Abstract: The machine comprises a horizontal transfer line (2) formed by mutually parallel rubber-coated rollers underneath and tangent to a horizontal plane on which the sheet (L) to be processed travels, which sheet is advanced, by the rollers driven by suitable means (3, 4, 104, 5), in a predetermined and constant direction (F), two of these rollers (102, 202) being designed as opposing rollers for corresponding parallel applicator rollers (17, 19) above them, the latter rollers being driven by suitable means (18, 20) and having differing characteristics enabling them to perform two different painting operations, in one of which the applicator roller (17) rotates in the same direction and with the same speed of advance as the sheet, and in the other of which the applicator roller (19), also referred to as the reverse-type roller, rotates in the opposite direction to the direction of advance of the sheet and at an adjustable speed.