Abstract: An optical component having an anti-fog coating obtainable by covalent attachment of a silane having the formula (1): RoXmSiAn to the surface of the optical component. The covalent attachment of the compound of the formula (1) to the surface of the optical component is accomplished by reacting at least one of the reactive, hydrolyzable —Si—X— groups with a suitable reactive surface group, for example, an —OH group, to form —Si—O—.

Abstract: Disclosed is an optical film that has excellent adhesion and surface hardness between the film substrate and a hard coat layer or other functional layer, has improved brittleness, is transparent, and has low moisture absorption and high heat resistance. Additionally disclosed are an antireflective film, a polarizing plate, and a display device using the same. The optical film has at least a hard coat layer or a back coat layer as a functional layer containing a resin on a film substrate, and is characterized in that said film substrate contains a thermoplastic acrylic resin (A) and a cellulose ester resin (B), with the content ratio by mass of said thermoplastic acrylic resin (A) and said cellulose ester resin (B) being in a range thermoplastic acrylic resin (A):cellulose ester resin (B)=95:5 to 50:50.

Abstract: The present invention provides a polyimide film which is both outstandingly transparent and highly heat resistance, and which can be usefully employed as a transparent electrically conductive film, a TFT substrate, a flexible printed circuit substrate, and the like.

Abstract: Certain patternable reflective films are used as masks to make other patterned articles, and one or more initial masks can be used to pattern the patternable reflective films. An exemplary patternable reflective film has an absorption characteristic suitable to, upon exposure to a radiant beam, absorptively heat a portion of the film by an amount sufficient to change a first reflective characteristic to a different second reflective characteristic. The change from the first to the second reflective characteristic is attributable to a change in birefringence of one or more layers or materials of the patternable film. In a related article, a mask is attached to such a patternable reflective film. The mask may have opaque portions and light-transmissive portions. Further, the mask may have light-transmissive portions with structures such as focusing elements and/or prismatic elements.

Abstract: The present invention relates to a method for manufacturing a photo-responsive cross-linked liquid-crystalline polymer film, containing: a process of preparing a photopolymerizable monomer solution by dissolving in a solvent a polyfunctional liquid-crystalline monomer, a monofunctional liquid-crystalline monomer, a polyfunctional photo-responsive monomer and a photopolymerization initiator; a process of forming a photopolymerizable coating by applying the photopolymerizable monomer solution to a surface of an alignment film by means of a wet coating method and performing removal of the solvent; and a process of forming a film by photopolymerizing the monomers through light irradiation of the photopolymerizable coating under a non-oxygen atmosphere.

Abstract: A zinc-oxide-based conductive stacked structure 1 includes a substrate 11 and, formed on at least one surface of the substrate, an undercoat layer 12 and a transparent conductive film 13. The transparent conductive film is formed of a plurality of transparent conductive layers formed from a zinc-oxide-based conductive material and has a carrier density of 2.0×1020 to 9.8×1020 cm?3. The zinc-oxide-based conductive stacked structure exhibits a change ratio in sheet resistivity of 50 or less, after bending of the stacked structure around a round bar having a diameter of 15 mm, with the transparent conductive film facing inward.

Abstract: Provided is a polymer film containing at least one of a compound represented by formula (1) of hydrates, solvates, or salts thereof. Y is a methine group or nitrogen atom. Qa, Qb, and Qc are a single bond or a divalent linking group. Ra, Rb, and Rc, are hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, cyano group, halogen group, or heterocyclic group. X2 is a single bond or a divalent linking group. X1 is a single bond or a predetermined divalent linking group.

Abstract: Disclosed is a copolymer that includes a repeat unit containing a flavorant-containing pendant and a salt-containing repeating unit. In addition, a comestible, a smoking composition, a smoking article, a smokeless tobacco composition and a heatable or combustible product are provided which incorporate one or more of the flavorant-containing copolymer.

Abstract: An object of the invention is to provide a method for manufacturing semiconductor devices that are flexible in which elements fabricated using a comparatively low-temperature (less than 500° C.) process are separated from a substrate. After a molybdenum film is formed over a glass substrate, a molybdenum oxide film is formed over the molybdenum film, a nonmetal inorganic film and an organic compound film are stacked over the molybdenum oxide film, and elements fabricated by a comparatively low-temperature (less than 500° C.) process are formed using existing manufacturing equipment for large glass substrates, the elements are separated from the glass substrate.

