ARTICLE, IN PARTICULAR A PNEUMATIC TYRE, HAVING AN EXTERNAL RUBBER MIXTURE COMPRISING A LANTHANIDE SALT
This invention relates to an article, in particular a pneumatic tire for a vehicle, comprising at least one external rubber mixture, in particular a tread, said external mixture comprising a rubber mixture consisting of at least one diene elastomer such as BR, SBR or NR, a reinforcing filler such as silica, a crosslinking system such as a vulcanization system, between 0.2 and 10 pce of an antioxidant, for example a substituted paraphenylenediamine, and between 0.2 and 10 pce of a lanthanide acetylacetonate such as a neodymium actylacetonate. The latter makes it possible to advantageously reduce the consumption of antioxidant during the thermal oxidizing aging of the composition and hence of the external mixture.
1 - 15 . (canceled)
16 . An article comprising an external portion formed of at least a rubber mixture, wherein the rubber mixture includes:
at least a diene elastomer,
a reinforcing filler,
a crosslinking system,
between 0.2 and 10 phr of an antioxidant, and
between 0.2 and 10 phr of lanthanide acetylacetonate,
where “phr” corresponds to parts by weight per hundred parts of elastomer.
17 . An article according to claim 16 , wherein the diene elastomer is chosen from a group of elastomers that includes polybutadienes, natural rubbers, synthetic polyisoprenes, butadiene copolymers, isoprene copolymers, and mixtures thereof.
18 . An article according to claim 16 , wherein the reinforcing filler is chosen from a group of fillers that includes carbon blacks, inorganic fillers, and mixtures thereof
19 . An article according to claim 16 , wherein the reinforcing filler is silica, a carbon black, or a mixture of silica and a carbon black.
20 . An article according to claim 16 , wherein an amount of the reinforcing filler is between 30 and 150 phr.
21 . An article according to claim 16 , wherein the crosslinking system is based on sulphur and an accelerator.
22 . An article according to claim 16 , wherein an amount of the lanthanide acetylacetonate is between 0.3 and 6 phr.
23 . An article according to claim 22 , wherein the amount of the lanthanide acetylacetonate is within a range from 0.5 to 4.0 phr.
24 . An article according to claim 16 , wherein the lanthanide is chosen from a group of rare earth metals that includes lanthanum, cerium, praseodymium, neodymium, samarium, erbium, and mixtures thereof.
25 . An article according to claim 24 , wherein the lanthanide is neodymium.
26 . An article according to claim 16 , wherein the antioxidant is chosen from a group that includes substituted p-phenylenediamines, substituted diphenylamines, substituted triphenylamines, quinoline derivatives, and mixtures thereof.
27 . An article according to claim 16 , wherein the antioxidant is chosen from a group of diamines that includes substituted p-phenylenediamines and mixtures thereof.
28 . An article according to claim 16 , wherein an amount of the antioxidant is between 0.3 and 6 phr.
29 . An article according to claim 16 , wherein the article is a tyre.
30 . An article according to claim 29 , wherein the external portion formed of the rubber mixture is a tread of the tyre.