US Patent 10960389 Exhaust gas purification catalyst

An exhaust gas purification catalyst of the present invention is provided with a base 10 and a catalyst coat layer 30. The catalyst coat layer is provided with Rh and Pd as noble metal catalysts. Herein Rh is disposed in a first-stage upper layer A and a second-stage upper layer C, and Pd is disposed in the first-stage upper layer A and a first-stage lower layer B, and in a second-stage lower layer D. A mass ratio (APd/ARh) of Pd to Rh, disposed in first-stage upper layer A is 0.5≤(APd/ARh)≤3.