EXHAUST PURIFICATION CATALYST

摘要

The present invention addresses the problem of providing an exhaust purification catalyst that has durability against stress factors such as high temperature and against poisonous substances, and is capable of exhibiting sufficient purification performance even under a high Ga condition. The present invention relates to an exhaust purification catalyst having two or more catalyst coating layers on a base material. The present invention has improved gas diffusibility of an underlying catalyst coating, which is present under the uppermost catalyst coating layer, due to the underlying catalyst coating having a structure with many voids, with a certain portion or more of all the voids comprising pores having a high aspect ratio of 5 or more.