Abstract: The present invention relates to an adhesive usable at ambient temperature to bond together two cross-linked rubber compositions, to a process for preparing the adhesive, to a tread of a tire cover and to such a cover comprising this adhesive, and to an article comprising two parts bonded together by means of this adhesive. An adhesive based on a copolymer comprising urea or urethane and isocyanurate groups wherein the copolymer is a reaction product of: (a) a polyisocyanate comprising isocyanurate groups, the polyisocyanate having a functionality equal to or greater than three, (b) a functional polymer comprising an amine or alcohol group at each of its chain ends, the functional polymer being selected from the group consisting of polyether diamines, polyether diols, polyester diols and (ester-ether) diol copolymers, and (c) at least one trimerization catalyst capable of forming isocyanurate groups from isocyanate groups, wherein the molar ratio of isocyate groups to amine is between 1.5 and 2.2.

Abstract: The present invention relates to an adhesive usable at ambient temperature to bond together two cross-linked rubber compositions, to a process for preparing the adhesive, to a tread of a tire cover and to such a cover comprising this adhesive, and to an article comprising two parts bonded together by means of this adhesive. An adhesive based on a copolymer comprising urea or urethane and isocyanurate groups wherein the copolymer is a reaction product of: (a) a polyisocyanate comprising isocyanurate groups, the polyisocyanate having a functionality equal to or greater than three, (b) a functional polymer comprising an amine or alcohol group at each of its chain ends, the functional polymer being selected from the group consisting of polyether diamines, polyether diols, polyester diols and (ester-ether) diol copolymers, and (c) at least one trimerization catalyst capable of forming isocyanurate groups from isocyanate groups, wherein the molar ratio of isocyate groups to amine is between 1.5 and 2.

Abstract: A molding element intended to equip a mold for molding, in a tread made of a rubber compound, a non-demoldable pattern, the element including at least one part molding a part of a pattern with an undercut. The molding element is one wherein during at least part of the demolding operation, the projected area of each part molding a pattern with an undercut onto a plane perpendicular to the demolding direction is smaller than the area of the same part projected onto the same plane in the molding position, so as to make demolding of the molding element easier.