Abstract: 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.

Abstract: A compound is represented by a formula (20) below.

Abstract: An organic electroluminescence device includes an anode, an emitting layer, and a cathode in this order. The emitting layer comprises a delayed fluorescent compound M2 and a compound M3 having at least one deuterium atom, and the compound M3 is not a compound having a partial structure represented by a formula (1C) or (2C). S1(M2) of the compound M2 and S1(M3) of the compound M3 satisfy a relationship of S1(M3)>S1(M2). In the formulae (1C) and (2C), Y41 to Y48 are each independently a N atom, CR, or a C atom bonded to another atom or the like in the compound M3, where each R is independently a H atom or a substituent, at least one of Y41 to Y48 is a N atom, and at least one of Y41 to Y48 is a C atom bonded to another atom or the like in the compound M3.

Abstract: An organic electroluminescence device includes: an anode; a cathode; and an emitting layer provided between the anode and the cathode, in which the emitting layer contains a delayed fluorescent compound M2 and a compound M3 represented by a formula (3) and a singlet energy S1(M2) of the compound M2 and a singlet energy S1(M3) of the compound M3 satisfy a relationship of a numerical formula (Numerical Formula 1) below, S1(M3)>S1(M2) . . . (Numerical Formula 1). In the formula (3), A3 is a group represented by a formula (3a) or the like.

Abstract: An organic EL device includes: an anode, a cathode, and an emitting layer, in which the emitting layer contains a first compound of a formula (1), a second compound of a formula (2), and a third compound that exhibits delayed fluorescence, and singlet energies S1 of the first compound, the second compound, and the third compound satisfy Numerical Formula 1 and Numerical Formula 2. In the formula (1), A represents a group of a formula (a1) or the like, L represents a linking group or the like, and B represents an aryl group or the like. The first compound of the formula (1) has no carbonyl group. In the formula (2), Y21 to Y26 each independently represent an N atom, CRA, or the like. RA represents a substituent, a group of a formula (2A), or the like.

Abstract: 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.

Abstract: There is provided an organic EL device, including: an anode; a cathode; an emitting layer provided between the anode and the cathode; a first layer provided between the anode and the emitting layer; and a second layer provided between the anode and the first layer, in which the emitting layer contains a delayed fluorescent compound, the first layer contains a first compound, the second layer contains a second compound, an ionization potential Ip(HT1) of the first compound satisfies Numerical Formula 1, a hole mobility ?h(HT1) of the first compound satisfies Numerical Formula 2, an ionization potential Ip(HT2) of the second compound satisfies Numerical Formula 3, and the first layer has a film thickness of 15 nm or more, Ip(HT1)?5.69 eV??(Numerical Formula 1) ?h(HT1)?1.00×10?5 cm2/Vs??(Numerical Formula 2) Ip(HT2)?5.60 eV??(Numerical Formula 3).

Abstract: An organic electroluminescence device includes an anode, an emitting layer, and a cathode. The emitting layer contains a delayed fluorescent first compound, a fluorescent second compound, and a third compound represented by Cz-Az. The second compound emits light with a main peak wavelength ranging from 430 nm to 540 nm. Az is a cyclic structure selected from the group consisting of a substituted or unsubstituted pyridine ring, a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted triazine ring, and a substituted or unsubstituted pyrazine ring. Cz is represented by a formula (3B) below.

Abstract: A compound of formula (11) to (13) wherein R1 to R4 are each independently D1 of a formula (1-1) etc. or D2 of a formula (2-1) etc. at least one of R1 to R4 being D1, and at least one of R1 to R4 being D2. In (1-1) and (2-1), X1 is O or S, R101 to R110 and R161 to R168 are each independently H, a substituent etc. In at least one D1, at least one of R101 to R110 is a group of a formula (110) or (120): Z1 is a C etc., a ring (B) is an aromatic hydrocarbon ring etc., Y12 to Y14 are each independently CR10A etc., Y21 to Y24 are each independently CR20A etc., Z2 is an aryl group etc., and * is a bonding position.

Abstract: An organic electroluminescence device includes an anode, a cathode, and an emitting layer disposed between the anode and the cathode. The emitting layer comprises a delayed fluorescent compound M2 having at least one deuterium atom and a compound M3 having at least one deuterium atom. A singlet energy S1(M2) of the compound M2 and a singlet energy S1(M3) of the compound M3 satisfy the relationship S1(M3)>S1(M2).

Abstract: A compound is represented by a formula (1) below, in which k is an integer of 0 or more, m is an integer of 1 or more, n is an integer of 2 or more. L is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, CN is a cyano group, and D1 and D2 are each independently represented by one of a formula (2), a formula (3) and formula (3x) below, D1 and D2 being optionally mutually the same or different.

