| abstract |
An electron transporting layer is a cured layer including carbon atoms, nitrogen atoms and oxygen atoms. When ratios of the number of carbon atoms, ratios of the number of nitrogen atoms, and ratios of the number of oxygen atoms are analyzed at 10 points by an X-ray photoelectron spectroscopy (ESCA), the respective standard deviations, σ(C), σ(N) and σ(O), of the ratios of the number of carbon atoms, the ratios of the number of nitrogen atoms and the ratios of the number of oxygen atoms satisfy the following expressions (1) to (3): n σ(C)≦1.5 (1),n n σ(N)≦1.5 (2),n n and n σ(O)≦1.5 (3). |