1. Viscosity and drying rate of ink
In order to scrape the excess ink from the surface of the plate cylinder, the scraper must penetrate the ink film, so when the ink viscosity is high, it needs a larger scraper pressure. Therefore, we should try to reduce the viscosity of the ink in order to reduce the pressure of the scraper.
2. Influence of hard sand, dust and other impurities
If there are hard particles in the ink, when scraping, the plate cylinder is easily scratched by hard particles, which will affect the quality of printing products, or cause the plate cylinder to be scrapped. In addition, the substrate surface impurities also easily mixed into the ink, accumulated over a long period of time, also easy to cause damage to the plate cylinder, so try to keep the substrate and ink clean is often necessary. In order to remove foreign matters, the ink in the ink tank can be filtered regularly or the metal mesh can be inserted into the ink recycling system for continuous filtration. Whether the dust in the environment falls into the ink or adsorbs on the impression cylinder, it will directly damage the scraper and the layout.
3. The corrosiveness of ink
Some inks, such as black ink, are corrosive to the plate cylinder, so they should be cleaned in time after use.