Car tyre having a tread band comprising a central region, extending across an equatorial plane (X-X), and two shoulder regions (L2, L3), separated from the central region by two first circumferential grooves (2,3); - said central region having at least one central rib, comprising a plurality of central blocks, and at least two rows (9,10) of lateral blocks opposed to each other relative to said central rib and comprising a plurality of lateral blocks (31,32); - said central rib being axially delimited by two second circumferential grooves (4,5) and said plurality of central blocks being delimited by a respective plurality of first curvilinear grooves; - each first curvilinear groove extending between a second circumferential groove (4,5) and a circumferentially subsequent first curvilinear groove so as to form one of said central blocks; - the lateral blocks (31,32) of each row (9,10) of lateral blocks being separated from one another by means of a plurality of second curvilinear grooves distributed along the whole circumferential development of the tyre and having an extension equal to at least 95% of the width of the respective row (9,10) of lateral blocks; characterized in that: - each of said second curvilinear grooves comprises a substantially straight first segment inclined relative to a direction parallel to said equatorial plane (X-X) so as to form an angle θ greater than or equal to 45°, a substantially straight second segment (16") oppositely inclined relative to said first segment and a curvilinear connecting segment extending between said first and said second (16") segments; - said tread band further comprises a plurality of sipes (21,22,23,24,25) comprising a plurality of first sipes located in said central rib between said first curvilinear grooves and one of said second circumferential grooves (4,5). - said central region having at least one central rib, comprising a plurality of central blocks, and at least two rows (9,10) of lateral blocks opposed to each other relative to said central rib and comprising a plurality of lateral blocks (31,32); - said central rib being axially delimited by two second circumferential grooves (4,5) and said plurality of central blocks being delimited by a respective plurality of first curvilinear grooves; - each first curvilinear groove extending between a second circumferential groove (4,5) and a circumferentially subsequent first curvilinear groove so as to form one of said central blocks; - the lateral blocks (31,32) of each row (9,10) of lateral blocks being separated from one another by means of a plurality of second curvilinear grooves distributed along the whole circumferential development of the tyre and having an extension equal to at least 95% of the width of the respective row (9,10) of lateral blocks; characterized in that: - each of said second curvilinear grooves comprises a substantially straight first segment inclined relative to a direction parallel to said equatorial plane (X-X) so as to form an angle θ greater than or equal to 45°, a substantially straight second segment (16") oppositely inclined relative to said first segment and a curvilinear connecting segment extending between said first and said second (16") segments; - said tread band further comprises a plurality of sipes (21,22,23,24,25) comprising a plurality of first sipes located in said central rib between said first curvilinear grooves and one of said second circumferential grooves (4,5). - each of said second curvilinear grooves comprises a substantially straight first segment inclined relative to a direction parallel to said equatorial plane (X-X) so as to form an angle θ greater than or equal to 45°, a substantially straight second segment (16") oppositely inclined relative to said first segment and a curvilinear connecting segment extending between said first and said second (16") segments; - said tread band further comprises a plurality of sipes (21,22,23,24,25) comprising a plurality of first sipes located in said central rib between said first curvilinear grooves and one of said second circumferential grooves (4,5).