Abstract: A liquid crystal display device includes a first substrate, a second substrate facing the first substrate, and a liquid crystal layer between the first and second substrates. The liquid crystal layer includes a liquid crystal composition including an alkenyl liquid crystal and an antioxidant component including at least one selected from an antioxidant and a derivative thereof. In an embodiment, the antioxidant component is present in an amount of greater than 0 ppm and equal to or less than about 10,000 ppm relative to the total weight of the liquid crystal composition.

Abstract: Provided is an optical layered body which sufficiently suppresses generation of interference fringes and curls, can make a hard coat layer thin, and prevent an increase in production cost. Provided is an optical layered body having a hard coat layer formed on one surface of a light-transmitting substrate, wherein the hard coat layer has a surface roughness on its surface and the surface roughness satisfies the following inequalities of ?a and Kr where ?a is an average inclination angle of the uneven part and Kr is Kurtosis of the unevenness: 0.01°??a?0.10° 1?Kr?3.

Abstract: The instant invention relates to mesogenic media exhibiting a blue phase, comprising one, two or more compounds of formula I-A wherein the parameters are as specified in the text, preferably stabilised by a polymer, and their use in electro-optical light modulation elements and their respective use in displays, as well as to such displays.

Abstract: An object of the invention is to provide a polymerizable compound having small refractive index anisotropy and having high storage stability and high alignment properties when constituting a polymerizable liquid crystal composition, and provide a polymerizable liquid crystal composition containing the polymerizable compound. Further, the object is to provide a polymer produced by polymerizing the polymerizable liquid crystal composition and an optically anisotropic body including the polymer. The present invention provides a polymerizable compound represented by general formula (I), a polymerizable liquid crystal composition containing the compound as a constituent component, and further provides a polymer produced by polymerizing the polymerizable liquid crystal composition and an optically anisotropic body including the polymer.

Abstract: A method for forming a micro-optical or sub-micro-optical device is provided, including: forming a photolithographic mask on a transparent support, depositing a layer of a photosensitive material of negative polarity on the face, a so called front face, of the support which supports the mask, wherein the mask is disposed under the areas where the photosensitive material should be removed, insolating the layer of the photosensitive material through the rear face of the support, developing the photosensitive material in order to obtain walls of micron or submicron cavities, removing the mask areas located at the bottom of the cavities in order to obtain cavities without any mask material between the walls, introducing a fluid into the cavities of the device, and forming a closure layer on the walls in photosensitive material.

Abstract: Disclosed is a negative C-type retardation compensator for a liquid crystal display. The negative C-type retardation compensator for the liquid crystal display includes polyarlate having a thio group or a sulfur oxide group in a polymer main chain thereof. Accordingly, the retardation compensator has an absolute value of negative retardation that is larger in a thickness direction that a retardation compensator which includes polyarylate having no thio group or sulfur oxide group in a polymer main chain thereof even though the retardation compensator having the thio group or sulfur oxide group and the retardation compensator having no thio group or sulfur oxide group are the same as each other in thickness. Thereby, the negative C-type retardation compensator for liquid crystal displays is capable of being desirably applied to the liquid crystal displays.

Abstract: A protective film to a polarizer including a cellulose acylate and satisfying the following requirement (1) or (2): (1): The surface of the film has a pH of from 3.0 to 4.5. (2): The surface of the film has a pH of more than 4.5 and at most 6.0, and the film has a moisture permeability of at least 2800 g/m2·day.

Abstract: An object of this invention is to provide a cellulose ester film which satisfies the requirement 0.95<plasticizer content of A surface/plasticizer content of B surface<1.05, provided that A surface represents one surface of the cellulose ester film and B surface represents the other surface, has a high sound velocity of the film and is excellent in light leakage and color unevenness, and a film-forming method of this cellulose ester film. The cellulose ester film of the present invention, which contains a cellulose ester, is characterized by satisfying the requirement 0.95<plasticizer content of A surface/plasticizer content of B surface<1.05, provided that A surface represents one surface of the cellulose ester film and B surface represents the other surface, and having a sound velocity along at least one of a film transport direction and the lateral direction at 23.° C. 55% RH of 2.0-2.7 km/s.

