours, tests using Surface SWYPE™ pads indicated the presence of isocyanate. 1-Propanol (2 mL) was added to quench the reaction, and after 30 minutes, tests using Surface SWYPE™ pads indicated the absence of isocyanate. The solution was then cooled, resulting in a viscous liquid. Segmented Polymer E j.7 According to Table 2, charges A, B, and C were combined with Aromatic 150 (41g) and heated to 80°C for 2.5 hours. The sample was cooled to 75°C and charge D dissolved in Aromatic 150 (16 g) was added. After 30 minutes, charge F dissolved in Aromatic 150 (9 g) was added. After another 30 minutes, the temperature was increased to 80°C for 2 hours. Tests with Surface SWYPE™ pads indicated that no isocyanate was present, and cooling the solution yielded a viscous liquid. Segmented Polymer Ex. 8 According to Table 2, charges A, B, and C were combined with Aromatic 150 (251 g) and heated to 80°C for 3 hours. The sample was cooled to 70°C, and charge E, mixed with Aromatic 150 (6 g), was added. After 30 minutes, charge F was added. After 2 hours, tests using Surface SWYPE™ pads indicated that no isocyanate was present, and the solution was cooled, resulting in a viscous liquid. Part C: Preparation of Photochromic Solution The photochromic solutions (A) and (B) were prepared by mixing the materials listed in Table 3 at room temperature until it was observed that all the solids had dissolved. MA / IZ / ¿U¿¿ / UOO¿OU Table 3 Photochromic solution Component Parts by weight Components AB Photochromic dyes 16 14.7 9.7 TINUVIN 14417 4.9 3.2 IRGANOX 2 4 518 4.9 3.2 Tamisolve™ NxG19 75.5 41.9 Aromatic 150 28.0 Propylene Carbonate 14.0 16. A mixture of selected photochromic indenfused naphthopyran dyes to provide a greenish-gray color. 17. A hindered amine light stabilizer from BASF: bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-[[3,5-bis(1,1-dimethylethyl)-4-hydroxypheni1]methyl]butylmalonate. 18. An antioxidant from BASF: triethylene glycol bis (3-tert-butyl-4hydroxy-5-methylphenyl)propionate. 19. An available solvent from Eastman Preparation of comparative and invention-curable photochromic compositions. Comparative Curable Photochromic Compositions: Comparative photochromic curable compositions (CE-9, CE-10) were prepared from the components listed in Table 4. CE-9 is a representative photochromic curable composition using a fluorinated polyol and polycarbonate diol segments as individual components. CE-10 is representative of a photochromic curable composition using a segmented polymer composed of a (meth)acrylic polyol and polycarbonate polyester diol segments. Table 4: Comparative Examples Component Charge 1 CE. 9 CE. 10 ETERNACOLL® PH-300D20 32.0 Segmented Polymer CE.1 120.6 Photochromic Solution (A) 40.9 Photochromic Solution (B) 61.9 Tamisolve™ NxG 19.7 TRIXENE® BI-796021 91.3 87.4 Charge 2 γ-Glycidoxypropionate 4.5 4.5 K-KAT® 348 1.1 dibutyltindilaurate 0.3 BYK® 33322 0.08 0.08 LF91014 6.3 20. A polycarbonate diol with a hydroxyl equivalent weight of 1.516, available from UBE Industries. 21. A hexamethylene diisocyanate biuret, blocked with 3,5-dimethylpyrazole, available from Baxenden Chemical Co with an equivalent weight of 410. 22. A polyether modified polydimethylsiloxane from BYK-Chemie, USA. Examples of Photochromic Compositions Curable According to the Present Invention: Examples 11 to 17 of the photochromic curable composition of the invention were prepared from the components listed in Table 5. The examples were prepared according to the procedure described above for the comparative examples. MA / IZ / ¿U¿¿ / UOO¿OU > Pi h C hh C cchcc Table 5 Load 1 Parts by Weight Components Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 Ex. 16 Ex. 17 Segmented Polymer Ex. 2 126.9 Segmented Polymer Ex. 3 124.9 Segmented Polymer Ex. 4 189.2 Segmented Polymer Ex. 5 113.8 Segmented Polymer Ex. 6 135.3 Segmented Polymer Ex. 7 146.4 Segmented Polymer Ex. 8 177.0 Photochromic Solution (A) 40.8 Photochromic Solution (B) 60.9 62.1 61.0 62.2 61.0 59.4 Tamisolve™ NxG 17.6 Load 2 Parts by Weight co TRIXENE® BI-7960 83.2 84.5 62.9 86.0 81.0 65.7 46.8 co M γ-Glycidoxypropyltrimethoxysilane 4.5 4.5 4.5 4.5 4.5 4.5 4.3 K-KAT® 348 1.1 1.1 0.7 1.1 1.1 1.1 0.6 BYK® 333 0.08 0.08 0.08 0.08 0.08 0.08 0.08 Filler 3 Parts by Weight Tamisolve™ NxG 25.1 43.5 24.2 11.3 9.0 Aromatic 150 6♦0 Propylene Carbonate 3.0 Product % of Filler A and B from Table 2 based on solids of resin 29.4 29.4 25.7 29.3 29.2 28.2 47.5 NCO:OH ratio 22.8 46.0 7.3 23.2 21.9 5.2 8.5 After preparation, the photochromic curable compositions of Examples 9 to 17 were each placed in a WHEATON® 348923-A Benchtop Roller for a minimum of six hours prior to use. Part D: Preparation of Test Specimens. Each of the curable photochromic composition examples prepared