The present invention relates to mesogen compounds that include first and second mesogens that are connected by a linking group, and which are optionally polymerizable, liquid crystal compositions that include such mesogen compounds, and to optical elements that include such mesogen compounds.

BACKGROUND

[0002] The molecules of a liquid crystal are typically capable of aligning with one another in substantially one direction, which results in a fluid material having anisotropic properties, such as with regard to optical, electromagnetic, and/or mechanical properties. A mesogen is typically described as the primary or fundamental unit (or segment or group) of a liquid crystal material that induces, and/or is induced into, structural order amongst and between liquid crystals (such as, other liquid crystal materials that are present).

[0003] Liquid crystal polymers are polymers capable of forming regions of highly ordered structure while in a liquid phase. Liquid crystal polymers have a wide range of uses, including engineering plastics, and gels for liquid crystal displays (LCD’s). The structure of liquid crystal polymers can be described as being composed of densely packed elongated polymer chains that provide self-reinforcement almost to the melting point of the polymer.

[0004] Dichroism can occur in liquid crystals, including mesogen compounds, due to the optical anisotropy of the molecular structure, or the presence of impurities, or the presence of dichroic dyes and/or photochromic-dichroic materials. As used herein, the term“dichroism” and similar terms, such as“dichroic”, means the ability to absorb one of two orthogonal plane polarized components of radiation (including transmitted and/or reflected radiation) more strongly than the other orthogonal plane polarized component. Photochromic-dichroic materials possess both photochromic properties and dichroic properties. A photochromic-dichroic material, in some instances, can be described as including a photochromic molecule (or core, or moiety) to which is covalently attached at least one lengthening group at least a portion of which is capable of being aligned with (or by) a mesogenic material.

[0005] When used in combination with liquid crystal materials, such as mesogen compounds, the dichroic properties of photochromic-dichroic compounds, such as polarization efficiency and absorption ratio, can be enhanced. While not intending to be bound by any theory, it is believed based on the evidence at hand, that alignment of the photochromic-dichroic compounds with aligned mesogen compounds enhances the dichroic properties of the photochromic-dichroic compounds, such as improved absorption ratio (AR) values.

[0006] The photochromic properties of photochromic-dichroic compounds can be enhanced by a chemical environment that allows the photochromic portion thereof to efficiently undergo a reversible conformational change between an absorbing (or colored state) and a non-absorbing (or non-colored state). Examples of quantifiable photochromic properties include, but are not limited to: fade rate (sometimes referred to as fade half-life, T1/2); change in optical density (sometimes designated as DOD); the change in optical density (DOD) at saturation; sensitivity (sometimes designated as DOD/Min); and the efficiency at which the photochromic compound absorbs radiation required to activate the photochromic compound (sometimes designated as chromaticity). The chemical environment provided by the aligned mesogen compounds, while enhancing dichroic properties of the dichroic portion of a photochromic-dichroic compound, can in some instances provide a chemical environment that restricts or limits the efficient reversible conformational change of the photochromic portion of the photochromic-dichroic compound.

[0007] It would be desirable to develop new mesogen compounds that are capable of further enhancing the dichroic properties of dichroic materials, such as photochromic-dichroic compounds. It would be further desirable that such newly developed mesogen compounds maintain or enhance the photochromic properties of photochromic-dichroic materials used in conjunction therewith.

SUMMARY

[0008] In accordance with the present invention, there is provided a mesogen-containing compound represented by the following Formula (I),

With reference to Formula (I),

(A) Mesogen-1 is represented by the following Formula (II),

With reference to Formula (II),

R is selected from hydrogen, alkyl, and alkoxy; and

e’ and f for each occurrence for Formula (II), are independently from 0 to 4, provided the sum of e’ and f' is at least 2.

With further reference to Formula (I),

(B) Mesogen-2 is represented by Formula (II) of Mesogen-1, or the following Formula (III),

With reference to Formula (III),

P is selected from R, acrylate, methacrylate, trihalomethacrylate, oxirane, hydroxyl, amino, carboxylic acid, and carboxylic acid ester;

d is 0 to 20;

Si independently for each d is selected from an Si-spacer unit chosen from: -(CH2)-; -O-; -C(O)-; and -NH-, provided that when two Si-spacer units comprising heteroatoms are linked together, the Si-spacer units are linked so that heteroatoms are not directly linked to each other;

Q1 is a divalent group selected from the group consisting of: unsubstituted or substituted cycloaliphatic group; unsubstituted or substituted heterocycloaliphatic group; unsubstituted or substituted aryl; and unsubstituted or substituted heteroaryl; wherein the cycloaliphatic group substituents, heterocycloaliphatic group substituents, aryl substituents, and heteroaryl substituents are each independently selected from alkyl and halogen; and

e” and f” for each occurrence for Formula (III), are independently from 0 to 6, provided the sum of e” and f’ is at least 2.

Independently for each of Formula (II) and Formula (III),

(i) Q2 and Q3 for each occurrence, are independently a divalent group selected from the group consisting of: unsubstituted or substituted cycloaliphatic group; unsubstituted or substituted heterocycloaliphatic group; unsubstituted or substituted aryl; and unsubstituted or substituted heteroaryl; wherein the cycloaliphatic group substituents, heterocycloaliphatic group substituents, aryl substituents, and heteroaryl substituents are each independently selected from alkyl and halogen;

(ii) S2, S3, and S4 for each occurrence, are independently selected from a spacer unit chosen from: -(CH2)-; -O-; -C(O)-; and -NH-; and

(iii) e, f, and g for each occurrence, are independently 0 to 3, provided that when two spacer units comprising heteroatoms are linked together the spacer units are linked so that heteroatoms are not directly linked to each other.