Abstract: The present invention relates to a pressure-sensitive adhesive composition, and a polarizer and a liquid crystal display (LCD) device using the pressure-sensitive adhesive composition, and more particularly, to a pressure-sensitive adhesive composition including (A) an acrylic copolymer and (B) a liquid optically-anisotropic compound having a mesogen core in its structure. The liquid optically-anisotropic compound having a mesogen core in its structure according to the present invention has superior solubility and compatibility with pressure-sensitive adhesive resin, and thus the pressure-sensitive adhesive composition including the liquid optically-anisotropic compound can relax stress caused by shrinkage of the polarizer and effectively compensate negative birefringence. Therefore, the polarizer and the LCD device using the pressure-sensitive adhesive composition can prevent light leakage originating from stress concentration in spite of long-term use.

Abstract: A light diffusion sheet usable, for example, in backlight units, includes a transparent substrate layer, and a light diffusion layer overlaid on a front face of the substrate layer. The light diffusion layer includes resin beads and a resin binder, the resin beads being provided as monodisperse beads having a mean particle size of 1.5 ?m or greater and 5 ?m or less. A weight ratio of the monodisperse beads to the binder is 2.5 or greater and 3 or less, and an amount of the overlaid light diffusion layer is 3 g/m2 or greater and 10 g/m2 or less. An acrylic resin may be used as the substrate polymer of the monodisperse beads and binder. A coefficient of variation of particle size distribution of the monodisperse beads is preferably equal to or less than 0.2. Advantageously, a gravure coating method is employed for forming the light diffusion layer.

Abstract: A liquid crystal display includes a first substrate, a second substrate, and a liquid crystal layer. The first substrate includes a first insulating substrate, in which a pixel area is defined, a gate line formed on the first insulating substrate, a data line crossing the gate line, and a thin film transistor connected to the gate line and the data line. The second substrate is opposite to the first substrate. The liquid crystal layer is interposed between the first and second substrates and includes a liquid crystal composition with a nematic-isotropic phase transition temperature (Tni) of 79° C. or above.

Abstract: An optical compensation structure and a display device are disclosed. The former comprises a front side polarizer and a rear side polarizer arranged at both sides of a VA liquid crystal unit; the front side polarizer includes a front side polarization unit and a first front side TAC film; the absorption axis of the front side polarization unit is perpendicular to the horizontal normal of the VA liquid crystal unit; the rear side polarizer includes a rear side polarization unit and a biaxial film; and the absorption axis of the rear side polarization unit is parallel to the horizontal normal. The region having serious dark-state light leakage can be transferred from a horizontal viewing angle to a vertical viewing angle, which improves the display effect. Meanwhile, there is no addition of the number of layers of the biaxial film which reduces the cost.

Abstract: An object is to provide a novel liquid crystal composition that can be used for a variety of liquid crystal devices. Particularly, a novel liquid crystal composition is used to achieve a reduction in driving voltage of a liquid crystal element and a reduction in power consumption of a liquid crystal display device. The liquid crystal composition includes a polymerizable monomer represented by the general formula (G1), a nematic liquid crystal, and a chiral agent. In the general formula (G1), n and m are individually an integer from 1 to 20, and R1 and R2 individually represent hydrogen or a methyl group.

Abstract: A lengthy stretched film made of a thermoplastic resin, having, over the width direction of at least 1300 mm, a value of an orientation angle ? to a take-up direction in a range of 40° to 50° and fluctuation thereof of 1.0° or less, and a value of an average Nz coefficient in a range of 1.3 to 2.0 and fluctuation thereof of 0.10 or less. A lengthy circularly polarizing plate constituted by laminating the lengthy stretched film with a lengthy polarizer. A reflective display type liquid crystal display device provided with the circularly polarizing plate constituted by trimming the lengthy circularly polarizing plate to a desired size.

Abstract: The present invention provides uniaxially stretched polymer films that have a refractive index profile suitable for use as negative A-plates or biaxial birefringent plates in a liquid crystal display (LCD) device. These wave plates can be used to compensate for the phase retardations existing in various modes of LCDs including TN (twisted nematic), VA (vertically aligned), IPS (in-plane switching), and OCB (optically compensated bend), and therefore improving the viewing quality of the displays.

