A novel compound having a first ligand L.sub.A of ##STR00001##
is disclosed. The compound is useful as emitter dopant in OLEDs.

A method of producing a photochromic resin body includes a first step, a second step and a third step. In the first step, a sublimable photochromic dye having sublimability is applied to a base body so as to obtain a function-adding base body. In the second step, the function-adding base body obtained in the first step is set to face a resin body, the function-adding base body is heated to sublimate the sublimable photochromic dye applied to the function-adding base body, and the sublimable photochromic dye is deposited on the resin body. In the third step, the resin body on which the sublimable photochromic dye is deposited in the second step is heated to fix the sublimable photochromic dye on the resin body.

Iridium complexes comprising three different bidentate ligands and their use in OLEDs to enhance the device efficiency and lifetime are disclosed. The complexes have a structure of the formula Ir(L.sub.A)(L.sub.B)(L.sub.C), where ligand L.sub.A is selected from a variety of structures, ligand L.sub.B has the structure

##STR00001##

and L.sub.C has the structure

##STR00002##

In these structures rings A, B, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring; R.sup.1, R.sup.2, R.sup.3, R.sup.A, R.sup.B, R.sup.C, and R.sup.D can be any of a variety of substituents, and Z.sup.1 and Z.sup.2 are each independently C or N.

The photochromic compound is represented by the following general formula (1):

##STR00001##

wherein, X denotes an oxygen atom or a nitrogen atom unsubstituted or substituted by a substituent selected from the following Y.sup.1 group:
Y.sup.1 group: —R.sup.1, -A.sup.1(B.sup.1).sub.l(A.sup.2).sub.m(B.sup.2).sub.nR.sup.2, -A.sup.3A.sup.4, -A.sup.5R.sup.3
R.sup.1 denotes a cyano group or the like,
R.sup.2 denotes an alkyl group or the like,
R.sup.a denotes a halogen atom or the like,
A.sup.1, A.sup.2, A.sup.3, and A.sup.5 each independently denote an alkylene group or the like,
A.sup.4 denotes a naphthyl group which may be substituted,
B.sup.1 and B.sup.2 each independently denote any one of the divalent groups selected from the following group:

##STR00002##

l, m, and n are each independently 0 or 1, provided that n is 0 if m is 0,
Y.sup.2 denotes a hydrogen atom or the like,
R denotes a hydrogen atom or the like,

##STR00003##

denotes a norbornylidene group or the like.

Provided is a blue light emitting organic EL device having high emission efficiency and a long lifetime. This organic EL device includes one or more light emitting layers between an anode and a cathode opposite to each other, wherein at least one of the light emitting layers includes a first host selected from indolocarbazole compounds, a second host selected from the compounds represented by the following general formula (2), and, as a light emitting dopant, a polycyclic aromatic compound represented by the following general formula (3) or a polycyclic aromatic compound represented by the general formula (3) as a substructure, wherein Y.sup.4 is B, P, P═O, P═S, Al, Ga, As, Si—R.sup.4 or Ge—R.sup.5, and X.sup.4 is O, N—Ar.sup.4, S or Se.

##STR00001##

An organic light emitting diode and an organic light emitting device including the organic light emitting diode are discussed. The organic light emitting diode can include a first compound represented by the following formula, a second compound as a p-type host and a third compound as an n-type host in an emitting material layer. As a result, the organic light emitting diode and the organic light emitting device have advantages in the driving voltage, the luminous efficiency and the lifespan.

##STR00001##

Provided are organometallic compounds. Also provided are formulations comprising these organometallic compounds. Further provided are OLEDs and related consumer products that utilize these organometallic compounds.

An organic light-emitting device includes a first electrode, a second electrode facing the first electrode, an organic layer between the first electrode and the second electrode and including an emission layer, and at least one of a first layer and a second layer, wherein the first layer is positioned in a path where light generated in the emission layer is transmitted to the outside through the first electrode and the second layer is positioned in a path where the light generated in the emission layer is transmitted to the outside through the second electrode. The first layer and the second layer each include a compound having a certain formula and absorbing external ultraviolet rays to prevent or reduce the ultraviolet (UV) rays from transmitting therethrough.

Platinum, palladium, and gold complexes suitable for use as phosphorescent emitters or as delayed fluorescent and phosphorescent emitters having the structure of Formula VIII. ##STR00001##

A composition containing a phosphorescent compound represented by the formula (1) and a compound (F) having a condensed hetero ring skeleton containing at least one atom (a) selected from the group consisting of a nitrogen atom and a boron atom in the ring is provided. If the value of the energy level in the lowest triplet excited state of the above-described phosphorescent compound is expressed as T.sub.p (eV), the value of the energy level of the lowest triplet excited state of the above-described compound (F) is expressed as T.sub.F (eV) and the number of the above-described atom (a) in the condensed hetero ring skeleton per 1000 of the molecular weight of the above-described compound (F) is expressed as N.sub.f, then, the formula (A) and the formula (B) are satisfied:

|T.sub.P|−|T.sub.F|≥0.15  (A)

0.01≤N.sub.f≤4.5  (B)

##STR00001##