Problems and solutions in UV offset printing process (SIX)

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Problems and solutions in UV offset printing process (SIX)
Analysis and solution of smearing on the back of printed matter
1. The pH value of the fountain solution is too high. The pH value of the fountain solution beneficial to printing should be between 4.3-5.5. A pH value higher than 5.5 will reduce the drying speed of the ink. It will cause the back side to smudge.
Adjustment method:
A certain amount of acid can be added to the fountain solution to reduce the PH value of the fountain solution.
2. The viscosity of the ink is not too low, resulting in excessive fluidity. During printing, the page attracts the ink into a paste and causes the page to get dirty. At the same time, it will affect the ink drying speed and cause the back side to get dirty.
Adjustment method: appropriately adjust the amount of ink oil or select ink with high viscosity.
3. The ink layer on the printing plate surface is too thick or the amount of boosting agent is inappropriate when adjusting the ink, which slows down the ink drying speed and causes the back side to smudge.
Adjustment method: Add appropriate amount of desiccant and anti-sticking agent to the ink to speed up the drying speed.
4. The ink is not dry well or the amount of ink is too large.
Adjustment method: Add appropriate amount of desiccant and anti-sticking agent to the ink, or appropriately reduce the amount of ink without affecting the ink color of the printed matter.

Problems and solutions in UV offset printing process (SIX)

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