Abstract: A liquid crystal composition containing a polymerizable compound according to the present invention is used in a liquid crystal display element in which a liquid crystal alignment capability is provided through polymerization. The liquid crystal composition contains a polymerizable compound that polymerizes without a photopolymerization initiator or with an extremely small amount of photopolymerization initiator. Therefore, the alignment properties after the polymerization become more stable and the display characteristics do not degrade. Thus, the polymerizable compound is suitable as a practical component of the liquid crystal composition. A liquid crystal display element that uses the liquid crystal composition containing a polymerizable compound according to the present invention can be suitably used for VA and IPS liquid crystal display elements.

Abstract: The invention is to provide a new liquid crystal compound having a high clearing point, a good compatibility with other compounds, a small viscosity, and a high stability to heat, light and so forth; compound (1) is provided: R1CF2nR2??(1) wherein, for example, R1 is alkyl having 4 to 10 carbons or —(CH2)2—CH?CH2, R2 is alkyl having 2 to 10 carbons, n is 8, and R1 and R2 are not allowed to be straight-chain alkyl having an identical number of carbons.

Abstract: An anti-dazzling laminate made of an optical laminate including a light transparent base material and an anti-dazzling layer having a concavoconvex shape provided on the material. The laminate simultaneously satisfies formulae: 0?G100?15 (I), 0.1?Hs?5.0 (II), 0.3?Rz?1.8 (III) wherein G100 represents a scintillation value which is a standard deviation of a variation in brightness distribution at a resolution of 100 ppi measured on the surface of the laminate; Hs represents the surface haze value of the laminate; and Rz represents the average roughness of the concavoconvex shape of the anti-dazzling layer.

Abstract: A cellulose acylate film containing a cellulose acylate and a specific polymer, the specific polymer containing a repeating unit derived from a monomer represented by formula (1): wherein R1 represents a hydrogen atom or an aliphatic group having 1 to 4 carbon atoms; R2 represents a substituent; (A) represents an atomic group necessary to form a 5- or 6-membered ring; and n represents an integer of 0 to 4.

Abstract: A cholesteric liquid-crystal composition is described, which contains a liquid-crystal component and a chiral agent, and has a selective reflection wavelength in the range of 400 nm to 800 nm at 25° C.

Abstract: A liquid crystal display device includes a first substrate, a second substrate facing the first substrate, and a liquid crystal layer between the first and second substrates. The liquid crystal layer includes a liquid crystal composition including an alkenyl liquid crystal and an antioxidant component including at least one selected from an antioxidant and a derivative thereof. In an embodiment, the antioxidant component is present in an amount of greater than 0 ppm and equal to or less than about 10,000 ppm relative to the total weight of the liquid crystal composition.

Abstract: A liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of the nematic phase, a small viscosity, a suitable optical anisotropy, a large dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or having a suitable balance regarding at least two of the characteristics is provided; and an AM device having a short response time, a suitable pretilt, a large voltage holding ratio, a large contrast ratio, a long service life and so forth is provided. A solution is a liquid crystal composition containing a specific compound having a high maximum temperature and a large dielectric anisotropy as a first component and a polymerizable compound as a second component, and a liquid crystal display device including the composition.

Abstract: To provide a liquid crystal composition satisfying at least one characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature thereof, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy and specific resistance, high stability to ultraviolet light and heat, or having a suitable balance regarding at least two of the characteristics; an AM device having short response time, a large voltage holding ratio and contrast ratio, and a long life. A liquid crystal composition has a nematic phase and contains a specific straight-chain compound as a first component and a specific compound having a large dielectric anisotropy as second component, and may contain a specific compound having a high maximum temperature or small viscosity as a third component and a specific compound having a high maximum temperature or large dielectric anisotropy as a fourth component, and a liquid crystal display device includes the composition.

Abstract: The compound represented by formula (1). For example, the rings A1, A2, A3 and A4 are 1,4-phenylene, Z1 and Z2 are alkylene having 1 to 10 carbons in which at least one —CH2— may be replaced by —O— or —CH?CH—; L1, L2 and L3 are a single bond, —COO— or —CH?CH—; G1 and G2 are —O—; s, t and u are 0 or 1; and P1 and P2 is the group (P-1), the group (P-2) or the group (P-3). M1 and M2 are hydrogen or methyl.

