To provide an ignition catalyst having high ignitionability, a reforming catalyst which realizes ignition more reliably, and an ignition element even in a region where the concentration of gaseous mixture distributed is lean, and an internal combustion engine thereof.
The ignition catalyst is arranged in a combustion chamber 1 of the internal combustion engine and ignites the fuel-air gaseous mixture when the gaseous mixture comes in contact with the ignition catalyst. The reforming catalyst is arranged in the combustion chamber of the internal combustion engine and modifies the fuel-air gaseous mixture into reformed gas having heat conductivity higher than oxygen when the gaseous mixture comes in contact with the reforming catalyst. The ignition element carries the ignition catalyst 2 on a fire-resistant inorganic oxide. The fire-resistant inorganic oxide is hexaaluminate. The internal combustion engine includes the ignition catalyst 2 or the ignition element 3 in a prechamber provided separately from a main chamber in the combustion chamber 1. In the internal combustion chamber, superlean fuel is burned in the main chamber, using flame obtained by igniting the fuel-air mixture in the prechamber.
KANEKO HIROAKI
MIYAZAKI KIYOSHI
MATSUMOTO MASAHARU