Process and system for the production of books with digital printing and respective book

A system for manufacturing books printed on cut sheets, comprising a perforating equipment for longitudinal and transversal perforations of the cut sheets, a transversal cutting equipment, a transversal folding equipment, a longitudinal folding equipment and a stacking device, wherein each book comprises a number of signature groups, each formed with a given number of basic sheets, said basic sheets are parts of respective signature sheets forming the signature groups and said signature sheets are constituted by the cut sheets, said cut sheets are arranged in a stack for different books and in which the transversal folding equipment and, if requested, the longitudinal folding equipment are actuatable for transversal and longitudinal folds of the signature sheets, said system further comprising a program such to:

• a) identifying in said signature groups a reduced signature group including a number of sheet sections having at least a page with text and/or figures, for a book in which the part regarding a last signature group has at least a sheet section of the last signature sheet devoid of text and/or figures of the book to be manufactured;
• b) actuating the perforating equipment for perforating the signature groups and, if present, the reduced signature group in weakening lines provided for the folds of the signatures;
• c) actuating the transversal cutting equipment for cutting a last sheet of the signature sheets so as to separate, as reduced signature sheet, the sheet section or the sheet sections having at least a page with text and/or figures;
• d) processing the reduced signature sheet for a signature with reduced number of sheets by actuating the transversal folding equipment limited to the sheet sections having at least a page with text and/or figures or skipping the actuation of the transversal folding equipment for a single sheet section;
• e) actuating, if requested, the longitudinal folding equipment for longitudinal folding or leaving longitudinally unfolded the reduced signature sheet, as signature with reduced number of sheets;
• and
• f) stacking the signature with reduced number of sheets on the other signatures for completing a basic book block of the book to be manufactured.