Print can be removed by scratching the surface. Print fails adhesion tape, rub or wrinkle tests.
Causes:
– Wrong ink used for substrate;
– Ink over-thinned;
– Wrong or weak solvent mixture used;
– Insufficient heat or drying applied;
– Insufficient or over treatment of substrate surface;
– Surface contamination of film by additives;
– pH too low.
Solutions:
– Ensure the correct ink is being used for the substrate;
– Use correct viscosity and ensure ink film weight by using reducing medium;
– Ensure correct solvent mixture to give good ink film forming and wetting of substrate;
– Increase heat and air volume. Some inks need to be fused to the substrate coating;
– Check the treatment level of substrate. If low, very high or variable, contact supplier,
– Try wiping and washing an area and printing. A primer wash coat may assist.
– Ensure pH is correct.