Abstract: A liquid crystal display panel includes a liquid crystal cell, a first polarizing plate placed on one side of the liquid crystal cell, a second polarizing plate placed on the other side of the liquid crystal cell, a retardation film placed between the liquid crystal cell and the first polarizing plate, and a pressure-sensitive adhesive layer placed between the liquid crystal cell and the retardation film, wherein the first and second polarizing plates have absorption axes whose directions are substantially orthogonal to each other, the retardation film is a norbornene resin-containing stretched film and has a refractive index ellipsoid satisfying the relation nx?nz>ny, and the pressure-sensitive adhesive layer includes a pressure-sensitive adhesive that may be produced by crosslinking a composition including a (meth)acrylate (co)polymer and a crosslinking agent including a peroxide as a main component.

Abstract: A system having a ferroelectric liquid host material and a small amount of polymer additive is provided. In an embodiment, the polymer additive improves the physical characteristics of the system. In an embodiment, the system can be used in FLC applications.

Abstract: The present invention relates to a liquid-crystalline medium, characterised in that it contains a polymerisable component (A) containing one more polymerisable compounds and a liquid-crystalline component (B) containing one more compounds of the general formula I in which R, rings A1 and A2, Z1, Z2, Y1, Y2, X0 and r are as defined in Claim 1.

Abstract: The present invention relates to a liquid-crystalline medium, characterized in that it contains a polymerizable component (A) containing one more polymerizable compounds and a liquid-crystalline component (B) containing one more compounds of the general formula I in which R, rings A1 and A2, Z1, Z2, Y1, Y2, X0 and r are as defined in Claim 1.

Abstract: The invention relates to an electro-optical liquid-crystal display which contains, as dielectric, a liquid-crystalline medium having negative dielectric anisotropy and includes a backlight which essentially only emits light having a wavelength of 400 nm or more or has, between the liquid-crystal layer and the backlight, a cut-off filter which essentially only allows light having a wavelength of 420 nm or more to pass through. In particular, the liquid-crystalline medium comprises a) a (first) dielectrically negative component (component A) which consists of one or more dielectrically negative compounds of the formula I in which the parameters have the meanings indicated in claim 2, and a further (second) dielectrically negative component (component B).

Abstract: The purpose of the present invention is to provide a retardation film which has high retardation developability, good mechanical strength and good durability. This retardation film contains a cellulose derivative and at least one compound represented by general formula (1), wherein each of R1 and R2 independently represents an alkyl group, a cycloalkyl group, an aryl group or a heterocyclic group; X1 represents a single bond, —NR4—, —O— or —S—; X2 represents a single bond, —NR5—, —NR5—(C?O)—, —O— or —S—; each of R4 and R5 independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a heterocyclic group; R3 represents a substituent; n represents an integer of 0-4; and when n is 2 or more, a plurality of R3s may be the same or different and adjacent R3s may be joined together to form a ring).

Abstract: A cellulose acylate film containing a cellulose acylate and a sugar ester compound having from 1 to 12 pyranose structures or furanose structures in which at least one hydroxyl group is esterified, the film satisfying 40 nm?Re(550)?60 nm and 100 nm?Rth(550)?140 nm, and having a dimensional change of ?0.5 to 0.5% and an internal haze of at most 0.1%.

Abstract: The liquid crystal composition has a negative dielectric anisotropy, and contains a specific bicyclic compound having a large optical anisotropy and negative dielectric anisotropy as a first component and a specific tricyclic compound having a large dielectric anisotropy as a second component, and may contain a specific compound having a small viscosity as a third component, a specific compound having a large dielectric anisotropy and a small viscosity as a fourth component and a specific compound having a large dielectric anisotropy as a fifth component, and the liquid crystal display device includes the composition.