Abstract: A compound is represented by one of formulae (11) to (13). R1 to R4 each independently represent a group represented by a formula (1-1) or the like, or a group represented by a formula (2-1), a group represented by a formula (2-2) or the like. At least one of R1 to R4 is the group represented by the formula (1-1) or the like. At least one of R1 to R4 is the group represented by the formula (2-1), (2-2) or the like. For instance, X1 represents an oxygen atom, a sulfur atom, or CR151R152, R101 to R110 and R151 and R152 each independently representing a hydrogen atom or a substituent. For instance, R161 to R168 and R171 and R180 each independently represent a hydrogen atom or a substituent.

Abstract: An organic electroluminescence device includes an anode, an emitting layer, and a cathode. The emitting layer contains a delayed fluorescent first compound, a fluorescent second compound, and a third compound represented by Cz-Az. The second compound emits light with a main peak wavelength ranging from 430 nm to 540 nm. Az is a cyclic structure selected from the group consisting of a substituted or unsubstituted pyridine ring, a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted triazine ring, and a substituted or unsubstituted pyrazine ring. Cz is represented by a formula (3B) below.

Abstract: An organic electroluminescence device includes an anode, an emitting layer, and a cathode, in which the emitting layer contains a first compound represented by a formula (1) and a fluorescent second compound. A singlet energy S1(M1) of the first compound is larger than a singlet energy S1(FL) of the fluorescent second compound. A is a group represented by a formula (1b).

Abstract: An organic-EL device includes an emitting-layer, first-layer adjacent to the emitting-layer near the anode, and second-layer adjacent to the emitting-layer near the cathode. The emitting-layer contains first, second and third compounds. The first-layer contains a compound of formula-(A). The second-layer contains a compound of formula-(B). The first, second and third compounds are a fluorescent compound of formula-(1), delayed-fluorescent compound of formula-(2), and compound of formula-(3), respectively. Singlet energies S1 of the first to third compounds satisfy S1(M3)>S1(M2)>S1(M1). In the formula-(A), Ra1-Ra5 etc. each represent a substituent etc. In the formula-(B), X1-X3 each represent N atom etc, Ar1 and Ar2 each represent a group of formula-(1B) etc. A represents the group of the formula-(1B). In the formula-(1B), HAr is of formula-(2B), a is 1 to 5, and L1 is a linking group etc. In the formula-(2B), X11-X18 each represent N atom etc, and Y1 represent O, S, or N atom etc.

Abstract: An organic EL device includes an emitting layer, a first layer adjacent to an anode-side of the emitting layer, and a second layer adjacent to a cathode-side thereof. The emitting layer contains first to third compounds. The first and second layers contain compounds of Formulae (1) and (2), respectively. The first and second compounds exhibits fluorescence and delayed fluorescence, respectively. Singlet energies S1 of the first to third compounds satisfy S1(M3)>S1(M2)>S1(M1). In Formula (1), Ra1-Ra5, Rb1-Rb5 and Rc1-Rc5 are each a substituent, etc. In Formula (2), X1-X3 are each nitrogen atom, etc, Ar1-Ar2 are each a group of Formula (2A) or aryl group, etc, A is a group of Formula (2A) in which HAr is of Formula (2B), a is 1 to 5, L1 is a linking group, etc.

Abstract: An organic electroluminescence device includes an anode, a cathode, and an emitting layer provided between the anode and the cathode, in which the emitting layer contains a delayed fluorescent compound M2 represented by a formula (2) and a compound M3 represented by a formula (3), and a singlet energy Si(M2) of the compound M2 and a singlet energy Si(M3) of the compound M3 satisfy a relationship of a numerical formula (Numerical Formula 1).

Abstract: A compound is represented by a formula (2) below.

Abstract: An organic EL device includes an anode, a cathode, and an emitting layer. The emitting layer contains a first compound represented by a formula (1X) or a formula (1Y), a second compound, and a third compound that exhibits delayed fluorescence. The second compound is different in structure from the first compound. The second compound is different in structure from the third compound. Singlet energies S1 of the first, second, third compounds satisfy Numerical Formula 1 and Numerical Formula 2 below, A is, for example, a group represented by a formula (a1); Y11˜Y13 are, for example, each independently a nitrogen atom or CRy; Ry is, for example, a substituent or a group represented by a formula (1Z); R1X to R3X are, for example, each independently a substituent or a group represented by a formula (1Z).

Abstract: An organic electroluminescence device includes: a cathode; an anode; and an organic thin-film layer disposed between the cathode and the anode, the organic thin-film layer having one or more layers including an emitting layer, in which the emitting layer includes a first material represented by the following formula (1) and a second material in a form of a fluorescent dopant material.