With additional reference to Formula (I),

(C) -L- is represented by the following Formula (IV),

With reference to Formula (IV),

(i) y is 1 to 30;

(ii) each A independently for each y is a divalent group selected from the group consisting of aliphatic group and haloaliphatic group;

(iii) each B independently for each y is a divalent group selected from the group consisting of: -O-; -C(O)O-; -0C(O)O-; -C(O)N(R1)- where Ri is H or alkyl;

-NH-C(O)O-; -N(R2)C(O)N(R2)- where each R2 is independently selected from H or alkyl;

where n is 1 to 5, and each R3 independently for each n is selected from methyl, ethyl, and phenyl; -Si(R4)(R4)- where each R4 is independently selected from methyl, ethyl, and phenyl; unsubstituted or substituted cycloaliphatic groups; unsubstituted or substituted aryl; and unsubstituted or substituted -O-(Aryl)-O-; wherein the cycloaliphatic substituents, the aryl substituents, and -O-(Aryl)-O- substituents are each independently selected from alkyl, and -(S1)d-P, where Si, d and P are each as defined with regard to Formula (III); and

(iv) E is a divalent group selected from the group consisting of aliphatic group and haloaliphatic group.

[0009] In further accordance with the present invention, there is provided liquid crystal compositions that include the mesogen-containing compound of the present invention, such as described with reference to Formula (I).

[0010] There is provided, in further accordance with the present invention, an optical element that comprises: a substrate; and a layer on at least a portion of a surface of the substrate, in which the layer comprises the mesogen-containing compound of the present invention, such as described with reference to Formula (I).

[0011] The features that characterize the present invention are pointed out with particularity in the claims, which are annexed to and form a part of this disclosure. These and other features of the invention, its operating advantages and the specific objects obtained by its use will be more fully understood from the following detailed description in which non-limiting embodiments of the invention are illustrated and described.

DETAILED DESCRIPTION

[0012] As used herein, the articles“a”,“an”, and“the” include plural referents unless otherwise expressly and unequivocally limited to one referent.

[0013] Unless otherwise indicated, all ranges or ratios disclosed herein are to be understood to encompass any and all subranges or subratios subsumed therein. For example, a stated range or ratio of“1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges or subratios beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less, such as but not limited to, 1 to 6.1, 3.5 to 7.8, and 5.5 to 10.

[0014] As used herein, unless otherwise indicated, left-to-right representations of linking groups, such as divalent linking groups, are inclusive of other appropriate orientations, such as, but not limited to, right-to-left orientations. For purposes of non-limiting illustration, the left-to-

right representation of the divalent linking group
or equivalently -C(O)O-

or -(O)CO-, is inclusive of the right-to-left representation thereof,
or equivalently -OC(O)- or -0(O)C-.

[0015] Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as modified in all instances by the term“about”.

[0016] As used herein, 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.

[0017] As used herein, polydispersity index (PDI) values represent a ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the polymer (i.e., Mw/Mn).

[0018] As used herein, the term“polymer” means homopolymers (such as prepared from a single monomer species), copolymers (such as prepared from at least two monomer species), and graft polymers (including, but not limited to, star polymers and comb polymer).

[0019] 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.

[0020] 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 absorption of at least actinic radiation. Further, as used herein, the term“photochromic material” means any substance that is adapted to display photochromic properties (such as adapted to have an absorption spectrum for at least visible radiation that varies in response to absorption of at least actinic radiation) and which includes at least one photochromic compound.

[0021] As used herein, the term“actinic radiation” means electromagnetic radiation that is capable of causing a response in a material, such as, but not limited to, transforming a photochromic material from one form or state to another as discussed in further detail herein.

[0022] As used herein, the term“photochromic material” includes thermally reversible photochromic materials and compounds and non-thermally reversible photochromic materials and compounds. The term“thermally reversible photochromic compounds/materials” as used herein means compounds/materials capable of converting from a first state (such as a“clear state”) to a second state (such as a“colored state”) in response to actinic radiation, and reverting back to the first state in response to thermal energy. The term“non-thermally reversible photochromic compounds/materials” as used herein means compounds/materials capable of converting from a first state (such as a“clear state”) to a second state (such as a“colored state”) in response to actinic radiation, and reverting back to the first state in response to actinic radiation of substantially the same wavelength(s) as the absorption(s) of the colored state.

[0023] 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 instead refer to two different conditions or properties. For purposes of non-limiting illustration, the first state and the second state of a photochromic compound can differ with respect to at least one optical property, such as but not limited to the absorption of visible and/or UV radiation. Thus, according to various non-limiting embodiments disclosed herein, the photochromic compounds used in conjunction with the present invention can have a different absorption spectrum in each of the first and second state. For example, while not limiting herein, a photochromic compound used in conjunction with the present invention can be clear in the first state and colored in the second state. Alternatively, a photochromic compound used in conjunction with the present invention can have a first color in the first state and a second color in the second state. Additionally, a photochromic-dichroic compound used in conjunction with the present invention can have a first alignment in a first state, and a second alignment in a second state, in which one of the first alignment and second alignment is substantially non-aligned.

[0024] 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 or element or device can be chosen from ophthalmic articles, elements and devices, display articles, elements and devices, windows, mirrors, and active and passive liquid crystal cell articles, elements and devices.

[0025] As used herein, the term“ophthalmic” means pertaining to or associated with the eye and vision. Non-limiting examples of ophthalmic articles or elements include corrective and non-corrective lenses, including single vision or multi-vision lenses, which can be either segmented or non-segmented multi-vision lenses (such as, but not limited to, bifocal lenses, trifocal lenses, and progressive lenses), as well as other elements used to correct, protect, or

enhance (cosmetically or otherwise) vision, including, without limitation, contact lenses, intra ocular lenses, magnifying lenses, and protective lenses or visors.

[0026] 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 elements, such as security marks.

[0027] As used herein, the term“window” means an aperture adapted to permit the transmission of radiation there-through. Non-limiting examples of windows include automotive, marine, rail, and aircraft transparencies; windshields; filters; shutters; and optical switches.

