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.
