A pneumatic tire is provided with, in the tread surface, land portions that include a rib or a plurality of blocks. The land portions are provided with a plurality of narrow shallow grooves and a plurality of recessed portions in a contact patch. Additionally, the opening area ratio Sc of the recessed portions in the central portion region in the tire lateral direction of one continuous contact patch and the opening area ratio Se of the recessed portions in the end portion regions in the tire lateral direction have the relationship Se<Sc, where the central portion region is defined as the region in the central portion in the tire lateral direction occupying 50% of the continuous contact patch of the land portions, and the end portion regions are defined as the regions in the left and right end portions in the tire lateral direction occupying 25%.

A method of forming a tire includes a mold having a molding cavity defined at least in part by an outermost molding surface and a pair of opposing shoulder-forming portions. The mold includes a sipe-forming element spaced apart inwardly from the pair of opposing shoulder-forming portions with a knife edge oriented towards a first shoulder-forming portion and a knife edge translation member arranged outside the mold cavity and configured to translate in a direction towards the first shoulder-forming portion and from which a sipe-forming portion extends. The method further includes arranging an uncured tire tread within the mold, molding the uncured tire tread, and demolding the tire tread such that the sipe-forming element forms a sipe by the knife edge lacerating a thickness of the cured molded tread as the sipe-forming element is pulled in a direction toward the shoulder-forming portion.

The disclosed pneumatic tire includes a plurality of circumferential main grooves and is configured to be mounted in a specified vehicle mounting direction. On the tread surface, an inner shoulder land portion does not substantially include a groove, and has only one or more inner circumferential sipe extending in the tread circumferential direction and a plurality of inner widthwise sipes extending in the tread width direction, and an outer shoulder land portion has a plurality of widthwise grooves communicating with the circumferential main groove and the tread edge and extending in the tread width direction and an outer widthwise sipe located between the widthwise grooves adjacent in the tread circumferential direction and extending in the tread width direction.

The present invention includes tire treads having a plurality of sipes (14) where at least one of the opposing sides of the sipe thickness includes a plurality of projections (18, 36) and recesses (20, 38) and a method for forming the same.

The present invention includes tire treads having a sipe (18) and a void feature (22) in fluid communication with the sipe. Particular embodiments of the present invention also include methods for forming the same. In various embodiments, the sipe has a length, a height, and a thickness that is variable across the length and height of the sipe. The thickness of the sipe includes a thick portion (24) and a thin portion (26), the thick portion at least partially extending around a perimeter of the thin portion. In particular embodiments, the void feature (22) which is in fluid communication with the sipe extends primarily in a direction of the sipe length and has a width extending in the direction of the sipe thickness equal to or greater than substantially 1 millimeter.

Provided in a tread portion of a tire are main grooves, lug grooves intersecting the main grooves, and land portions defined by the main grooves. A specific one of the land portions includes, in a ground contact surface, sipes and narrow grooves intersecting the main grooves, the narrow grooves having a depth of 1.50 mm or less. When extending from one side toward another side in the width direction, the sipes and the narrow grooves have different directions extending in the circumferential direction in the central region and have the same direction extending in the circumferential direction in both edge regions on an outer side from the central region in the width direction. The specific one of the land portions includes at least one land portion on the outer side in the width direction.

A tread for a tire includes: a first tread zone extending circumferentially, continuously, and entirely around the tire, the first tread zone being formed of a first compound; a second tread zone extending circumferentially, continuously, and entirely around the tire, the second tread zone being formed of a second compound different from the first compound; and a boundary groove axially separating the first tread zone from the second tread zone, the first tread zone, the second tread zone, and the boundary groove entirely forming the tread, the boundary groove having an axial centerline disposed an axial distance from an equatorial plane of the tire. The first tread zone has a first circumferential groove and a sidewall portion defining an intermediate circumferential rib of the first tread zone and a shoulder circumferential rib of the first tread zone.

A tread for a tire includes: a first tread zone extending circumferentially, continuously, and entirely around the tire, the first tread zone being formed of a first compound; a second tread zone extending circumferentially, continuously, and entirely around the tire, the second tread zone being formed of a second compound different from the first compound; and a boundary groove axially separating the first tread zone from the second tread zone, the first tread zone, the second tread zone, and the boundary groove entirely forming the tread, the boundary groove having an axial centerline disposed an axial distance from an equatorial plane of the tire. The first tread zone has a first circumferential groove and a sidewall portion defining an intermediate circumferential rib of the first tread zone and a shoulder circumferential rib of the first tread zone.

Embodiments include a tire tread having a plurality of tread elements and a plurality of lateral discontinuities arranged along the tread width and tread length, each of the plurality of tread elements being spaced apart by one of the plurality of lateral discontinuities. The tread width is divided into a plurality of regions, the plurality of regions including: (1) a pair of outermost regions, each outermost region being arranged closest to one of the pair of opposing lateral sides of the tread, and (2) at least one centermost region is arranged closest to the longitudinal centerline of the tread. Each of the lateral discontinuities have a thickness, where the thickness of one or more of the lateral discontinuities arranged in each of the outermost regions is smaller than the thickness of one or more of the lateral discontinuities arranged in the centermost region.

In particular embodiments, a tire tread includes one or more lateral sipes (26s) arranged within the tread (20). As each such lateral sipe (26s) extends outward from within the tread thickness (T20) and towards the outer, ground-engaging side (22) of the tread (20), the lateral sipe (26s) is inclined towards the intended direction (R) of tire rotation. The lateral sipe (26s) also has a width (W26) (thickness) configured to, at an unworn stage, close along at least a portion of the sipe depth during operation of a loaded tire, and being configured to, at a worn stage, remain open during operation of the loaded tire. The lateral sipe (26s) has a width-to-height ratio associating the sipe width (W26) to the sipe height, the width-to-height ratio equaling 1:10 to 1:40. Providing a plurality of these lateral sipes (26s) may result in improved consistency of tread wear performance over the life of the tread (20).