Light-emitting element, light emitting device, and electronic device

A light-emitting element comprising:

• a first light-emitting layer between an anode and a cathode;
• and
• a second light-emitting layer between the anode and the cathode, the second light-emitting layer being in contact with a cathode side of the first light-emitting layer,
• wherein the first light-emitting layer includes a first layer provided on an anode side and a second layer provided on a cathode side,
• wherein the first layer provided on the anode side contains a first organic compound and a first light-emitting substance,
• wherein an amount of the first light-emitting substance in the first layer provided on the anode side is greater than or equal to 50 wt % and less than 100 wt %,
• wherein the second layer provided on the cathode side contains a second organic compound and the first light-emitting substance,
• wherein an amount of the second organic compound in the second layer provided on the cathode side is greater than or equal to 50 wt % and less than or equal to 99.9 wt %,
• wherein the second light-emitting layer contains a third organic compound and a second light-emitting substance,
• wherein an amount of the third organic compound in the second light-emitting layer is greater than or equal to 50 wt % and less than or equal to 99.9 wt %, and
• wherein the first organic compound is a compound different from the second organic compound.

A light-emitting element comprising:

• a first light-emitting layer between an anode and a cathode;
• a second light-emitting layer between the anode and the cathode, the second light-emitting layer being in contact with a cathode side of the first light-emitting layer,
• wherein the first light-emitting layer includes a first layer provided on an anode side and a second layer provided on a cathode side,
• wherein the first layer provided on the anode side contains a first light-emitting substance and a first organic compound,
• wherein the first light-emitting substance has a hole-transporting property,
• wherein an amount of the first light-emitting substance in the first layer provided on the anode side is greater than or equal to 200/3 wt % and less than 100 wt %,
• wherein the second layer provided on the cathode side contains a second organic compound and the first light-emitting substance,
• wherein an amount of the second organic compound in the second layer provided on the cathode side is greater than or equal to 50 wt % and less than or equal to 99.9 wt %,
• wherein the second light-emitting layer contains a third organic compound and a second light-emitting substance,
• wherein an amount of the third organic compound in the second light-emitting layer is greater than or equal to 50 wt % and less than or equal to 99.9 wt %, and
• wherein the first organic compound is a compound different from the second organic compound.

A light-emitting element comprising:

• a first light-emitting layer between an anode and a cathode;
• and
• a second light-emitting layer between the anode and the cathode, the second light-emitting layer being in contact with a cathode side of the first light-emitting layer,
• wherein the first light-emitting layer includes a first provided on an anode side and a second layer provided on a cathode side,
• wherein the first layer provided on an anode side contains a first light-emitting substance and a first organic compound,
• wherein the second layer provided on the cathode side contains a second organic compound and the first light-emitting substance,
• wherein an amount of the second organic compound in the second layer provided on the cathode side is greater than or equal to 50 wt % and less than or equal to 99.9 wt %,
• wherein the second light-emitting layer contains a third organic compound and a second light-emitting substance,
• wherein an amount of the third organic compound in the second light-emitting layer is greater than or equal to 50 wt % and less than or equal to 99.9 wt %,
• wherein the first organic compound is a compound different from the second organic compound,
• wherein the first layer has a hole-transporting property higher than the second layer,
• wherein the second layer has an electron-transporting property higher than the first layer, and
• wherein a thickness of the second layer is smaller than a thickness of the first layer.