# US 12,193,324 B2 · Melt mixture for organic electroluminescent element, and organic electroluminescent element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,193,324 B2 - Document ID: US12193324B2 - Status: Granted - Kind: B2 - Application number: 17/442,601 - Filed: 2020-03-13 - Published: 2022-06-02 - Granted: 2025-01-07 - Earliest claimed: 2019-03-25 - Assignees: Nippon Steel Chemical & Material Co., Ltd. - Applicants: NIPPON STEEL Chemical & Material Co., Ltd. - Inventors: Masashi Tada; Yuta Sagara - Web page: https://patentgrep.com/patent/US12193324B2 ## CPC - C09K 11/06: containing organic luminescent materials - H10K 85/654: {comprising only nitrogen as heteroatom (H10K85/652 takes precedence)} - H10K 71/12: using liquid deposition, e.g. spin coating - H10K 71/164: {using vacuum deposition} - H10K 85/626: {containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene} - H10K 85/6572: {comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole} - H10K 85/6574: {comprising only oxygen in the heteroaromatic polycondensed ring system, e.g. cumarine dyes} - H10K 85/6576: {comprising only sulfur in the heteroaromatic polycondensed ring system, e.g. benzothiophene} - H10K 50/11: characterised by the electroluminescent [EL] layers - H10K 50/12: comprising dopants - H10K 2101/10: Triplet emission - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract Provided are an organic EL device having high luminous efficiency and a prolonged lifespan with a low driving voltage, and a melt mixture for an organic electroluminescent device used in the organic EL device. The melt mixture for an organic electroluminescent device is a melt mixture of at least two types of organic compounds including a first organic compound and a second organic compound, and a difference in vapor deposition temperature between the first organic compound and the second organic compound is 20° C. or less, and a difference between a PL maximum emission wavelength of the melt mixture and a PL maximum emission wavelength of any of the first organic compound and the second organic compound is within ±10 nm. The melt mixture is suitable as a host material of a light-emitting layer. ## Claims ### Claim 1 A melt mixture for an organic electroluminescent device which is a melt mixture of at least two types of organic compounds, wherein the two types of organic compounds include a first organic compound and a second organic compound, a difference in vapor deposition temperature between the first organic compound and the second organic compound is 20° C. or less, and a difference between a maximum emission wavelength of a fluorescence-emitting spectrum of the melt mixture and a maximum emission wavelength of a fluorescence-emitting spectrum of any of the first organic compound and the second organic compound is within ±10 nm, the first organic compound and the second organic compound are hosts used in a light-emitting layer containing a host and a light-emitting dopant. ### Claim 2 (depends on 1) The melt mixture for an organic electroluminescent device according to claim 1, wherein the first organic compound is represented by the following General Formula (1): wherein, X represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aromatic heterocyclic group having 3 to 17 carbon atoms or a linked aromatic group in which 2 to 8 of these aromatic rings are linked, Z represents an aromatic heterocyclic group represented by Formula (1a), the ring A is an aromatic hydrocarbon ring represented by Formula (1b), the ring B is a heterocycle represented by Formula (1c), and the ring A and the ring B are each fused to an adjacent ring at any position, R1's independently represent a cyano group, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or an aromatic heterocyclic group having 3 to 17 carbon atoms, Y represents O, S, or N—Ar1, Ar1 represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aromatic heterocyclic group having 3 to 17 carbon atoms, or a linked aromatic group in which 2 to 8 of these aromatic rings are linked, and a represents an integer of 1 to 3, b and c represent an integer of 0 to 4, and d represents an integer of 0 to 2. ### Claim 3 (depends on 2) The melt mixture for an organic electroluminescent device according to claim 2, wherein Y is N—Ar1. ### Claim 4 (depends on 1) The melt mixture for an organic electroluminescent device according to claim 1, wherein the second organic compound is represented by the following General Formula (2): here, Z represents O, S, or N—Ar3, and Ar2 and Ar3 represent an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aromatic heterocyclic group having 3 to 17 carbon atoms or a linked aromatic group in which 2 to 8 of these aromatic rings are linked, R2's independently represent a cyano group, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or an aromatic heterocyclic group having 3 to 17 carbon atoms, and e and h represent an integer of 0 to 4, and f and g represent an integer of 0 to 3. ### Claim 5 (depends on 4) The melt mixture for an organic electroluminescent device according to claim 4, wherein Z is N—Ar3. ### Claim 6 (depends on 4) The melt mixture for an organic electroluminescent device according to claim 4, wherein General Formula (2) is the following Formula (3): here, Ar2, Ar3, R2, e, h, f and g are the same as those in General Formula (2). ### Claim 7 (depends on 1) An organic electroluminescent device containing a sublimate obtained by vacuum-vapor-depositing the melt mixture for an organic electroluminescent device according to claim 1 in a light-emitting layer. ### Claim 8 (depends on 1) A method of producing an organic electroluminescent device, comprising a process in which the melt mixture for an organic electroluminescent device according to claim 1 is vacuum-vapor-deposited to form a light-emitting layer.