Electroluminescence display device
Embodiments disclosed herein relate to an electroluminescence display device including a first electrode, a second electrode facing the first electrode, an emission layer between the first electrode and the second electrode, and a bank layer defining the emission layer. The bank layer may be disposed between the first electrode and the second electrode. The bank layer may include a first bank layer and a second bank layer. The second bank layer may include a black pigment. The first bank layer may be closer to the first electrode than the second bank layer, and the first bank layer may have a lower permittivity than the second bank layer.
1. An electroluminescence display device comprising:
a first electrode;
a second electrode facing the first electrode;
an emission layer between the first electrode and the second electrode; and
a bank layer defining the emission layer, the bank layer between the first electrode and the second electrode, the bank layer including a first bank layer and a second bank layer, the second bank layer including a black pigment, the first bank layer closer to the first electrode than the second bank layer, the first bank layer having a lower permittivity than the second bank layer.
2. The electroluminescence display device of claim 1 , wherein the first bank layer includes the black pigment.
3. The electroluminescence display device according to claim 1 , wherein the second bank layer has more black pigments than the first bank layer.
4. The electroluminescence display device according to claim 1 , wherein the second bank layer has a higher refractive index than the first bank layer.
5. The electroluminescence display device according to claim 1 , further comprising:
a spacer on a surface of the bank layer away from the first electrode.
6. The electroluminescence display device according to claim 5 , wherein the spacer is formed of a transparent material or including the black pigment.
7. An electroluminescence display device comprising:
a first electrode on a substrate;
a bank layer on the first electrode, the bank layer including at least a first bank layer and a second bank layer, the first bank layer being closer to the first electrode and having a lower permittivity than the second bank layer to reduce leakage current;
a second electrode on the bank layer; and
an emission structure between the first electrode and the second electrode.
8. The electroluminescence display device according to claim 7 , wherein the second bank layer adjacent to the second electrode includes a black pigment to increase an optical density of the second bank layer.
9. The electroluminescence display device according to claim 8 , wherein the first bank layer adjacent to the first electrode includes the black pigment.
10. The electroluminescence display device according to claim 9 , wherein a weight % of the black pigment in the first bank layer is smaller than that of the black pigment in second bank layer to suppress an increase in the permittivity of the first bank layer.
11. The electroluminescence display device according to claim 7 , wherein when a light of 400 Knit is incident at an incident angle of 45 degrees, a reflection luminance is 30 nit or less at a reflection angle of 30 degrees.
12. The electroluminescence display device according to claim 7 , wherein the permittivity of the first bank layer is 7 C/m 2 (Coulomb/m 2 ) or less.
13. The electroluminescence display device according to claim 8 , wherein the optical density of the second bank layer is 4 or less.