A photochromic hydroxyurethane compound of the present invention is characterized in that, on condition of having at least one photochromic moiety as the photochromic minimal unit in a molecule, it has a hydroxyurethane constitutional unit represented by Formula (1):

—X—O—CO—NH—  (1)

In the formula, X is an oxygen-containing chain organic group having a hydroxyl group as a substituent, or a hydrogen atom in the hydroxyl group is substituted by any one of (A): a photochromic group having the photochromic moiety; (B): a polymerization reactive group having a polymerizable substituent; (C) an alkyl group having 1 to 10 carbon atoms; (D) a cycloalkyl group having 3 to 10 carbon atoms; or (E): an aryl group having 6 to 14 carbon atoms (each of the groups (C)-(E) can be bonded to an oxygen atom derived from the hydroxyl group via the oxygen-containing chain organic group).

An electrochromic polymer is comprised of a repeat unit comprising one or more meta-conjugated linkers (MCLs) and one or more aromatic moieties (Ars). Each of the one or more MCLs is partially conjugated with the one or more Ars at meta positions of the MCLs to form a polymer backbone of the electrochromic polymer. The electrochromic polymer undergoes an optical switching and a color change in an electrochromic device, which shows a high transparency and a high optical contrast.

A polymer containing an optionally substituted repeat unit of formula (I) wherein each R is the same or different and represents H or an electron withdrawing group, and each R.sup.1 is the same or different and represents a substituent. ##STR00001##

A particle comprising an inorganic matrix material; a first light-emitting material; and a second light-emitting material, wherein the first light-emitting material is a light-emitting polymer. The first and second light-emitting materials may have opposing ionic charges. The first light-emitting material may transfer excitation energy to the second light-emitting material. A biomolecule binding group may be bound to the particle.

A light emitting device with excellent light emission efficiency is provided. The light emitting device has an anode, a cathode, a first layer disposed between the anode and the cathode, and a second layer disposed between the anode and the first layer. The second layer is a layer containing a crosslinked product of a compound having a crosslinkable group selected from Group A, and at least one of the first layer and the second layers contains a compound represented by the formula (T-1). The compound having a crosslinkable group is a polymer compound having a crosslinkable group selected from Group A:

##STR00001## ##STR00002##

A particle having an inorganic matrix material and a light-emitting polymer wherein the light-emitting polymer has a light-emitting group and a host repeat unit, wherein a bandgap of the host repeat unit is greater than that of the light-emitting group, wherein the light-emitting group makes up no more than 10 mol % of the groups of the light-emitting polymer and wherein the polymer has a solubility in water or a Ci-s alcohol at 20° C. of at least 0.1 mg/mL.

The present invention relates to indane derivatives of the formula (I) and mixtures thereof, wherein X is selected from groups of the formulae -A-NH2 or -A-(NAr.sub.2), wherein A is a chemical bond or phenylene which is unsubstituted or substituted by 1, 2, 3 or 4 substituents selected from C.sub.1-C.sub.6 alkyl and C.sub.1-C.sub.6-alkoxy; Ar is unsubstituted or substituted aryl, wherein two groups Ar bound to the same nitrogen atom may together with the nitrogen atom also form a fused ring system having 3 or more than 3 unsubstituted or substituted rings; and the variables R.sup.A, R.sup.B, Y, k, I, m, p, q and r are as defined in the claims and the description. The invention further relates to methods for preparing such compounds and their use in organic electronics, in particular as hole transport material or electron blocking material.

##STR00001##

Light harvesting luminescent multichromophores that are configured upon excitation to transfer energy to, and amplify the emission from, an acceptor signaling chromophore in energy-receiving proximity therewith are provided. Also provided are compositions for labelling a target. The labelling composition may include a donor light harvesting multichromophore and an acceptor signaling chromophore in energy-receiving proximity to the donor light harvesting multichromophore. Also provided is an aqueous composition for labelling a target, including: a donor light harvesting multichromophore; an acceptor signaling chromophore in energy-receiving proximity therewith; and a sensor biomolecule. Methods for using the subject compositions are also provided.

Provided are an organometallic compound represented by Formula 1, an organic light-emitting device including the organometallic compound, and a diagnostic composition including the organometallic compound:
M(L.sub.1).sub.n1(L.sub.2).sub.n2  Formula 1 wherein, in Formula 1, M, L.sub.1, L.sub.2, n1 and n2 may each be understood by referring to the descriptions thereof provided herein.

The present disclosure provides a light emitting device having an anode and a cathode, and a first layer and a second layer disposed between the anode and the cathode.