Method for controlling the water volume of printing layout

Correctly controlling the water consumption of the layout is an important means to maintain the correct balance of ink and water. The following objectives can be achieved:

(1) Keep the ink and water in the correct balance on the layout to ensure that the graphic area and blank area of ​​the printing plate are relatively stable.

(2) The ink can maintain good transfer performance and spread evenly on each printing surface.

(3) Reduce ink emulsification, and the ink can be dried in a timely manner.

There are many factors that affect the water consumption of the layout, but the general principle is: the water consumption needs to be determined according to the amount of ink contained in the graphics and text of the layout. Usually determined according to the following conditions:

1. Distribution of graphic and text areas on the layout

The area and distribution of the graphics on the printing plate vary from manuscript to manuscript. The graphic area and water consumption should conform to the law of "big ink and large water, small ink and small water". The amount is small; the distribution of graphics and texts is dense, the amount of ink loaded is large, and the water consumption is large; the distribution of graphics and texts is sparse, the amount of ink loaded is small, and the water consumption is small; the distribution of graphics and texts is asymmetrical, and the water consumption is locally controlled.

2. Properties of paper

The surface strength, smoothness, tightness, water resistance (sizing degree), water content, etc. of the paper are the main conditions for determining the water consumption of the layout, and are often controlled and adjusted accordingly with changes in these properties. The general water consumption is: the surface strength of the paper is good, the water consumption is small, and vice versa; the smoothness is high, the water consumption is small, and vice versa; If the water content is high, the water consumption will be small, and vice versa, it will be large; if the water content is high, the water consumption will be small, and vice versa.

The above-mentioned water use rules also need to be controlled and adjusted according to the actual situation in the production process.

3. The nature of the ink

To determine the water consumption of the layout, the water resistance and emulsification value of the ink are the main conditions. But these two conditions are determined by many factors. Generally, there are the following relationships: good water resistance, small water consumption, and vice versa, large emulsification value, large water consumption, and vice versa; high viscosity, small water consumption, vice versa; large fluidity (thin ink), water consumption Large, otherwise small; resin-based inks have high water resistance, are not easy to emulsify, and consume less water; oil-based inks have low water resistance, are easy to emulsify, and consume more water; pigments with high dispersion (small particles) require less water, and vice versa .

4. Machine speed

The running speed of the machine is inversely proportional to the water consumption of the layout, that is, the higher the machine speed, the smaller the water consumption of the layout; the slower the machine speed, the greater the water consumption of the layout.