Irregular “donut” shaped white spots surrounding a small spot of ink.
| CAUSE | CURE |
|---|---|
| Dried Ink Particles. | Avoid dry ink “skin” when removing from kits or cans, clean press thoroughly and remove all dried ink. Prevent ink from drying up on ends of rollers by lubrication and/or manual washing. Filter ink if being pumped from totes or drums. |
| Rubber roller is breaking down and releasing particles. | Recondition rollers and replace if necessary. |
| Excessive glaze buildup is breaking away from rollers. | Use a good glaze remover to clean rollers, or scrub rollers with pumice powder and solvent to remove glaze. |
| Breakdown of dampener rollers or sleeves due to wear. | Replace suspect roller or sleeve in dampening unit. |
| Foreign particles, dirt, and debris falling into press. | Clean the areas above the press, wash up press, and clean plates. |
| Loose paper dust, fibers, and coating on web. | Vacuum the web of paper, run the web through a dead unit, or consult paper supplier. |
| Too tacky of ink picking apart the surface of the paper. | Reduce tack of ink, consult paper supplier for better paper stock. |
| Blanket becoming tacky and picking the surface of the paper, rubber is being reverted. | Wash blanket with a rubber rejuvenator or replace blanket. |