Abstract: Keyless lithographic printing system with single printing fluid. A lithographic printing press has a blanket cylinder (101) and a plate cylinder (102) with a printing plate (100) mounted thereon, a form roller system (103) having at least one form roller rotationally contacting the plate cylinder (102), a printing fluid supply system for supplying a controlled composition of printing fluid to the form roller system (103). A reservoir system (110, 124, 126, 107, 128) is provided for containing the printing fluid, the printing fluid being a predetermined composition of dampening water and ink. A pickup roller (106) removes the printing fluid from the reservoir system, the pickup roller (106) having an oleophilic and hydrophobic surface. A drum roller (104) transfers the printing fluid to the form roller system (103), the drum roller (104) having an oleophilic and hydrophobic surface and interfacing with the form roller system (103).

Abstract: A system for the continuous and automatic supply of a mixture of ink and dampening fluid to a lithographic press. The ink and dampening fluid are mixed and then pumped to the press fountain. The fluid mixture is sampled downstream from the mixing location and a signal is sent to control feed of ink and dampening fluid to the mixing location to ensure that the desired ratio of ink to water is maintained.