Rubber composition for tyres incorporating a novel antioxidant system

Process for preparing a rubber composition based on at least one diene elastomer, a reinforcing filler, a crosslinking system and an antioxidant system, said process comprising the following steps:

• incorporating into a diene elastomer, in a mixer:
• a reinforcing filler;
• and
• an antioxidant system,
• by thermomechanically kneading the entire mixture, in one or more stages, until a maximum temperature between 110° C. and 190° C. is reached;
• cooling the entire mixture to a temperature below 100° C.;
• then incorporating a crosslinking system;
• kneading the entire mixture up to a maximum temperature below 110° C.,
• and being wherein said antioxidant system comprises at least two antioxidants “A” and “B”:
• A. an N-alkyl-N′-phenyl-para-phenylenediamine corresponding to the formula (I):
• B. a 4,4′-bis(alkylamino)triphenylamine corresponding to the formula (II):
• in which formulae, R1, R2 and R3, which are identical or different, each represent a linear or branched alkyl group having from 1 to 12 carbon atoms or a cycloalkyl group having from 5 to 8 carbon atoms, the A/B weight ratio being between 0.2 and 5.0.