Curing

Problem:

Ink film too heavy.

Solution:

Run thinner ink film / strengthen ink. (Normally not a problem with EB).

______________________________________________________________________

Problem:

Ink is over-emulsified.

Solution:

Run thicker ink film / weaken ink (often associated with light take-off/coverage). Check fountain solution pH and conductivity or reduce dampener feed. Consult your Sun Chemical representative (Reference Ink Emulsification topic later in this Troubleshooting Guide).

______________________________________________________________________

Problem:

Improper inerting has occurred.

Solution:

Check O2 level on meters. Check nitrogen knives for proper angle and flow rate. Increase flow of nitrogen. Check to ensure knives are free of obstructions (EB only).

______________________________________________________________________

Problem:

UV exposure is inadequate.

Solution:

Replace lamps as needed. Clean or replace reflectors as needed. Check focal point of lamps (UV only).

______________________________________________________________________

Problem:

Substrate has contamination.

Solution:

Check substrate for oils or any other contaminants inhibiting cure.

______________________________________________________________________

Problem:

Press speed is too fast.

Solution:

Check that press speed does not exceed UV lamp capability; may require additional lamps to increase speed. With EB, ensure that dose has remained at the same level as it was at lower speed.