Process for producing a fresh wiping solution and for treating a used solution and apparatus for carrying out the process

A process for producing a fresh wiping solution comprising at least softened water and for treating the wiping solution contaminated by the inks of one or more intaglio printing machines, wherein said process comprises the following steps:

• (a) production of the fresh wiping solution,
• (b) introduction of the fresh wiping solution into one or more wiping tanks, where it is contaminated by the inks,
• (c) treatment of the used solution exiting from the wiping tank or tanks with a chemical agent, producing a solution and sedimented ink, said chemical agent being a copolymer having the following characteristics:
• relative density:
• 1.08 to 1.09 kg/dm3
• pH:
• 17
• molecular weight:
• 500,000
• Brookfield viscosity:
• 10,000 cPs,
• (d) separation by settling of the solution obtained in step (c), producing a clean solution and a concentrated solution with sedimented ink,
• (e) filtration of the concentrated solution, producing a clean solution and solid waste,
• (f) use of the clean solution obtained in steps (d) and (e) as fresh wiping solution.