[0028] As used herein, the term“mirror” means a surface that specularly reflects a large fraction of incident light.

[0029] As used herein, the term“liquid crystal cell” refers to a structure containing a liquid crystal material that is capable of being ordered. A non-limiting example of a liquid crystal cell element is a liquid crystal display.

[0030] As used herein, the terms“formed over”,“deposited over”, ‘provided over”,

“applied over”,“residing over”, or“positioned over”, mean formed, deposited, provided, applied, residing, or positioned on but not necessarily in direct (or abutting) contact with the underlying element, or surface of the underlying element. For example, a layer“positioned over” a substrate does not preclude the presence of one or more other layers, coatings, or films of the same or different composition located between the positioned or formed layer and the substrate.

[0031] All documents, such as but not limited to issued patents and patent applications, referred to herein, and unless otherwise indicated, are to be considered to be“incorporated by reference” in their entirety.

[0032] As used herein, the term“aliphatic” and related terms, such as“aliphatic group(s)”, means non-cyclic and non-aromatic hydrocarbon groups, which include at least one carbon atom, such as 1 to 20 carbon atoms, such as C1-C20 aliphatic groups, or C1-C10 aliphatic groups, or C1-C6 aliphatic groups; can be linear or branched; optionally include one or more interior and/or terminal alkene (or alkenyl) groups; and optionally include one or more interior and/or terminal alkyne (or alkynyl) groups. When including two or more alkene groups, the alkene groups of an aliphatic group can be conjugated and/or non-conjugated. When including two or more alkyne groups, the alkyne groups of an aliphatic group can be conjugated and/or non-conjugated. When including at least one alkene group and at least one alkyne group, the alkene and alkyne groups of the aliphatic group can be conjugated and/or non-conjugated relative to each other.

[0033] Examples of aliphatic groups include, but are not limited to, alkyl groups. As used herein, the term“alkyl” and related terms, such as“alkyl group(s)”, means groups which include at least one carbon atom, such as 1 to 20 carbon atoms, such as C1-C20 alkyl groups, or C1-C10 alkyl groups, or C1-C6 alkyl groups; are linear or branched; and are saturated (and correspondingly are free of alkene groups and alkyne groups). Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, t-butyl, linear or branched pentyl, linear or branched hexyl, linear or branched heptyl, linear or branched octyl, linear or branched nonyl, linear or branched decyl, linear or branched undencyl, linear or branched dodecyl, linear or branched tridecyl, linear or branched tetradecyl, linear or branched pentadecyl, linear or branched hexadecyl, linear or branched heptadecyl, linear or branched octadecyl, linear or branched nonadecyl, and linear or branched eicosanyl.

[0034] As used herein, recitations of“linear or branched” groups, such as, but not limited to, linear or branched alkyl, are herein understood to include, for purposes of no-limiting illustration, 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, but not limited to, branched C3-C20 alkyl groups.

[0035] Examples of aliphatic groups include, but are not limited to, alkenyl groups. As used herein, the term“alkenyl” and related terms, such as“alkenyl groups”, means groups which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 alkenyl groups, or C2-C10 alkenyl groups, or C2-C6 alkenyl groups; are linear or branched; and include one or more interior and/or terminal alkene (or alkenyl) groups. Examples of alkenyl groups include, but are not limited to, those examples of linear or branched alkyl groups recited previously herein, which have at least two carbon atoms and at least one alkene (or alkenyl) group, such as, but not limited to, ethenyl, linear or branched propenyl, linear or branched butenyl, linear or branched pentenyl, linear or branched hexencyl, etc.

[0036] Examples of aliphatic groups include, but are not limited to, alkynyl groups. As used herein, the term“alkynyl” and related terms, such as“alkynyl group(s)”, means groups which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 alkynyl groups, or C2-C10 alkynyl groups, or C2-C6 alkynyl groups; are linear or branched; and include one or more

interior and/or terminal alkyne (or alkynyl) groups. Examples of alkynyl groups include, but are not limited to, those examples of linear or branched alkyl groups recited previously herein, which have at least two carbon atoms and at least one alkyne (or alkynyl) group, such as, but not limited to, ethynyl, propynyl, linear or branched butynyl, linear or branched pentynyl, linear or branched hexynyl, etc.

[0037] As used herein, the term“haloaliphatic” and related terms, such as“haloaliphatic group(s)”, means non-cyclic and non-aromatic hydrocarbon groups, which include at least one carbon atom, such as 1 to 20 carbon atoms, such as C1-C20 haloaliphatic groups, or C1-C10 haloaliphatic groups, or C1-C6 haloaliphatic groups; include at least one halo group selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I); are linear or branched; optionally include one or more interior and/or terminal alkene groups; and optionally include one or more interior and/or terminal alkyne groups. When including two or more alkene groups, the alkene groups of an haloaliphatic group can be conjugated and/or non-conjugated. When including two or more alkyne groups, the alkyne groups of an haloaliphatic group can be conjugated and/or non-conjugated. When including at least one alkene group and at least one alkyne group, the alkene and alkyne groups of the haloaliphatic group can be conjugated and/or non-conjugated relative to each other. At least one available hydrogen of, and up to all available hydrogens of, a haloaliphatic group can be replaced with a halo group, such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I). Correspondingly, as used herein, the term“haloaliphatic” includes, but is not limited to, “perhaloaliphatic” and related terms, such as“perhaloaliphatic group(s)”.

[0038] Examples of haloaliphatic groups include, but are not limited to, haloalkyl groups.