Abstract: To provide a liquid crystal composition satisfying at least one characteristic including a high maximum temperature of a nematic phase, a low minimum temperature thereof, a small viscosity, a large optical anisotropy, dielectric anisotropy and specific resistance, a high stability to ultraviolet light and heat, or a liquid crystal composition having a suitable balance regarding at least two characteristics; and an AM device having a short response time, a large voltage holding ratio and contrast ratio and a long life; a liquid crystal composition has a negative dielectric anisotropy and contains a compound having a low minimum temperature as a first component and a compound having a large negative dielectric anisotropy as a second component, and may contain a compound having a small viscosity as a third component and a compound having a large negative dielectric anisotropy as a fourth component, and a liquid crystal display device containing the composition.

Abstract: Disclosed is a material roll that includes a roll of an optical film having defect information markings printed thereon and is resistant to the formation of a defect by the transfer of a bump/dent deformation at the marking site. The material roll includes a long sheet of an optical film with polarizer wound into roll shape; and marking(s) formed at or in a vicinity of at least one defect site. The marking has an optical density of 1.5 or more, and a thickness of a center part of the marking is 1.5 ?m or less. The marking preferably has an optical density per unit thickness of 2.5 ?m?1 or more.

Abstract: The retardation film of the present invention contains a thermoplastic polymer having at least a side chain component (A) oriented in a direction substantially orthogonal to a slow axis, and the absorption edge wavelength (?cut-off) of the side chain component (A) is 330 nm or more, and an in-plane retardation value (Re[450]) at a wavelength of 450 nm is smaller than that (Re[650]) at a wavelength of 650 nm. In the above-mentioned retardation film, the difference (?Re650-450=Re[650]?Re[450]) between the in-plane retardation value (Re[650]) at a wavelength of 650 nm and the in-plane retardation value (Re[450]) at a wavelength of 450 nm is preferably 10 nm or more. The retardation film of the present invention exhibits optical characteristics in which the in-plane birefringence is large and the difference between a retardation value on the short wavelength side and a retardation value on the long wavelength side is large.

Abstract: Provided is a polymer film containing at least one of a compound represented by formula (1) of hydrates, solvates, or salts thereof. Y is a methine group or nitrogen atom. Qa, Qb, and Qc are a single bond or a divalent linking group. Ra, Rb, and Rc, are hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, cyano group, halogen group, or heterocyclic group. X2 is a single bond or a divalent linking group. X1 is a single bond or a predetermined divalent linking group.

Abstract: The present invention relates to liquid-crystalline media (LC media) comprising thiophene derivatives and to liquid-crystal displays (LC displays) containing these LC media. The media have high optical anisotropy and preferably have a content of thiophene derivatives of 25% by weight or more.

Abstract: Provide is a cellulose acylate film, of which the environmental humidity-dependent retardation change is small and which, when stuck to a polarizer and used in high-temperature and high-humidity environments, is effective for preventing the polarizing element from being deteriorated. A cellulose acylate film, which contains a hydrogen-bonding compound satisfying the following requirements (A) to (C), and at least one hydrophobizing agent selected from a polyalcohol ester-base hydrophobizing agent, a polycondensate ester-base hydrophobizing agent and a carbohydrate derivative-base hydrophobizing agent: (A) the compound has both a hydrogen-bonding donor part and a hydrogen-bonding acceptor part in one molecule, (B) the value computed by dividing the molecular weight of the compound by the total number of the hydrogen-bonding donor number and the hydrogen-bonding acceptor number in the compound is from 30 to 65, and (C) the total number of the aromatic ring structures in the compound is from 1 to 3.

Abstract: The present invention relates generally to the field of organic chemistry and particularly to the nematic lyotropic liquid crystal solution and negative dispersion retardation plate for application in 3D liquid crystal displays. The negative dispersion retardation plate comprises a substrate, and at least one optically anisotropic retardation layer comprising a multi-component guest-host composition coated onto the substrate.

Abstract: Provided are a cellulose acylate film used for optical compensation and additives used therefor and, more particularly, is a cellulose acylate film with mechanical physical properties, in particular, very improved modulus affecting film durability.

Abstract: Provided is a polymer film containing at least one of a compound represented by formula (1) of hydrates, solvates, or salts thereof. Y is a methine group or nitrogen atom. Qa, Qb, and Qc are a single bond or a divalent linking group. Ra, Rb, and Rc, are hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, cyano group, halogen group, or heterocyclic group. X2 is a single bond or a divalent linking group. X1 is a single bond or a predetermined divalent linking group. R1 and R2 are a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, or heterocyclic group.