US 12,295,255 B2
Light-emitting device, light-emitting appliance, display device, electronic appliance, and lighting device
Takahiro Ishisone, Kanagawa (JP); Nobuharu Ohsawa, Kanagawa (JP); and Satoshi Seo, Kanagawa (JP)
Assigned to Semiconductor Energy Laboratory Co., Ltd., (JP)
Appl. No. 17/436,734
Filed by Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken (JP)
PCT Filed Feb. 24, 2020, PCT No. PCT/IB2020/051517
§ 371(c)(1), (2) Date Sep. 7, 2021,
PCT Pub. No. WO2020/183264, PCT Pub. Date Sep. 17, 2020.
Claims priority of application No. 2019-042551 (JP), filed on Mar. 8, 2019.
Prior Publication US 2022/0190246 A1, Jun. 16, 2022
Int. Cl. H01L 51/00 (2006.01); C09K 11/06 (2006.01); G06F 3/041 (2006.01); H01L 51/50 (2006.01); H10K 85/30 (2023.01); H10K 85/40 (2023.01); H10K 85/60 (2023.01); H10K 50/11 (2023.01); H10K 50/13 (2023.01); H10K 101/10 (2023.01); H10K 101/30 (2023.01); H10K 101/40 (2023.01)
CPC H10K 85/633 (2023.02) [H10K 85/346 (2023.02); H10K 85/40 (2023.02); H10K 85/622 (2023.02); H10K 85/636 (2023.02); H10K 85/654 (2023.02); H10K 85/6572 (2023.02); H10K 85/6574 (2023.02); H10K 50/11 (2023.02); H10K 50/13 (2023.02); H10K 2101/10 (2023.02); H10K 2101/30 (2023.02); H10K 2101/40 (2023.02)] 13 Claims
 
1. A light-emitting device comprising a first light-emitting layer and a second light-emitting layer between a pair of electrodes,
wherein the first light-emitting layer includes a first material and a second material,
wherein the first material has a function of converting triplet excitation energy into light emission,
wherein the second material has a function of converting singlet excitation energy into light emission and includes a luminophore and five or more protecting groups,
wherein the luminophore is a condensed aromatic ring,
wherein the five or more protecting groups each independently have any one of an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, and a trialkylsilyl group having 3 to 12 carbon atoms,
wherein light emission is obtained from the second material,
wherein the second light-emitting layer includes a third material and a fourth material,
wherein the third material has a function of converting singlet excitation energy into light emission, and
wherein a triplet excitation energy level of the fourth material is lower than a triplet excitation energy level of the third material.