One of the key factors in extending plate life is cleaning and maintenance. Proper plate care not only prolongs optimal print quality, but also saves money and the inconvenience that comes with damaged plates.
Dixie Graphics Business Development’s Jay Gieske recently gave a presentation to a group of industry peers at an regional FTA Southeast networking event, held at our facility.
FLEXO PLATE CLEANING
Timing is an important element to plate cleaning and its effectiveness. Plates should be cleaned immediately after printing, using a soft nylon horsehair bristle brush along with a compatible wash-up solution to loosen and remove dried ink deposits, and a lint-free cloth to blot up excess cleaning solvent. Because dried ink deposits become more difficult to remove, and may require harsh scrubbing, make sure ink is washed off before it dries. Firm bristle brushes are not advised, as they can snag on fine copy and cause damage to the plate. Furthermore, it’s not a good idea to allow plates to soak in the plate cleaner for more than 30 minutes. The reason here is that even acceptable cleaners can affect plates if kept in contact with the plate print surface for extended periods of time. Among the “Do nots” with regard to chemical use in cleaning plates > Gasoline, Kerosene, Acetone, Ketone, Toluene, Xylene, or any other “tone” or “ene” are not advised and can damage plates.
Some of the recommended flexo plate cleaning solvents and solutions include:
• Ethyl Alcohol
• Butyl Cellosolve
• Diacetone Alcohol
• Isopropyl Alcohol
• Methyl Cellosolve
• n-Propyl Alcohol
• Specific Solutions or Cleaning Machines (commercially available)
FLEXO PLATE STORAGE
Ensure the cleaned plate is completely dry before storage, and aree stored flat whenever possible. Ideal storage for plates is in black untreated poly and laid flat in a drawer or on a shelf. If plates must be stacked, it is important to place foam between plates, never stacking plates directly on top of each other to store. If plates must be stored on sleeves or cylinders wrap plates with Saran Wrap and black poly. to prevent delaminating as well as to protect plates from overexposure to light. Plates should always be protected from UV light, white incandescent or fluorescent light, window light, and sunlight. UV filters are recommended in plate storage area.
It should be noted that plates stored on sleeves or cylinders are more susceptible to ozone attack and cracking due to the constant stress on the plate, thus it’s not a good idea to store plates near areas of high ozone concentration (corona discharge units, electrical equipment, arc lamps, etc.). The temperature of the plate storage area should range between 40-85° F, and away from heat sources, heating vents,etc. Humidity does not usually affect plate life on solvent washed sheet polymer, and no special precautions are necessary in the storage area. In the case of water washed polymer, check with manufacturer for specific requirements.
Disclaimeer > It is always best to consult with your plate provider (How can we help?) on the best cleaning, storage and maintenance for your specific plates. For more information on this topic, contact Jay Gieske at JGieske@DixieGraphics.com or by calling 615-620-3678.