Ink composition for organic EL thin film, and organic EL element

1. An ink composition for an organic EL thin film, the ink composition comprising:

an organic EL material;

a liquid crystalline compound having a bandgap of 3.5 eV or more; and

a solvent comprising an organic compound,

wherein the liquid crystalline compound is Cholesterol N-caprate (CC) as a cholesteric liquid crystal.

2. The ink composition for an organic EL thin film according to claim 1 , wherein the liquid crystalline compound contains no functional group of —CN, —OH, or —F.

3. The ink composition for an organic EL thin film according to claim 1 , wherein the liquid crystalline compound has a molecular dipole moment of 4.0 debyes or less.

4. An organic EL element comprising a light-emitting layer formed by the use of the ink composition for an organic EL thin film according to claim 1 , wherein the organic EL element comprises an organic EL material and a liquid crystalline compound.

5. An organic EL element comprising:

a pair of a positive electrode and a negative electrode; and

a light-emitting layer sandwiched between the positive electrode and the negative electrode, wherein the light-emitting layer comprises an organic EL material and a liquid crystalline compound having a bandgap of 3.5 eV or more, and

wherein the liquid crystalline compound is Cholesterol N-caprate (CC) as a cholesteric liquid crystal.

6. The organic EL element according to claim 5 , wherein the liquid crystalline compound contains no functional group of —CN, —OH, or —F.

7. The organic EL element according to claim 5 , wherein the liquid crystalline compound has a molecular dipole moment of 4.0 debyes or less.