Light-emitting device, light-emitting apparatus, display device, electronic appliance, and lighting device

A light-emitting device comprising:

• a light-emitting layer between a pair of electrodes,
• wherein the light-emitting layer comprises a first material and a second material,
• wherein the first material is a platinum-based organometallic complex or metal complex, and has a five-membered ring skeleton,
• wherein the second material is capable of converting singlet excitation energy into light emission and comprises a luminophore and at least four protecting groups,
• wherein the luminophore is a condensed aromatic ring or a condensed heteroaromatic ring,
• wherein the four protecting groups are not directly bonded to the condensed aromatic ring or the condensed heteroaromatic ring,
• wherein the four protecting groups each independently comprise any one of an alkyl group having 3 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, and
• wherein an emission peak of the first material overlaps with an absorption band on the longest wavelength side of the second material.

A light-emitting device comprising:

• a light-emitting layer between a pair of electrodes,
• wherein the light-emitting layer comprises a first material and a second material,
• wherein the first material is a platinum-based organometallic complex or metal complex, and has a five-membered ring skeleton,
• wherein the second material is capable of converting singlet excitation energy into light emission and comprises a luminophore and two or more diarylamino groups,
• wherein the luminophore is a condensed aromatic ring or a condensed heteroaromatic ring,
• wherein the condensed aromatic ring or the condensed heteroaromatic ring is bonded to the two or more diarylamino groups,
• wherein aryl groups in the two or more diarylamino groups each independently comprise at least one protecting group,
• wherein the protecting groups comprise any one of an alkyl group having 3 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, and
• wherein an emission peak of the first material overlaps with an absorption band on the longest wavelength side of the second material.