Abstract: A tread for a heavy goods vehicle tire, the tread having a surface when new suitable for coming into contact with a road surface, this tread having a plurality of optimized incisions opening onto its tread surface when new, each incision made of at least two narrow portions and wide portions, each narrow portion surrounded by wide portions, the sum of the areas of narrow portions representing at least 40% of the total surface of the incision (and the width being less than 0.4 mm, each portion having a width at least equal to 0.4 mm, this tread being such that for each optimized incision each of the wide portions extending between two narrow portions includes at least one section inclined in a plane parallel to the mid-plane of the optimized incision, and forming an angle at least 15 degrees with the direction of the tread thickness.

Abstract: Mould for moulding a tread of a tire, this tread having a thickness of material to be worn away and a tread surface intended to come into contact with the road surface when the tire is running, this mould having a moulding surface intended to mould the tread surface of the tread, and having a moulding element formed of a blade and a bar, the blade being attached to the moulding surface to mould a sipe in the tread, the bar, borne by the blade to form an enlarged part of maximum width D, being intended to mould a channel in the tread, this channel itself being intended to form a new groove when the tread becomes part worn. Each blade is delimited by two lateral faces forming between them a mean angle of between 6° degrees and 18°. The blade width decreasing from the mould surface when new, as far as the connection with the bar, the blade width meets the bar being at least equal to between 0.2 and 0.4 times the maximum width D.

Abstract: Mould for moulding a tread of a tire, this tread having a thickness of material to be worn away and a tread surface intended to come into contact with the road surface when the tire is running, this mould having a moulding surface intended to mould the tread surface of the tread, and having a moulding element formed of a blade and a bar, the blade being attached to the moulding surface to mould a sipe in the tread, the bar, borne by the blade to form an enlarged part of maximum width D, being intended to mould a channel in the tread, this channel itself being intended to form a new groove when the tread becomes part worn. Each blade is delimited by two lateral faces forming between them a mean angle of between 6° degrees and 18°. The blade width decreasing from the mould surface when new, as far as the connection with the bar, the blade width meets the bar being at least equal to between 0.2 and 0.4 times the maximum width D.