<p>Excess ink or an ink bleeding is removed by winding a band film (F), which is so provided as to be capable of being wound and unwound, around a trapping roller (11) installed opposite to a blanket (4) of a blanket wheel (3) through a contacting/retreating mechanism (12), thereby contacting the film (F) with the blanket (4). Consequently, it is possible to trap the ink by contacting always clean film with the blanket and also achieve the ink trapping with a simple mechanism for contacting and retreating the trapping roller.</p>
