| abstract |
A higher purification performance of HC, CO, and NOx is obtained in a transition period in which an exhaust gas temperature is changed from a low temperature to a high temperature. The A second catalyst layer 3, an average particle diameter D 50 of the following Ce-containing binder particles 13a 50 nm moistened with an average particle diameter D 50 of less 50 nm Ce-free binder particles 13b, the second catalyst In at least a part of the layer 3, these content ratios were changed. [Selection] Figure 2 |