As used herein, the term“haloalkyl” and related terms, such as“haloalkyl group(s)”, means groups which include at least one carbon atom, such as 1 to 20 carbon atoms, such as C1-C20 haloalkyl, or C1-C10 haloalkyl, or C1-C6 haloalkyl; are linear or branched; include at least one halo group, such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I); and are saturated (and correspondingly are free of alkene groups and alkyne groups). At least one available hydrogen of, and up to all available hydrogens of, a haloalkyl group can be replaced with a halo group, such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I). Correspondingly, as used herein, the term“haloalkyl” includes, but is not limited to,“perhaloalkyl” and related terms, such as “perhaloalkyl group(s)”. Examples of haloalkyl groups include, but are not limited to, those examples of linear or branched alkyl groups recited above, which include at least one halo group, such as, but not limited to, halomethyl, haloethyl, linear or branched halopropyl, linear or branched halobutyl, linear or branched halopentyl, linear or branched halohexyl, etc., each independently including at least one halo group.

[0039] Examples of haloaliphatic groups include, but are not limited to, haloalkenyl groups. As used herein, the term“haloalkenyl” and related terms, such as“haloalkenyl group(s)”, means groups which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 haloalkenyl, or C2-C10 haloalkenyl, or C2-C6 haloalkenyl; are linear or branched; include at least one halo group, such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I); and include one or more interior and/or terminal alkene (or alkenyl) groups. Examples of haloalkenyl groups include, but are not limited to, those examples of linear or branched alkyl groups recited above, which have at least two carbon atoms, at least one alkene (or alkenyl) group, and at least one halo group, such as, but not limited to, haloethenyl, linear or branched halopropenyl, linear or branched halobutenyl, linear or branched halopentenyl, linear or branched halohexenyl, etc., each independently including at least one halo group.

[0040] Examples of haloaliphatic groups include, but are not limited to, haloalkynyl groups. As used herein, the term“haloalkynyl” and related terms, such as“haloalkynyl group(s)”, means groups which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 haloalkynyl, or C2-C10 haloalkynyl, or C2-C6 haloalkynyl; are linear or branched; include at least one halo group (or halogen group), such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I); and include one or more interior and/or terminal alkyne (or alkynyl) groups. Examples of haloalkynyl groups include, but are not limited to, those examples of linear or branched alkyl groups recited above, which have at least two carbon atoms, at least one alkyne (or alkynyl) group, and at least one halo group, such as, but not limited to, haloethynyl, halopropynyl, linear or branched halobutynyl, linear or branched halopentynyl, linear or branched halohexynyl, etc., each independently including at least one halo group.

[0041] As used herein, the term“cycloaliphatic” and related terms, such as“cycloaliphatic group(s)”, means cyclic and non-aromatic hydrocarbon groups, which include at least three carbon atoms, such as 3 to 20 carbon atoms, such as C3-C20 cycloaliphatic groups, or C3-C10 cycloaliphatic groups, or C3-C8 cycloaliphatic groups; optionally include at least one unsaturated group selected from alkene and/or alkyne; and optionally include two or more fused cycloaliphatic rings.

[0042] Examples of cycloaliphatic groups include, but are not limited to, cycloalkyl groups. As used herein, the term“cycloalkyl” and related terms, such as“cycloalkyl group(s)”, means groups which include at least three carbon atoms, such as 3 to 20 carbon atoms, such as C3-C20 cycloalkyl groups, or C3-C10 cycloalkyl groups, or C3-C8 cycloalkyl groups; optionally include at least one unsaturated group selected from alkene and/or alkyne; and optionally include two or more fused cycloalkyl rings. Examples of cycloalkyl groups include, but are not limited to, cyclopropyl; cyclobutyl; cyclopentyl; cyclohexyl; cycloheptyl; cyclooctyl; cyclononyl; cyclodecyl; cycloundecyl; cyclododecyl; bicyclo[2.2.1]heptanyl; decahydronaphthalenyl; tetradecahydroanthracenyl; tetradecahydrophenanthrenyl; and dodecahydro-lH-phenalenyl.

[0043] As used herein, the term “heterocycloaliphatic” and related terms, such as

“heterocycloaliphatic group(s)”, means cyclic and non-aromatic groups, which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 heterocycloaliphatic groups, or C2-C10 heterocycloaliphatic groups, or C2-C8 heterocycloaliphatic groups; and which have at least one hetero atom in the cyclic ring, such as, but not limited to, O, S, N, P, and combinations thereof; optionally include at least one unsaturated group selected from alkene and/or alkyne; and optionally include two or more fused non-aromatic cyclic rings, at least one of which is a fused heterocycloaliphatic ring.

[0044] Examples of heterocycloaliphatic groups include, but are not limited to, heterocycloalkyl groups. As used herein, the term“heterocycloalkyl” and related terms, such as “heterocycloalkyl group(s)”, means groups which include at least two carbon atoms, such as 2 to 20 carbon atoms, such as C2-C20 heterocycloalkyl groups, or C2-C10 heterocycloalkyl groups, or C2-C8 heterocycloalkyl groups; and which have at least one hetero atom in the cyclic ring, such as, but not limited to, O, S, N, P, and combinations thereof; optionally include at least one unsaturated group selected from alkene and/or alkyne; and optionally include two or more fused non-aromatic cyclic rings, at least one of which is a fused heterocycloalkyl ring. Examples of heterocycloalkyl groups include, but are not limited to, imidazolyl, tetrahydrofuranyl, tetrahydropyranyl, piperidinyl, piperazinyl, morpholinyl, 7-oxabicyclo[2.2.1]heptanyl, octahydrocyclopenta[b]pyranyl, and octahydro-lH-isochromenyl.

[0045] As used herein, the term“aryl” and related terms, such as“aryl group(s)”, means cyclic aromatic hydrocarbon groups, which include at least 5 carbon atoms, such as C5-C20 aryl groups, or C5-C14 aryl groups; and optionally include at least two fused aromatic rings. Examples of aryl groups include, but are not limited to, phenyl, naphthalenyl, anthracenyl, phenanthrenyl, triphenylenyl, 9,10-dihydroanthracenyl, 9,10-dihydrophenanthrenyl, and triptycenyl.