above in Part C was applied to a GENTEX® PDQ® coated flat polycarbonate lens (available from Gentex Optics, Inc.) with a diameter of 76 millimeters. All lens substrates were treated with oxygen plasma at a flow rate of 100 milliliters (mL) per minute of oxygen at 100 W power for three minutes, then coated with each of the curable photochromic composition examples described in Part C by spin coating. Approximately 1–2 mL of each curable photochromic composition was dispensed onto the lens substrate, which was then spun for 8–13 seconds at a spin rate sufficient to deposit enough wet coating onto the lens to produce similar activated optical densities, as described below in Part E.The parameters of the spin coating are reported in Table 6. Table 6. Centrifugal Coating Parameters and Weights of Coating Measures with Respect to the Preparation of Test Specimens. Example Centrifugation Time (s) Centrifugation Speed ​​(rpm) Weight of Photochromic Coating (g) CE . 9 9 1256 0.27 CE. 10 10 1231 0.38 Ej · 11 11 1334 0.42 Ej · 12 11 1131 0.44 Ej · 13 12 1428 0.39 Ej · 14 11 1366 0.42 Ej · 15 10 1615 0.41 Ej · 16 8 867 0.40 Ej · 17 13 1366 0.40 The coated lens substrates were prepared in duplicate and designated Lens Assemblies A and Lens Assemblies B. The coated lens substrates were then placed in an oven at 40°C until all the coated lens substrates had accumulated. The 40°C-treated coated lens substrates were then cured in a forced-air oven at 125°C for one hour and subsequently cooled to room temperature. The test specimens from Lens Assemblies A were then subjected to further heat curing for three hours at 105°C and set aside for hardness evaluation. The test specimens from Lens Assemblies B were further treated with oxygen plasma as described above and coated with HI-GARD® 1080S hard coating, a protective coating available from PPG Industries, Inc.The HI-GARD® 1080S hard coating was applied by spin-on, and each lens (from Lens Set B) was then re-cured at 105°C for three hours. The photochromic properties of the final lenses (test specimens) from Lens Set B were then evaluated. Part E: Test Methods and Test Results of the Test Specimens Prepared in Part D. Test specimens of lens assembly A were subjected to microhardness testing using a Fischerscope HCV, model H100SMC (available from Fischer Technology, Inc.) at a penetration depth of 2 micrometers after a load of 100 Newtons for 15 seconds. Each test specimen was measured from 2 to 5 times, and the microhardness results were averaged and tabulated in Table 15. The photochromic performance of test specimens from lens assembly B was tested on the photochromic test bench (PTB) manufactured by Essilor, Ltd., France. The PTB was maintained at a constant temperature of 23°C during the test. Prior to testing on the PTB, each test specimen was exposed to 365-nanometer (nm) ultraviolet light for approximately 10 minutes at a distance of about 14 centimeters to activate the photochromic materials. The UVA irradiance (315 nm to 380 nm) on the test sample was measured using a LICOR® Model Li-1800 spectroradiometer and found to be 22.2 watts per square meter (W / m²). Each test sample was then placed under a 500 watt (W) high-intensity halogen lamp for approximately 10 minutes at a distance of approximately 36 centimeters to bleach (inactivate) the photochromic materials.The illuminance on the test specimen was measured using the LICOR® spectroradiometer and found to be 21.9 klux. Each test sample was then kept in a dark environment at room temperature (21–24 °C) for at least one hour before testing on the BMP. Prior to measurement, the ultraviolet absorbance of each test sample was measured at 390 nm. The BMP was equipped with two 150 W Newport model no. 6255 xenon arc lamps positioned at right angles to each other. The light path from Lamp 1 was directed through a 3 mm SCHOTT® KG2 bandpass filter and appropriate neutral density filters, which contributed to the required partial visible and UV irradiance level. The light path from Lamp 2 was directed through a SCHOTT® KG bandpass filter. A 3 mm ML / t / ZUZZ / UOOZOU, a 400 nm SCHOTT® shortband cutoff filter, and appropriate neutral density filters were used to provide supplemental visible light illuminance. A 50% spot beam splitter (5.1 cm x 5.1 cm) (2 in x 2 in) set at 45° for each lamp was used to mix the two beams. The combination of neutral density filters and xenon arc lamp voltage control was used to adjust the irradiance intensity. Software (BMPSoft version 2.le) on the BMP was used to control time, irradiation, air cell and sample temperatures, shutdown, filter selection, and response measurement. A ZEISS® MCS 601 spectrophotometer with fiber optic cables for through-lens light delivery was used for response