An organic compound having the structure of Formula (I), shown below, is disclosed. When used in a hole injection layer or a hole transporting layer, it can greatly improve the balance of electron holes and electron transporting of a device, thereby bringing excellent device effects, for example, improving the efficiency and lifetime of a device. At the same time, it also achieves a good effect when the organic compound having the structure of Formula (I) is used as a P-type conductive doping material in a charge generation layer of a multi-layer OLED device. ##STR00001##

A compound of formula (I): (Formula (I)) wherein Ar.sup.1, Ar.sup.2 and Ar.sup.3 independently in each occurrence is a C.sub.6-20 aryl group or a 5-20 membered heteroaryl group which is unsubstituted or substituted with one or more substituents; X.sup.1, X.sup.2 and X.sup.3 in each occurrence is independently a direct bond or a group of formula —C(R.sup.1).sub.2— wherein R.sup.1 in each occurrence is independently H or a substituent. The compound of formula (I) may be used to form an n-dopant for doping an organic semiconductor. A film formed by such n-doping may be used in an organic electronic device, for example an electron injection layer of an organic light-emitting device. ##STR00001##

A light-emitting element includes an anode electrode and a cathode electrode, and is provided with a first hole transport layer, a second hole transport layer, a light-emitting layer, a first electron transport layer, and a second electron transport layer. At a HOMO level, an energy level difference between the second hole transport layer and the light-emitting layer on the second hole transport layer side is from 0.0 eV to 0.15 eV, and at a LUMO level, an energy level difference between the first electron transport layer and the light-emitting layer on the first electron transport layer side is from 0.0 eV to 0.15 eV. The second electron transport layer is a mixed layer that includes an organic material having electron transport properties and an electron-accepting material and contains the electron-accepting material in an amount greater than 50 mass %.

The present invention relates to soluble organic compounds, to compositions comprising these compounds, to formulations comprising the compounds or compositions, and to electronic devices.

Charged organic thermally activated delayed fluorescence (TADF) species are described. A light-emitting electrochemical cell (LEEC) includes the charged organic thermally activated delayed fluorescence (TADF) species and sufficient counter ions to balance the charge on the charged organic thermally activated delayed fluorescence species, as emitter material. Also disclosed are OLEDSs containing the TADF species.

A compound of formula (7) is provided ##STR00001## wherein L.sub.4 is a linking group selected from the group consisting of: ##STR00002## provided that an asterisk (*) indicates the position bonding to the nitrogen atom of the carbazolyl group, R.sub.6 to R.sub.13 are independently a hydrogen atom, or a phenyl group, Ar.sub.17 is an unsubstituted phenylphenyl group, and Ar.sub.18 is a phenylphenyl group which may be substituted by a phenyl group or a naphthyl group, or a phenyl group which may be substituted by a naphthyl group.

An object of one embodiment of the present invention is to provide a multicolor light-emitting element that utilizes fluorescence and phosphorescence and is advantageous for practical application. The light-emitting element has a stacked-layer structure of a first light-emitting layer containing a host material and a fluorescent substance, a separation layer containing a substance having a hole-transport property and a substance having an electron-transport property, and a second light-emitting layer containing two kinds of organic compounds that form an exciplex and a substance that can convert triplet excitation energy into luminescence. Note that a light-emitting element in which light emitted from the first light-emitting layer has an emission spectrum peak on the shorter wavelength side than an emission spectrum peak of the second light-emitting layer is more effective.

An object is to provide a light-emitting element which uses a plurality of kinds of light-emitting dopants and has high emission efficiency. In one embodiment of the present invention, a light-emitting device, a light-emitting module, a light-emitting display device, an electronic device, and a lighting device each having reduced power consumption by using the above light-emitting element are provided. Attention is paid to Förster mechanism, which is one of mechanisms of intermolecular energy transfer. Efficient energy transfer by Förster mechanism is achieved by making an emission wavelength of a molecule which donates energy overlap with the longest-wavelength-side local maximum peak of a graph obtained by multiplying an absorption spectrum of a molecule which receives energy by a wavelength raised to the fourth power.

A highly reliable micromachine, display element, or the like is provided. As a micromachine or a transistor including the micromachine, a transistor including an oxide semiconductor in a semiconductor layer where a channel is formed is used. For example, a transistor including an oxide semiconductor is used as at least one transistor in one or a plurality of transistors driving a micromachine.

The present invention concerns a device for room temperature reverse-bias operation photo-detection. The device comprising:—a planar first electrode extending in a planar direction;—a second electrode positioned above the first electrode in a direction substantially perpendicular to said planar direction; and—an active region sandwiched between the first and second electrode. The active region consists of a light absorbing perovskite and wherein the light absorbing perovskite is in direct contact with at least one of the first and second electrodes.