[0046] As used herein, the term“heteroaryl” and related terms, such as“heteroaryl group(s)”, means cyclic aromatic hydrocarbon groups, which include at least 3 carbon atoms, such as C3-C20 heteroaryl groups, or C5-C14 heteroaryl groups; at least one heteroatom in the aromatic ring, such as -O-, -N-, and/or -S-; and optionally include at least two fused aromatic rings, at least one of which is a fused heteroaryl ring. Examples of hetroaryl groups include, but are not limited to, pyrazolyl, imidazolyl, triazinyl, furanyl, thiophenyl, pyranyl, pyridinyl, isoquinolinyl, and pyrimidinyl.

[0047] As used herein, the term“alkoxy” and related terms, such as“alkoxy group(s)”, means an alkyl group which includes at least one carbon atom, such as 1 to 20 carbon atoms, such as C1-C20 alkoxy, or C1-C10 alkoxy, or C1-C6 alkoxy. Examples of alkoxy groups include, but are not limited to, those examples of alkyl groups recited previously herein, which include a terminal divalent oxygen linkage or group (or terminal ether linkage or group), such as, but not limited to, methoxy (CH3-O-), ethoxy (CH3CH2-O-), n-propoxy (CH3CH2CH2-O-), iso-propoxy, linear or branched butoxy, linear or branched pentoxy, linear or branched hexoxy, etc.

[0048] As used herein, the term“amino” and related terms, such as“amino group”, includes groups represented by -N(R11)(R12), where R11 and R12 are each independently selected, for example, from hydrogen, aliphatic groups, cycloaliphatic groups, heterocycloaliphatic groups, aryl groups, and heteroaryl groups.

[0049] As used herein, the term“halogen” and related terms, such as“halogen group(s)” and/or“halo group(s)”, means a single bonded halogen atom, such as selected from fluoro (F), chloro (Cl), bromo (Br), and/or iodo (I).

[0050] As used herein, and unless otherwise explicitly stated, the term“hydrogen” and related terms, such as“hydrogen group(s)”, means a single bonded hydrogen (-H).

[0051] With reference to Formula (II), and with some embodiments, R is selected from hydrogen, alkyl, and alkoxy. With further reference to Formula (II), and in accordance with some further embodiments, R is selected from hydrogen and alkyl. The alkyl and alkoxy groups from which R of Formula (II) can be selected include, but are not limited to, those classes and examples of alkyl and alkoxy groups described previously herein. With some embodiments, R of Formula (II) is selected from hydrogen, methyl, ethyl, n-propyl, i-propyl, linear or branched butyl, linear or branched pentyl, linear or branched hexyl, methoxy, ethoxy, n-propoxy, i-propoxy, linear or branched butoxy, linear or branched pentoxy, and linear or branched hexoxy.

[0052] With some embodiments, e’ and f' for each occurrence for Formula (II) are independently from 0 to 4 (such as 0, 1, 2, 3, or 4, and combinations thereof); provided the sum of e’ and f' is at least 2, such as from 2 to 8, or 2 to 5, or 2 to 4.

[0053] With reference to Formula (III), and in accordance with some embodiments, P is selected from R, as described with regard to Formula (II); acrylate (CH2=CHC(O)O-), methacrylate (CH2=C(CH3)C(O)O-); trihalomethacrylate (CH2=C(CX3)C(O)O- where each X

independently is a halogen or halo group); oxirane
hydroxyl (-OH); amino; carboxylic acid (-C(O)OH); and carboxylic acid ester (-C(O)OR’, where R’ is selected from aliphatic group, cycloaliphatic group, aryl, and heteroaryl). Examples of trihalomethacrylate from which P can be selected include, but are not limited to, trifluoromethacrylate and tri chi or om ethacry 1 ate .

[0054] In accordance with some embodiments, and with reference to Formula (III), subscript d is 0 to 20, or 0 to 15, or 0 to 12, or 0 to 10, or 0 to 8, or 0 to 5.

[0055] With further reference to Formula (III), Si independently for each d is selected from an Si-spacer unit chosen from -(CH2)-; -O-; -C(O)-; and -NH-, provided that when two Si-spacer units including heteroatoms are linked together, the Si-spacer units are linked so that heteroatoms are not directly linked to each other. Adjacent Si-spacer units can together form various divalent linkages, such as, but not limited to, alkyl linkages; ether linkages; ester (or carboxylate) linkages, -O-C(O)- and/or -C(O)-O-; carbonate linkages, -O-C(O)-O-; amide linkages, -NH-C(O)-and/or -C(O)-NH-; urea linkages, -NH-C(O)-NH-; carbamate linkages, -O-C(O)-NH- and/or -NH-C(O)-O-; dione linkages, -C(O)-C(O)-; and combinations thereof, provided that the Si-spacer units are linked so that heteroatoms are not directly linked to each other. With some embodiments, Si-spacer units being linked so that heteroatoms are not directly linked to each other, means that -(Si)d- is free of: -O- bonded directly to -O-; -NH- bonded directly to -NH-; and -O- and -NH-bonded directly to each other.

[0056] With some embodiments, e” and f” for each occurrence for Formula (III), are independently from 0 to 6 (such as 0, 1, 2, 3, 4, 5, or 6, and combinations thereof), provided the sum of e” and f” is at least 2, such as from 2 to 10, or 2 to 5, or 2 to 4.

