A digital printing module for printing a band of continuous sheet material comprising: a chassis supporting one or more rotary rollers rotative about parallel roller axes, said rollers defining an arcuate band path in which a band of sheet material is supported and guided in a taut manner and conveyed in a direction of conveyance; a plurality of digital printing units, supported in the chassis, each provided with ink-jet print heads which are arranged opposite, adjacent, and orthogonal to a printing segment of the band of sheet material when in a printing position, wherein the printing segment of each printing unit determines a perpendicular direction perpendicular thereto, a longitudinal direction tangent thereto and parallel to the direction of conveyance, and a transverse direction tangent thereto and perpendicular to the direction of conveyance; each printing unit includes one bridge provided with guides and a carriage slidable along said guides in the transverse direction, said carriage containing at least the ink-jet print heads of said printing unit, said guides having a length greater than the width of the band path, one part of each guide overlapping the band and another part of said guide projecting horizontally beyond a vertical projection of the band path, wherein the slidable carriage connected to said guides is movable from the printing position to a maintenance position in which the ink-jet print heads are arranged in a position non-opposed to the band path, on one side of the printing segment; characterized in that each bridge includes a first anchoring point attached to the chassis by means of an adjustment device and includes a second anchoring point attached to the chassis by means of an articulation or by means of another adjustment device, the first anchoring point and the second anchoring point being spaced apart in the transverse direction, and wherein each adjustment device can be independently controlled and includes a mechanism causing a movement of the corresponding first or second anchoring point of the bridge with respect to the chassis in the perpendicular direction, and/or in the transverse direction and/or in the longitudinal direction, thereby modifying the distance and inclination of each ink-jet print head placed in the printing position with respect to other ink-jet print heads placed in the printing position and with respect to the corresponding printing segment to correct printing imperfections. a chassis supporting one or more rotary rollers rotative about parallel roller axes, said rollers defining an arcuate band path in which a band of sheet material is supported and guided in a taut manner and conveyed in a direction of conveyance; a plurality of digital printing units, supported in the chassis, each provided with ink-jet print heads which are arranged opposite, adjacent, and orthogonal to a printing segment of the band of sheet material when in a printing position, wherein the printing segment of each printing unit determines a perpendicular direction perpendicular thereto, a longitudinal direction tangent thereto and parallel to the direction of conveyance, and a transverse direction tangent thereto and perpendicular to the direction of conveyance; each printing unit includes one bridge provided with guides and a carriage slidable along said guides in the transverse direction, said carriage containing at least the ink-jet print heads of said printing unit, said guides having a length greater than the width of the band path, one part of each guide overlapping the band and another part of said guide projecting horizontally beyond a vertical projection of the band path, wherein the slidable carriage connected to said guides is movable from the printing position to a maintenance position in which the ink-jet print heads are arranged in a position non-opposed to the band path, on one side of the printing segment; characterized in that each bridge includes a first anchoring point attached to the chassis by means of an adjustment device and includes a second anchoring point attached to the chassis by means of an articulation or by means of another adjustment device, the first anchoring point and the second anchoring point being spaced apart in the transverse direction, and wherein each adjustment device can be independently controlled and includes a mechanism causing a movement of the corresponding first or second anchoring point of the bridge with respect to the chassis in the perpendicular direction, and/or in the transverse direction and/or in the longitudinal direction, thereby modifying the distance and inclination of each ink-jet print head placed in the printing position with respect to other ink-jet print heads placed in the printing position and with respect to the corresponding printing segment to correct printing imperfections.