The ink produced a lot of bubbles during the printing process. What happened?

【Chinese Packaging Network News】 Printing process ink in the ink tank produces a lot of bubbles, these bubbles attached to the plate cylinder, so that part of the dots on the pattern disappeared, white spots will appear on the prints. Why bubbles in the ink? This article analyzes one by one for reference.

1. The surface tension of the ink is strong, which is greatly affected by the resin and solvent used in the ink. Sometimes the viscosity of the ink is large and bubbles are easily generated.

2, ink tank or circulation device is defective. A lot of air bubbles are caused by poor ink flow in the ink tank or the circulation pump. When ink is used to recycle the ink, the ink flows from the ink tank to the circulation drum, and bubbles are formed in the ink due to the drop and the agitating action of the plate cylinder at high speed.

3. On the direct ink supply printing machine, the magnetic ink stir bar bends and beats in the ink tank to cause bubbles.

4, add an appropriate amount of defoamer. Although there are special defoamers, but too much on the nature of the ink has an adverse effect, improper use but will cause bubbles, so can not be used.