Patent ID: 7622418

Claim:
A method for producing an exhaust gas purifying catalyst, which comprises the steps of: preparing a pre-crystallization composition containing elementary components, the elementary components constituting a perovskite-type composite oxide containing a noble metal; mixing the pre-crystallization composition with a powder of theta-alumina and/or alpha-alumina to prepare a mixture; and subjecting the pre-crystallization mixture to heat treatment whereby, the perovskite-type composite oxide containing the noble metal is supported on theta-alumina and/or alpha-alumina; wherein the perovskite-type composite oxide is represented by the general formula (1): AB 1-m N m O 3 (1) wherein A represents at least one element selected from rare earth elements and alkaline earth metals; B represents at least one element selected from Al and transition elements excluding the rare earth elements and noble metals; N represents at least one noble metal; and m represents an atomic ratio of N satisfying the following relation: 0<m<0.5; and wherein said method results in the perovskite-type composite oxide containing a noble metal supported on theta-alumina and/or alpha-alumina, and does not include adding further noble metal to said theta-alumina and/or alpha-alumina.