Tubeless pneumatic tire with carcass having butyl-based inner topping rubber layer

A tubeless pneumatic tire free of an inner liner comprising:

• a carcass comprising a plurality of carcass plies stacked one on the other, radially of the tire, each of said carcass plies having a carcass cord web and topping rubber layers unified with the carcass cord web on opposite sides thereof by calendering, said plurality of carcass plies including an innermost carcass ply extending from the tread portion through the sidewall portion to the bead portion and turned up around the bead core outwardly from the inside of the tire in the axial direction, a chafer covering the turned-up portion of said innermost carcass ply, and a reinforcing rubber layer interposed between the turned-up portion of the innermost carcass ply and said chafer;
• wherein:
• only the topping rubber layer defining an interior surface of the tire of the innermost carcass ply is formed of a butyl-based rubber, thereby eliminating the inner liner, and
• the topping rubber layers other than the topping rubber layer defining the interior surface of the tire are formed of a diene-based rubber material.