SELF-SEALING PNEUMATIC TIRE

An uncured pneumatic tire and a method of manufacturing a pneumatic rubber tire having a puncture sealing feature is disclosed. The uncured pneumatic tire comprises a generally toroidal-shaped supporting carcass (4, 14, 24) with an radially outer circumferential tread (8, 11, 28), two spaced beads (5, 15, 25), at least one ply extending from bead to bead, sidewalls (3, 13, 23) extending radially from and connecting said tread to said beads, and a sealant layer (7, 17, 27) which is disposed radially inwardly from the supporting carcass (4, 14, 24). The sealant layer (7, 17, 27) is located (i) radially between two layers of an innerliner (6, 16) or (ii) radially between said supporting carcass (4, 14, 24) and a radially inner containment layer (26) or (iii) radially between an innerliner layer (6, 16) and a containment layer (26). The circumferential tread (8, 11, 18) is adapted to be ground-contacting. The sealant layer (7, 17, 27) is encapsulated by a relatively stiff composition, wherein the relatively stiff composition is configured to break down at temperatures used for tire vulcanization and to form a sealant material, wherein the relatively stiff material does not interfere with the function of surrounding tire components, and wherein the sealant layer (7, 17, 27) comprises a relatively low viscosity material that preferably requires only little or no depolymerization to act as a sealant material.