The present specification relates to a polymer including a first unit of Chemical Formula 1; a second unit of Chemical Formula 2; and a third unit of Chemical Formula 3 or 4, and an organic solar cell including the same.

A compound having the formula (L.sub.A).sub.mIr(L.sub.B).sub.3-m, where L.sub.A is

##STR00001##

and L.sub.B is

##STR00002##

is disclosed. In the formula (L.sub.A).sub.mIr(L.sub.B).sub.3-m, L.sub.A and L.sub.B are different; each of X.sup.1 to X.sup.5 is C—R.sub.F or nitrogen; X is selected from O, S, and Se; each R.sup.1, R.sup.2, R.sub.B, R.sub.D, and R.sub.F is hydrogen or a substituent; R.sup.3 is alkyl, cycloalkyl, or a combination thereof; and m is 1 or 2. OLEDs, consumer products, and formulations including the compound are also disclosed.

Compounds that are organic radicals that can have a dual function. The compounds can be fluorescent emitters that emit in the near-IR. The compounds can also facilitate reverse intersystem crossing (RISC) to convert triplet excitons in an OLED to singlet excited states to maximize utilization of generated excitons in the OLED and approach 100% internal quantum efficiency.

The present invention relates to an organic electroluminescent device containing a mixture which comprises an electron-transporting host material and a hole-transporting host material, to a formulation comprising a mixture of the host materials and to a mixture comprising the host materials. The electron-transporting host material corresponds to a compound of the formula (1) from the class of compounds containing two triazine units. The hole-transporting host material corresponds to a compound of the formula (2) from the class of the biscarbazoles or derivatives thereof.

The compound represented by formula (1):

##STR00001##

wherein symbols are as defined in the description, provides an organic electroluminescence device having a device performance further improved.

Provided is an organic light emitting device including a light emitting layer comprising a compound of Chemical Formula 1 and a first organic material layer comprising a compound of Chemical Formula 2:

##STR00001## wherein: Cy1 to Cy5 are each independently one selected from among a substituted or unsubstituted: aromatic hydrocarbon ring, aliphatic hydrocarbon ring, and aromatic hetero ring, or a ring in which two or more rings selected from the above group are fused, one or more of Cy1 to Cy5 are a ring of Chemical Formula 1-A:

##STR00002## one to three of a* to d* are a position fused to or linked to Chemical Formula 1;

##STR00003## L1 to L3 are each independently a direct bond or a substituted or unsubstituted: arylene or divalent heterocyclic group; and Ar1 and Ar2 are each independently a substituted or unsubstituted: aryl or heterocyclic group.

Provided is an organic light emitting device including an anode; a cathode; a light emitting layer between the anode and the cathode; a first organic material layer between the light emitting layer and the anode; and a second organic material layer between the light emitting layer and the cathode, wherein the first organic material layer comprises a compound of Chemical Formula 1, the light emitting layer comprises a compound of Chemical Formula 2, the second organic material layer comprises a compound of Chemical Formula 3, and Chemical Formula 1 and Chemical Formula 3 satisfy one or more of <Equation 1> to <Equation 3>:

##STR00001##

|E.sub.L1|<E.sub.L3|  <Equation 1>

E.sub.s1>E.sub.s3  <Equation 2>

E.sub.T1>E.sub.T3  <Equation 3>

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 electroluminescence device includes: an anode; an emitting layer; and a cathode, the emitting layer containing a first material, a second material and a third material, the first material being a fluorescent material, the second material being a delayed fluorescent material, the third material having a singlet energy larger than a singlet energy of the second material.

A novel light-emitting element is provided. A light-emitting element with a long lifetime is provided. A light-emitting element with high emission efficiency is provided. In the light-emitting element, an EL layer includes a hole-injection layer, a first hole-transport layer, a second hole-transport layer, a third hole-transport layer, a light-emitting layer, a first electron-transport layer, and a second electron-transport layer in this order; the hole-injection layer includes an organic acceptor; the LUMO level of the host material is higher than that of the first electron-transport layer; the LUMO level of the second electron-transport layer is higher than that of the first electron-transport layer; the host material is a substance including a condensed aromatic ring skeleton; and the first and second electron-transport layers each include a substance having a heteroaromatic ring skeleton.