US Patent 7977276 Exhaust gas purifying catalyst and method of producing the same

Disclosed is an exhaust gas purifying catalyst exhibiting excellent purification performance for a long period of time by suppressing coagulation of a noble metal. A catalyst powder comprises a noble metal and first and second compounds. In the catalyst powder, the first compound carries the noble metal and is separated from another first compound carrying a noble metal by the second compound. At least one catalyst layer comprising the catalyst powder is formed on an inner surface of a substrate. The catalyst layer has fine pores. A fine pore volume of fine pores having a fine pore diameter of greater than 0.1 μm to less than or equal to 1 μm is 10% to 60% of the fine pore volume of fine pores having a pore diameter of 1.0 μm or less.