| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst for cleaning an exhaust gas, in which sintering of a noble metal being an active species, lowering of the specific surface area of a material for supporting the noble metal, or the like can be suppressed even at a high temperature condition (e.g. a high temperature position at directly below an exhaust manifold) and which keeps a good level in the cleaning performance to NOx, HC and CO under such a condition that A/F fluctuates in the wide range at driving a vehicle, even in the case where the use amount of the noble metal is reduced in comparison with the conventional use amount. SOLUTION: The catalyst for cleaning the exhaust gas is obtained by applying a catalyst layer on an integrated structure-type carrier having a cell cross section of a polygon through an under coat layer comprising an inorganic oxide. The inorganic oxide is alumina, and catalytically active components in the catalyst layer are platinum and/or rhodium. The ratio (Lmax./Lmin.) of the maximum thickness (Lmax.) of the catalyst layer at the corner of a cell to the minimum thickness (Lmin.) of the catalyst layer at the flat part of the cell is adjusted to be in the range of 1 to 10, and the thickness of the catalyst layer is controlled to be in the range of 5 to 200 μm. |
