How to master the balance between ink and ink is a difficult point in the offset printing process. Here's a summary of some of the lessons I learned in my long-term work.
Practice has proved that when the layout of water is too large, the ink on the printed sheet correspondingly reduced, on the contrary, if the layout of the water is too small, then reduce the amount of ink to adjust to a new balance, so that the depth of the ink remains consistent.

We know that if the water is too small, the blank part will be dirty, and the water is too large, it will affect the printing quality. In this regard, I summarized the following points:

1. To hinder the normal transmission of ink, the formation of imprint empty false;
2. Ink color is uneven, especially before and after printing;
3. Increase the deformation of the paper will make the overprint not allowed;
4. The paper absorbs excess water, causing curling and uneven delivery;
5. Wet the drum pad or make the drum shell not flush;
6. Due to ink dimming, the picture is dry, the outline is not visible, and the color is old;
7. Decrease in ink strength, and sometimes have to increase the amount of ink, so that outlets become ambiguous, the level is unclear, resulting in water and large ink phenomenon;
8. Imprinting color changes greatly, resulting in color error of the sample;
9. The imprint gloss is reduced, and the drying speed is also slowed down;
10. Accelerate the deinking of the ink roller, and the ink will become large, which will cause the printing surface to be dirty and will also cause the back of the printed sheet to be stained.

It can be seen that the amount of water used is one of the important signs of technical proficiency. Under normal circumstances, the minimum amount of water should be kept when the ink and water balance is within the lowest range. However, it cannot be stipulated mechanically that the amount of water used depends on the speed of the machine, the area of ​​the layout, the nature of the paper, and the thickness of the imprinted ink layer.

The water consumption of the control layout should be based on the premise that the layout can not afford to be dirty. Whether the amount of water in the layout can be correctly identified is a necessary condition for the control of water consumption. At present, the identification of the amount of water is usually based on experience and needs repeated exploration.

Here are some signs of more water:

1. The in-rolling "points" of the lower string ink roller and the transfer roller accumulate into droplets;
2. Imprint ink is light, it is not easy to deepen the ink color after adding ink;
3. The ink roller surface has a lot of ink, but the amount of blotting ink is not deep;
4. Before and after the interruption of printing, there is a big difference in ink color;
5. Compared with the original paper, the printed sheet is weak;
6. The edge of the paper is curled downward and the paper is not evenly distributed.
7. The imprinting of imprints on the seal sheet and the edge imprinting with large blank area have wavy voids;
8. Eraser and plate cylinder liners are wetted with moisture;
9. Other phenomena of "great water and ink".

Through daily observation and analysis, we can promptly identify various phenomena of excessive water consumption and control them to ensure the quality of printed products.