Patent ID: 8387672
Filing Date: 2013-03-05
Classification: B29C,B29D,B29L,B60C,D06M,Y10T

Abstract:
1. A pneumatic tire comprised of an outer circumferential rubber tread, a supporting carcass containing an innermost carcass barrier rubber layer, and a rubber innerliner disposed inwardly from said supporting carcass and thereby inwardly from said carcass barrier rubber layer; wherein said tire has a built-in composite of polyurethane based sealant layer positioned between and adjacent to said carcass barrier rubber layer of said supporting carcass and said rubber innerliner; wherein said composite of polyurethane based sealant layer is a multilayered composite extending in a circumferential direction comprised of a thick polyurethane layer and a thin polyurethane layer with a thin intermediate layer positioned between said thick and thin polyurethane layers comprised of: a non-woven microfiber layer containing said polyurethane wherein said non-woven intermediate microfiber layer and is prepared by pouring a polyurethane precursor as a liquid reaction mixture over a non-woven microfiber layer and allowing a portion of the liquid reaction mixture to imbibe into and through said non-woven microfiber layer to form a thin polyurethane precursor layer beneath the polyurethane precursor-containing non-woven microfiber layer and a thicker polyurethane precursor layer on top of the non-woven microfiber layer and allowing the liquid reaction mixture to react at an elevated temperature to form a continuous semisolid polyurethane within the non-woven microfiber layer, thin semisolid polyurethane layer beneath the polyurethane-containing microfiber layer and a significantly thicker semisolid polyurethane layer on top of the microfiber layer, wherein said thicker layer of said polyurethane based sealant has a thickness in a range of from about 1 to about 8 millimeters (mm) and said thinner layer of said polyurethane based sealant has a thickness in a range of from about 0.1 to about 3 mm, so long as it is at least 2 mm thinner than said thicker polyurethane layer and said non-woven microfiber layer of said sealant composite has a thickness in a range of from about 0.01 to about 0.2 mm, and wherein said thin polyurethane layer of said multilayered sealant composite is positioned adjacent to said innerliner rubber layer.