Patent ID: 6880600
Filing Date: 2005-04-19
Classification: B60C,C08L

Abstract:
1. A tire for motor vehicles bearing heavy loads comprising: (a) a carcass ply based on metal cords and an elastomeric carcass layer coating said cords, (b) an inner elastomeric layer which defines the radially inner face of said tire, thereby circumscribing the inner space of the tire, and which protects the carcass ply from diffusion of air coming from the inner space of the tire, and (c) an intermediate reinforcement layer located between said carcass ply and said inner layer, said intermediate reinforcement layer being formed from a composition comprising: (i) a natural or synthetic polyisoprene having a majority of chains with cis-1,4 bonds and a solution copolymer of one or more conjugated diene monomers and one or more vinyl aromatic monomers, wherein said copolymer is a solution SBR copolymer in an amount that is at least 50 phr and said solution SBR copolymer simultaneously satisfies the following relationships: wherein D is the amount of diene chains having a 1, 2 bond content (in %) and VA is the amount of vinyl aromatic chains (in %), and (ii) carbon black, in an amount of 25 to 85 parts by weight per hundred parts of said elastomer (phr), wherein said carbon black has values of DBP oil absorption (in ml/100 g) and of BET specific surface area (in m