[0057] Independently for each of Formula (II) and Formula (III), and in accordance with some embodiments, S2, S3, and S4 for each occurrence are independently selected from a spacer unit chosen from -(CH2)-, -O-, -C(O)-, and -NH-; subscripts e, f, and g for each occurrence are independently 0 to 3 (such as 0, 1, 2, or 3); provided that when two spacer units including heteroatoms are linked together the spacer units are linked so that heteroatoms are not directly linked to each other. Adjacent spacer units from which each of S2, S3, and S4 are each independently selected can together form various linkages (such as, but not limited to, divalent linkages), such as, but not limited to, alkyl linkages; ether linkages; ester (or carboxylate) linkages, -O-C(O)- and/or -C(O)-O-; carbonate linkages, -O-C(O)-O-; amide linkages, -NH-C(O)-and/or -C(O)-NH-; urea linkages, -NH-C(O)-NH-; carbamate linkages, -O-C(O)-NH- and/or -NH-C(O)-O-; dione linkages, -C(O)-C(O)-; and combinations thereof, provided that the spacer units are linked so that heteroatoms are not directly linked to each other. With some embodiments, spacer units (from which each of S2, S3, and S4 are each independently selected) being linked so that heteroatoms are not directly linked to each other, means that such combinations of adjacent spacer units are free of -O- bonded directly to -O-; -NH- bonded directly to -NH-; and -O- and -NH- bonded directly to each other.

[0058] With reference to Formula (III) and in accordance with some embodiments of the present invention, Q1 is a divalent group selected from unsubstituted or substituted cycloalkyl; unsubstituted or substituted phenyl; unsubstituted or substituted naphthyl; and unsubstituted or substituted triptycenyl; in which the cycloalkyl substituents, phenyl substituents, naphthyl substituents, and triptycenyl substituents, are each independently selected from alkyl and halogen, where the alkyl groups and halogen groups are each selected from those classes and examples as described previously herein. With further embodiments, and independently for each of Formula (II) and Formula (III), Q2 and Q3 for each occurrence are independently a divalent group selected from unsubstituted or substituted cycloalkyl; unsubstituted or substituted phenyl; unsubstituted or substituted naphthyl; and unsubstituted or substituted triptycenyl; in which the cycloalkyl substituents, phenyl substituents, naphthyl substituents, and triptycenyl substituents, are each independently selected from alkyl and halogen, where the alkyl groups and halogen groups are each selected from those classes and examples as described previously herein.

[0059] With reference to Formula (III) and in accordance with some additional embodiments of the present invention, Q1 is a divalent group selected from unsubstituted or

substituted 1,4-cyclohexyl; unsubstituted or substituted 1,4-phenyl; unsubstituted or substituted 1,5-naphthyl; unsubstituted or substituted 2,6-naphthyl; unsubstituted or substituted 1,8-naphthyl; and unsubstituted or substituted 1,4-triptycenyl, in which the 1,4-cyclohexyl substituents, 1,4-phenyl substituents, 1,5-naphthyl substituents, 2,6-naphthyl substituents, 1,8-naphthyl substituents, and 1,4-triptycenyl substituents, are each independently selected from alkyl and halogen, where the alkyl groups and halogen groups are each selected from those classes and examples as described previously herein. With some further embodiments, and independently for each of Formula (II) and Formula (III), Q2 and Q3 for each occurrence are independently a divalent group selected from the group consisting of unsubstituted or substituted 1,4-cyclohexyl; unsubstituted or substituted 1,4-phenyl; unsubstituted or substituted 1,5-naphthyl; unsubstituted or substituted 2,6-naphthyl; unsubstituted or substituted 1,8-naphthyl; and unsubstituted or substituted 1,4-triptycenyl, wherein the 1,4-cycloalkyl substituents, 1,4-phenyl substituents, 1,5-naphthyl substituents, 2,6-naphthyl substituents, 1,8-naphthyl substituents, and 1,4-triptycenyl substituents, are each independently selected from alkyl and halogen, where the alkyl groups and halogen groups are each selected from those classes and examples as described previously herein.

[0060] With some embodiments of the mesogen-containing compounds of the present invention, and with reference to Formula (I), Mesogen-2 is represented by Formula (II) of Mesogen-1.

[0061] With some further embodiments of the mesogen-containing compounds of the present invention, and with reference to Formula (I), Mesogen-2 is represented by Formula (II) of Mesogen-1, and Mesogen-1 and Mesogen-2 are the same.

[0062] With reference to Formula (I), and with some embodiments, -L- is represented by

Formula (IV) provided previously herein in which y is from 1 to 30, or 2 to 20; and in which each A independently for each y is a divalent group selected from an aliphatic group and a haloaliphatic group. With some further embodiments, and with reference to Formula (I), -L- is represented by Formula (IV) provided previously herein, in which each A independently for each y is a divalent group selected from alkyl groups and haloalkyl groups, in which the alkyl groups and haloalkyl groups are each selected from those classes and examples of alkyl groups and haloalkyl groups described previously herein.

With further reference to Formula (IV), and in accordance with some further embodiments, B independently for each y is a divalent group selected from -O-; -C(O)O-; -0C(O)O-; -C(O)N(Ri)- where Ri is H or alkyl; -NH-C(O)O-; -N(R2)C(O)N(R2)- where each R2 is independently selected

from H or alkyl;
where n is 1 to 5, and each R3 independently for each n is selected from methyl, ethyl, and phenyl; -Si(R4)(R4)- where each R4 is independently selected from methyl, ethyl, and phenyl; unsubstituted or substituted cycloalkyl (such as, but not limited to, cyclohexyl); unsubstituted or substituted phenyl; and unsubstituted or substituted -O-(Phenyl)-O-; in which the cycloalkyl substituents, the phenyl substituents, and -O-(Phenyl)-O- substituents are each independently selected from alkyl, and -(Si)d-P, where Si, d and P are each as described with regard to Formula (III). The alkyl groups from which each of R2, R3, and R4, and the various substituents can be independently selected include, but are not limited to, those classes and examples of alkyl groups described previously herein.

[0063] With further reference to Formula (IV), E is a divalent group selected from the group consisting of aliphatic groups and haloaliphatic groups. With additional reference to Formula (IV), and with some embodiments, E is a divalent group selected from alkyl groups and haloalkyl groups, in which the alkyl groups and haloalkyl groups are each selected from those classes and examples of alkyl groups and haloalkyl groups described previously herein.

