Multicolor light emission apparatus and manufacturing method thereof

A multicolor light emission apparatus comprising:

• a first organic EL element having a first maximum emission wavelength in a blue light wavelength region and a second organic EL element having a second maximum emission wavelength longer than the first maximum emission wavelength,
• wherein the first organic EL element comprises a first light emission layer containing a first host and a first dopant, a first hole transporting layer containing a first compound, which is provided adjacent to one side of the first light emission layer, and a first electron transporting layer containing a second compound, which is provided adjacent to another side of the first light emission layer, and the second organic EL element comprises a second light emission layer containing a second host and a second dopant, a second hole transporting layer containing a third compound, which is provided adjacent to one side of the second light emission layer, and a second electron transporting layer containing a fourth compound, which is provided adjacent to another side of the second light emission layer, and
• wherein the maximum emission wavelength of the first and second hosts is not longer than 415 nm, the maximum emission wavelength of the first compound and the maximum emission wavelength of the third compound are not longer than 415 nm and are the same, and the maximum emission wavelength of the second compound and the maximum emission wavelength of the fourth compound are not longer than 415 nm and are the same.

A method of manufacturing a multicolor light emission apparatus, the apparatus comprising:

• a first organic EL element having a first maximum emission wavelength in a blue light wavelength region;
• and
• a second organic EL element having a second maximum emission wavelength longer than the first maximum emission wavelength;
• wherein the first organic EL element comprises a first light emission layer containing a first host and a first dopant, and the second organic EL element comprises a second emission layer containing a second host and a second dopant, and
• wherein each of the first and second hosts has an emission wavelength region which is shorter than the blue light wavelength region;
• and the method comprising the steps of
• simultaneously forming the hole transporting layer of each of the organic EL elements,
• separately forming the light emission layer of each of the organic EL elements, and
• simultaneously forming the electron transporting layer or the hole blocking layer of each of the organic EL elements.