A print image treatment device is formed of a supply device for holding an excess ink removing liquid, the excessive ink removing liquid not dissolving in a printing ink forming a print image and having a lower surface tension than that of the printing ink; a rotating contact member having an outer surface, on which the excessive ink removing liquid is supplied from the supply device; a facing member situated under the contact member for nipping and carrying a printing sheet between the contact member and the facing member, an excessive printing ink forming the print image on a printing sheet being transferred to the excessive printing ink removing liquid when the printing sheet contacts the contacting member; a cleaning device contacting the contact member for removing the excessive printing ink with the excessive ink removing liquid; and a separation device receiving the excessive ink removing liquid with the excessive printing ink. The excessive ink removing liquid is separated from the printing ink having been transferred from the printing sheet. The separation device includes a filter having the thickness and air-flow resistance indicated below: 0.05