[0064] With some embodiments, and with reference to Formula (IV), no B is a divalent group selected from, unsubstituted or substituted cycloaliphatic groups, unsubstituted or substituted aryl, and unsubstituted or substituted -O-(Aryl)-O-; or only one B is a divalent group selected from, unsubstituted or substituted cycloaliphatic groups, unsubstituted or substituted aryl, and unsubstituted or substituted -O-(Aryl)-O-.

[0065] With some further embodiments, and with further reference to Formula (IV), no B is a divalent group selected from, unsubstituted or substituted cycloalkyl (such as, but not limited to, unsubstituted or substituted cyclohexyl), unsubstituted or substituted phenyl, unsubstituted or substituted naphthyl, and unsubstituted or substituted -O-(Phenyl)-O-; or only one B is a divalent group selected from, unsubstituted or substituted cycloalkyl (such as, but not limited to, unsubstituted or substituted cyclohexyl), unsubstituted or substituted phenyl, unsubstituted or substituted naphthyl, and unsubstituted or substituted -O-(Phenyl)-O-.

[0066] As used herein, recitations of“-O-(Aryl)-O-” means an aryl group that includes two -O- linking groups, and which can be represented by the following Formula (V),

With reference to Formula (V), and correspondingly -O-(Aryl)-O-, the aryl group (or portion, or ring) can be selected from those classes and examples of aryl groups as described previously herein.

[0067] As used herein, recitations of -O-(Phenyl)-O- means a phenyl group that includes two -O- linking groups, and which can be represented by the following Formula (VI),

[0068] With reference to Formula (I), and in accordance with some embodiments, -L- includes at least 20 bonds, such as 20 to 200 bonds (or 30 to 200 bonds), or 20 to 150 bonds (or 30 to 150 bonds), or 30 to 140 bonds (or 40 to 140 bonds), or 30 to 130 bonds (or 40 to 130 bonds), or 40 to 120 bonds (or 50 to 120 bonds), or 50 to 110 bonds, where each bond is independently selected from a single bond, a double bond, and a triple bond.

[0069] With some embodiments, the linking group -L-, that links Mesogen-1 and

Mesogen-2 together, is itself free of mesogen properties (the linking group -L- is non-mesogenic).

[0070] In accordance with some embodiments, -L- of Formula (I) is selected from the following Formulas L(l) through L(23), including combinations of two or more thereof:

WHAT IS CLAIMED IS:

1. A mesogen-containing compound represented by the following Formula (I),

wherein:

(A) Mesogen-1 is represented by the following Formula (II),

wherein:

R is selected from hydrogen, alkyl, and alkoxy; and

e’ and f' for each occurrence for Formula (II) are independently from 0 to 4, provided the sum of e’ and f' is at least 2;

(B) Mesogen-2 is represented by Formula (II) of Mesogen-1, or the following Formula

(III),

wherein:

P is selected from R, acrylate, methacrylate, trihalomethacrylate, oxirane, hydroxyl, amino, carboxylic acid, and carboxylic acid ester;

d is 0 to 20;

Si independently for each d is selected from an Si-spacer unit chosen from -(CH2)-; -O-; -C(O)-; and -NH-, provided that when two Si-spacer units comprising heteroatoms are linked together, the Si-spacer units are linked so that heteroatoms are not directly linked to each other;

Q1 is a divalent group selected from the group consisting of unsubstituted or substituted cycloaliphatic group; unsubstituted or substituted heterocycloaliphatic group; unsubstituted or substituted aryl; and unsubstituted or substituted heteroaryl; wherein the cycloaliphatic group substituents, heterocycloaliphatic group substituents, aryl substituents, and heteroaryl substituents are each independently selected from alkyl and halogen; and

e” and f” for each occurrence for Formula (III) are independently from 0 to 6, provided the sum of e” and f’ is at least 2;

wherein independently for each of Formula (II) and Formula (III),

(i) Q2 and Q3 for each occurrence are independently a divalent group selected from the group consisting of unsubstituted or substituted cycloaliphatic group; unsubstituted or substituted heterocycloaliphatic group; unsubstituted or substituted aryl; and unsubstituted or substituted heteroaryl; wherein the cycloaliphatic group substituents, heterocycloaliphatic group substituents, aryl substituents, and heteroaryl substituents are each independently selected from alkyl and halogen;

(ii) S2, S3, and S4 for each occurrence are independently selected from a spacer unit chosen from -(CH2)-; -O-; -C(O)-; and -NH-; and

(iii) e, f, and g for each occurrence are independently 0 to 3, provided that when two spacer units comprising heteroatoms are linked together the spacer units are linked so that heteroatoms are not directly linked to each other;

(C) -L- is represented by the following Formula (IV),

wherein:

(i) y is 1 to 30;

(ii) each A independently for each y is a divalent group selected from the group consisting of aliphatic group and haloaliphatic group;

(iii) each B independently for each y is a divalent group selected from the group consisting of -O-; -C(O)O-; -0C(O)O-; -C(O)N(R1)- where R1 is H or alkyl;

-NH-C(O)O-; -N(R2)C(O)N(R2)- where each R2 is independently selected from H or alkyl;

where n is 1 to 5, and each R3 independently for each n is selected from methyl, ethyl, and phenyl; -Si(R4)(R4)- where each R4 is independently selected from methyl, ethyl, and phenyl; unsubstituted or substituted cycloaliphatic groups; unsubstituted or substituted aryl; and unsubstituted or substituted -O-(Aryl)-O-; wherein the cycloaliphatic substituents, the aryl substituents, and -O-(Aryl)-O- substituents are each independently selected from alkyl, and -(Si)d-P, where Si, d and P are each as defined with regard to Formula (III); and

(iv) E is a divalent group selected from the group consisting of aliphatic group and haloaliphatic group.