and color measurement. Photopic response measurements were collected on each test specimen. The BMP output power (i.e., the light dose to which the test sample was exposed) was set to 6.7 W / m²UVA, integrated from 315 to 380 nm, and an illuminance of 50 klux, integrated from 380 to 780 nm. This power setpoint was measured using an irradiance probe and a calibrated Zeiss spectrophotometer. The lens sample cell (test sample) was equipped with a quartz window and a self-centering sample holder. The temperature in the sample cell was controlled at 23°C using software with a modified Facis FX-10 environment simulator. The dynamic photochromic response and color of the test sample were measured using the same Zeiss spectrophotometer with fiber optic cables to deliver light from a tungsten halogen lamp through the sample.The collimated monitoring light beam of the fiber optic cable was kept perpendicular to the test specimen as it passed through the specimen and was directed to a receiver fiber optic cable assembly connected to the spectrophotometer. The exact placement point of the test specimen in the sample cell was where the activation xenon arc beam and the control light beam intersected to form two concentric circles of light. The angle of incidence of the xenon arc beam at the test specimen placement point was approximately 30° from the perpendicular. Response measurements, in terms of the change in optical density (AOD) from the inactive (bleached) state to the activated (colored) state, were determined by establishing the initial inactive transmittance and then opening the shutter of the xenon lamp(s) and measuring the transmittance throughout activation at selected time intervals. AOD at saturation was the absorbance measured after 15 minutes of exposure. The change in optical density was determined using the formula: AOD = log10(%Tb / %Ta), where %Tb is the percentage transmittance in the bleached state and %Ta is the percentage transmittance in the activated state. Optical density measurements were based on photopic optical density. An Atlas CI4000 meteorometer was used to perform simulated solar radiation-accelerated aging. Samples were exposed for a 1-hour dark cycle with the black panel, the chamber temperature at 40°C, and the relative humidity at 45%. This was followed by a 65-hour light cycle using a boron / boron silicate-filtered xenon arc lamp with an output of 0.25 watts per square meter at 340 nm. The temperature in the meteorometer was maintained at 40°C, and the relative humidity was controlled at 70%. The black panel temperature was maintained at 55°C. After the lenses were subjected to this UV exposure fatigue cycle, the lenses were preconditioned and measured on the optical bench to obtain the Δ DOfinai under the same conditions as described for the initial test. The fatigue percentage was determined by measuring the difference between the change in optical density (ADO) of the test sample before and after accelerated weathering according to the formula: % Fatigue = (ADOinic-ADOfinai) / AnOinic x 100. The results of the microhardness, attenuation half-life (T1 / 2), ADO at saturation, and fatigue tests of the photochromic dye are shown in Table 7. The ADO at saturation is after 15 minutes of activation. The attenuation half-life (Ti / 2) is the time interval in seconds for the AOD of the activated form of the photochromic material in the coating to reach half of the 15-minute AOD at 23°C after removal of the activating light. The fatigue test is the percentage of optical density remaining after 130 hours of accelerated fatigue testing. Table 7: Coating Hardness Results, Photochromic Performance Tests and Fatigue Example Fischer Microhardness (N / mm2) T1 / 2 to Photopic (seconds) ADO at saturation % of ADO loss CE . 9 27 86 0.92 40 CE . 10 34 71 0.91 81 Ex .11 27 71 0.91 38 Ex . 12 27 74 0 . 90 20 Ex . 13 37 80 0.86 30 Ex . 14 27 71 0.92 27 Ex . 15 37 74 0.91 16 Ex . 16 22 79 0.88 32 Ex . 17 8 67 0.91 44 The test results tabulated in Table 7 demonstrate that the photochromic curable compositions according to the present invention, which include segmented fluorinated polymer(s), provide cured photochromic layers that have an improvement in at least one of the photochromic performance properties (such as reduced Ti / 2 values, improved surface hardness, or improved fatigue of the photochromic dye) compared to comparative photochromic curable compositions without segmented polymers and comparative compositions which include segmented polymers without fluorinated components. It is hereby stated that, as of this date, the best method known to the applicant for putting the aforementioned invention into practice is the one that is clear from the present description of the invention.

