Patent ID: 11910628
Assignee: MERCK PATENT GMBH
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  C | IPC C  H

Claim 0:
1. An organic electroluminescent element, comprising:
a luminescent film and a layer adjacent to the luminescent film,
wherein the luminescent film comprises a material of the layer adjacent to the luminescent film,
the luminescent film comprises a host compound, a blue phosphorescent compound, and a blue fluorescent compound,
an emission spectrum of the blue phosphorescent compound and an absorption spectrum of the blue fluorescent compound have portions overlapping with each other;
shortest wavelength-side maximum emission wavelengths of the blue phosphorescent compound (abbreviated as “BPM” in the expression) and the blue fluorescent compound (abbreviated as “BFM” in the expression) satisfy the following expression (1):

λBFM≥λBPM  expression (1)

wherein λBFM represents the shortest wavelength-side maximum emission wavelength of the blue fluorescent compound and λBPM represents the shortest wavelength-side maximum emission wavelength of the blue phosphorescent compound; and
light emission derived from the blue fluorescent compound is detected.