2. The mesogen-containing compound of claim 1, wherein:

(B) for Formula (III),

Q1 is a divalent group selected from the group consisting of unsubstituted or substituted cycloalkyl; unsubstituted or substituted phenyl; unsubstituted or substituted naphthyl; and unsubstituted or substituted triptycenyl; wherein the cycloalkyl substituents, phenyl substituents, naphthyl substituents, and triptycenyl substituents are each independently selected from alkyl and halogen; and

wherein independently for each of Formula (II) and Formula (III),

Q2 and Q3 for each occurrence are independently a divalent group selected from the group consisting of unsubstituted or substituted cycloalkyl; unsubstituted or substituted phenyl; unsubstituted or substituted naphthyl; and unsubstituted or substituted triptycenyl; wherein the cycloalkyl substituents, phenyl substituents, naphthyl substituents, and triptycenyl substituents are each independently selected from alkyl and halogen.

3. The mesogen-containing compound of claim 2, wherein:

for Formula (III), Q1 is a divalent group selected from the group consisting of unsubstituted or substituted 1,4-cyclohexyl; unsubstituted or substituted 1,4-phenyl; unsubstituted or substituted 1,5 -naphthyl; unsubstituted or substituted 2,6-naphthyl; unsubstituted or substituted

1.8-naphthyl; and unsubstituted or substituted 1,4-triptycenyl; wherein the 1,4-cyclohexyl substituents, 1,4-phenyl substituents, 1,5-naphthyl substituents, 2,6-naphthyl substituents,

1.8-naphthyl substituents, and 1,4-triptycenyl substituents are each independently selected from alkyl and halogen; and

independently for each of Formula (II) and Formula (III),

Q2 and Q3 for each occurrence are independently a divalent group selected from the group consisting of unsubstituted or substituted 1,4-cyclohexyl; unsubstituted or substituted 1,4-phenyl; unsubstituted or substituted 1,5-naphthyl; unsubstituted or substituted 2,6-naphthyl; unsubstituted or substituted 1,8-naphthyl; and unsubstituted or substituted 1,4-triptycenyl; wherein the 1,4-cycloalkyl substituents, 1,4-phenyl substituents, 1,5-naphtyl substituents, 2,6-naphthyl substituents, 1,8-naphthyl substituents, and 1,4-triptycenyl substituents are each independently selected from alkyl and halogen.

4. The mesogen-containing compound of claim 3, wherein:

(A) for Formula (II),

R is selected from hydrogen and alkyl;

(B) for Formula (III),

P is selected from R, acrylate, and methacrylate;

(C) for Formula (IV),

(ii) each A independently for each y is a divalent group selected from the group consisting of alkyl and haloalkyl;

(iii) each B independently for each y is a divalent group selected from the group consisting of -O-; -C(O)O-; -0C(O)O-; -C(O)N(Ri)- where Ri is H or alkyl;

-NH-C(O)O-; -N(R2)C(O)N(R2)- where each R2 is independently selected from H or alkyl;

where n is 1 to 5, and each R3 independently for each n is selected from methyl and phenyl; -Si(R4)(R4)- where each R4 is independently selected from methyl and phenyl; unsubstituted or substituted cycloalkyl; unsubstituted or substituted phenyl; and unsubstituted or substituted -O-(Phenyl)-O-; wherein the cycloalkyl substituents, the phenyl substituents, and -O-(Phenyl)-O- substituents are each independently selected from alkyl, and -(S1)d-P, where S1, d and P are each as defined with regard to Formula (III); and

(iv) E is a divalent group selected from the group consisting of alkyl groups and haloalkyl groups.

5. The mesogen-containing compound of claim 1, wherein provided that for Formula (IV), no B or only one B is a divalent group selected from the group consisting of unsubstituted or substituted cycloaliphatic groups; unsubstituted or substituted aryl; and unsubstituted or substituted -O-(Aryl)-O-.

6. The mesogen-containing compound of claim 5, wherein provided that for Formula (IV), no B or only one B is a divalent group selected from the group consisting of unsubstituted or substituted cycloalkyl groups; unsubstituted or substituted phenyl; unsubstituted or substituted naphthyl; and unsubstituted or substituted -O-(Phenyl)-O-.

7. The mesogen-containing compound of claim 1, wherein Mesogen-2 is represented by Formula (II) of Mesogen-1.

8. The mesogen-containing compound of claim 7, wherein Mesogen-1 and Mesogen-2 are the same.

9. The mesogen-containing compound of claim 1, wherein -L- comprises at least 20 bonds.

10. A liquid crystal composition comprising the mesogen-containing compound of claim 1.

11. The liquid crystal composition of claim 10, further comprising at least one of a photochromic compound, a dichroic compound, and a photochromic-dichroic compound.

12. The liquid crystal composition of claim 11, wherein said photochromic-dichroic compound comprises at least one photochromic moiety, and said photochromic compound and each photochromic moiety of said photochromic-dichroic compound are in each case independently selected from indeno-fused naphthopyrans, naphtho[l,2-b]pyrans, naphtho[2,l-b]pyrans, spirofluoroeno[l,2-b]pyrans, phenanthropyrans, quinolinopyrans, fluoroanthenopyrans, spiropyrans, benzoxazines, naphthoxazines, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(indoline)fluoranthenoxazines, spiro(indoline)quinoxazines, fulgides, fulgimides, diarylethenes, diarylalkylethenes, diarylalkenylethenes, non-thermally reversible photochromic compounds, and mixtures thereof.

13. An optical element comprising:

a substrate; and

a layer on at least a portion of a surface of said substrate, wherein said layer comprises the mesogen-containing compound of claim 1.

14. The optical element of claim 13, further comprising an alignment layer interposed between said substrate and said layer, wherein said alignment layer is at least partially alignable by exposure to at least one of a magnetic field, an electric field, linearly polarized radiation, shear force, or combinations of two or more thereof.

15. The optical element of claim 13, wherein said optical element is selected from a display element, a window, a mirror, a liquid crystal cell element, and an ophthalmic element, preferably selected from a corrective lens, a non-corrective lens, a contact lens, an intra ocular lens, a magnifying lens, a protective lens, and a visor.