Fluorescence and delayed fluorescence-type organic light-emitting material and element

A fluorescence and delayed fluorescence organic light-emitting element, comprising:

• a substrate;
• an anode;
• a hole-transporting layer;
• at least one light-emitting layer comprising an organic light-emitting material having no metal atom in the molecule, which light-emitting material emits fluorescence and delayed fluorescence, the organic light-emitting material having a difference between excited singlet energy (S1) and excited triplet energy (T1) of 0.2 eV or less, the light-emitting layer being provided on the substrate, wherein light emission form the light-emitting layer consists substantially of fluorescence and delayed fluorescence which is generated substantially only by the organic light-emitting material;
• and
• a cathode.

A fluorescence and delayed fluorescence-type organic light-emitting element, comprising:

• a substrate;
• and
• at least one light-emitting layer comprising an organic light-emitting material represented by the general formula (1):
• in which:
• a ring A represents an aromatic ring represented by the formula (1a) to be fused with an adjacent ring at an arbitrary position;
• a ring B represents a heterocycle represented by the formula (1b) to be fused with an adjacent ring at an arbitrary position;
• Ar's in the formulae (1) and (1b) each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group;
• R's in the formulae (1) and (1a) each independently represent hydrogen or a monovalent substituent selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, and a substituted or unsubstituted aromatic six-membered heterocyclic group having 3 to 30 carbon atoms, provided that adjacent substituents may together form a ring;
• and n represents an integer of 1 or more and 4 or less, the light-emitting layer being provided on the substrate, wherein the light emission of the element includes 36% or more of a delayed fluorescence component.

A fluorescence and delayed fluorescence type organic light-emitting element, comprising:

• a substrate;
• and
• at least one light-emitting layer comprising an organic light-emitting material which emits fluorescence and delayed fluorescence and which has a difference between excited singlet energy (S1) and excited triplet energy (T1) of 0.2 eV or less, the light-emitting layer being provided on the substrate,
• wherein the organic light-emitting material comprises a compound represented by the following general formula (1):
• in which:
• a ring A represents an aromatic ring represented by the formula (1a) to be fused with an adjacent ring at an arbitrary position;
• a ring B represents a heterocycle represented by the formula (1b) to be fused with an adjacent ring at an arbitrary position;
• Ar's in the formulae (1) and (1b) each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group;
• R's in the formulae (1) and (1a) each independently represent hydrogen or a monovalent substituent selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, and a substituted or unsubstituted aromatic six-membered heterocyclic group having 3 to 30 carbon atoms, provided that adjacent substituents may together form a ring;
• and n represents an integer of 1 or more and 4 or less.

A fluorescence and delayed fluorescence type organic light-emitting element, comprising:

• a substrate;
• and
• at least one light-emitting layer comprising (i) an organic light-emitting material which emits fluorescence and delayed fluorescence and which has a difference between excited singlet energy (S1) and excited triplet energy (T1) of 0.2 eV or less, the light-emitting layer being provided on the substrate, and (ii) a host material having at least any one of excited singlet energy (S1) and excited triplet energy (T1) higher than those of the organic light-emitting material,
• wherein the organic light-emitting material comprises a compound represented by the following general formula (1):
• in which:
• a ring A represents an aromatic ring represented by the formula (1a) to be fused with an adjacent ring at an arbitrary position;
• a ring B represents a heterocycle represented by the formula (1b) to be fused with an adjacent ring at an arbitrary position;
• Ar's in the formulae (1) and (1b) each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group;
• R's in the formulae (1) and (1a) each independently represent hydrogen or a monovalent substituent selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, and a substituted or unsubstituted aromatic six-membered heterocyclic group having 3 to 30 carbon atoms, provided that adjacent substituents may together form a ring;
• and n represents an integer of 1 or more and 4 or less.