Claims

CLAIMS 1. A photochromic curable composition comprising: (a) a photochromic compound; (b) a segmented polymer comprising active hydrogen groups, at least a first segment, and at least a second segment, wherein: (i) each first segment independently comprises a fluorinated polymer segment, and (ii) each second segment independently comprises a segment selected from the group consisting of a polycarbonate segment, a polyester segment, a polyether segment, a polyurethane segment, and a segment of copolymers thereof; and (c) a curing agent comprising reactive functional groups that are reactive with the active hydrogen groups of the segmented polymer, wherein the curing agent comprises at least one of a polyisocyanate, a polyisothiocyanate, or an aminoplast.

2. The photochromic curable composition according to claim 1, wherein at least a portion of each second segment (ii) is terminated with a group derived from a compound containing active hydrogen.

3. The photochromic curable composition according to claim 1 or 2, wherein: the segmented polymer (b) has an active hydrogen equivalent weight of from 1,000 to 15,000 g / eq, and each active hydrogen group of the segmented polymer (b) is independently selected from the group consisting of hydroxyl groups, thiol groups, primary amine groups, and secondary amine groups.

4. The photochromic curable composition according to any one of claims 1 to 3, wherein each active hydrogen group of the segmented polymer (b) is hydroxyl.

5. The photochromic curable composition according to any one of claims 1 to 4, wherein at least a first segment (i) and at least a second segment (ii) are covalently linked to each other by a linking group selected from the group consisting of a carboxylic acid ester linking group, a thioester linking group, an amide linking group, a urethane linking group, a thiourethane linking group, a urea linking group, a thiourea linking group, a carbonate linking group, an ether linking group, and a thioether linking group.

6. The photochromic curable composition according to any one of claims 1 to 5, wherein the second segment (ii) is present in the segmented polymer (b) in an amount from 40 percent by weight to 95 percent by weight, based on the total weight of the segmented polymer.

7. The photochromic curable composition according to any one of claims 1 to 6, wherein the photochromic curable composition comprises a total number of second segments (ii) from 15 percent by weight to 50 percent by weight, based on the total solids weight of the photochromic curable composition.

8. The photochromic curable composition according to any one of claims 1 to 7, wherein each second segment (ii) independently comprises at least one of a polycarbonate segment, a polycarbonate-polyester segment, a polycarbonate-polyurethane segment, a polyether segment, or a polycarbonate-polyester-polyurethane segment.

9. The photochromic curable composition according to any one of claims 1 to 8, wherein: the curing agent (c) comprises at least one of a polyisocyanate comprising reactive isocyanate groups, or a polyisothiocyanate comprising reactive isothiocyanate groups, and a molar ratio of reactive functional groups of the curing agent (c) to active hydrogen groups of the segmented polymer (b) is at least 4:

1.

10. The photochromic curable composition according to any one of claims 1 to 9, wherein the molar ratio of reactive functional groups of the curing agent (c) to active hydrogen groups of the segmented polymer (b) is at least 5:1 and less than or equal to 60:

1.

11. The photochromic curable composition according to any one of claims 1 to 10, wherein the curing agent (c) comprises a polyisocyanate, comprising reactive isocyanate groups.

12. The photochromic curable composition according to claim 11, wherein the polyisocyanate is an aliphatic polyisocyanate, 13. The photochromic curable composition according to any one of claims 1 to 12, wherein the curing agent (c) comprises a polyisocyanate and at least some of the reactive isocyanate groups comprising the polyisocyanate curing agent are blocked with a blocking agent, and each blocking agent is independently selected from the group consisting of methyl ethyl ketoxime, pyrazole, and dialkylpyrazole.

14. The photochromic curable composition according to any one of claims 1 to 13, wherein the photochromic compound (a) is selected from the group consisting of naphthopyrans, benzopyrans, phenanthropyrans, indenonaphthopyrans, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)-benzoxazines, fulgides, fulgimides and mixtures of such photochromic compounds.

15. The photochromic curable composition according to any one of claims 1 to 14, wherein the fluorinated polymer segment comprises an active hydrogen group.

16. A polymeric film comprising the photochromic curable composition according to any one of claims 1 to 15.

17. An article comprising: (A) a substrate; and (B) a photochromic layer on at least one surface of the substrate, wherein the photochromic layer is formed from the curable photochromic composition according to any one of claims 1 to 15.

18. A multilayer photochromic article comprising at least one photochromic layer formed from the photochromic curable composition according to any one of claims 1 to 15.