UV coating common faults and troubleshooting methods (9)

Nine, UV coating coating yellow

1, the phenomenon of failure

1UV Varnish raw material is impure and its color is dark.

2 Photoinitiator used in varnish has yellowing phenomenon.

3UV Varnish is stored for a long time and darkens.

4 Strong light source, long curing time, excessive exposure to ultraviolet light.

2, elimination method

1Selection of transparent and colorless UV varnish.

2 Avoid using photoinitiators that cause yellowing discoloration.

3 Adjust the speed of the light source to avoid overexposure.

4 If necessary, add a small amount of brightener.