| 摘要 |
PROBLEM TO BE SOLVED: To prevent a catalyst carrying layer from being peeled off, and improve the durability of an exhaust gas cleaning catalyst without increasing the amount of an oxide binder by making the average particle size of first particles smaller than that of second particles in the catalyst carrying layer containing the first and the second particle. SOLUTION: The catalyst bearing layer contains the first particle and the second particle and the average particle size of the first particle is constituted to be smaller than that of the second particle. That is, the average particle size of the first particle is at least about 0.1μm, and preferably as small as possible. The average particle size of the second particle is preferably at least twice the average particle size of the first particle. The mixing ratio of the first particle to the second particle is preferably at least about 1/20 of the total weight of the second particle. Further, it is desirable to use the first particle of at least 0.05 bulk density. For the first particle, silica particles such as silica, a silica alumina or zeolite are preferably used.
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