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

A light-emitting device comprising:

• an anode;
• a cathode;
• and
• an EL layer between the anode and the cathode,
• wherein the EL layer comprises a hole-injection layer, a light-emitting layer and an electron-transport layer,
• wherein the hole-injection layer comprises a first organic compound and a second organic compound,
• wherein the electron-transport layer comprises a third organic compound and a first substance,
• wherein the first organic compound comprises a cyano group or a halogen group,
• wherein the first substance is any of an alkali metal, an alkaline earth metal, an organic complex of an alkali metal or an alkaline earth metal, and a compound of an alkali metal or an alkaline earth metal,
• wherein a HOMO level of the second organic compound is higher than or equal to −5.7 eV and lower than or equal to −5.4 eV,
• wherein the third organic compound is an organic compound with an electron-transport property,
• wherein the electron-transport layer comprises a first region and a second region in a thickness direction,
• wherein an amount of the third organic compound in the first region is different from an amount of the third organic compound in the second region, and
• wherein the first region is closer to the anode than the second region is in the electron-transport layer.

A light-emitting device comprising:

• an anode;
• a cathode;
• and
• an EL layer between the anode and the cathode,
• wherein the EL layer comprises a first layer, a second layer, a third layer, a light-emitting layer, and a fourth layer in this order from the anode side,
• wherein the first layer is in contact with the anode,
• wherein the first layer comprises a first organic compound and a second organic compound,
• wherein the second layer comprises a third organic compound,
• wherein the third layer comprises a fourth organic compound,
• wherein the light-emitting layer comprises a fifth organic compound and a sixth organic compound,
• wherein the fourth layer comprises a seventh organic compound and a first substance,
• wherein the first organic compound comprises a cyano group or a halogen group,
• wherein the fifth organic compound is an emission center substance,
• wherein the first substance is any of an alkali metal, an alkaline earth metal, an organic complex of an alkali metal or an alkaline earth metal, and a compound of an alkali metal or an alkaline earth metal,
• wherein a HOMO level of the second organic compound is higher than or equal to −5.7 eV and lower than or equal to −5.4 eV,
• wherein electron mobility of the seventh organic compound is higher than or equal to 1×10−7 cm2/Vs and lower than or equal to 5×10−5 cm2/Vs when a square root of electric field strength [V/cm] is 600,
• wherein the fourth layer comprises a first region and a second region in a thickness direction,
• wherein an amount of the seventh organic compound in the first region is different from an amount of the seventh organic compound in the second region, and
• wherein the first region is closer to the anode than the second region is in the fourth layer.