How to Observe and Control Surface Moisture

Water is an integral part of offset printing. In actual production, the layout must have a certain amount of water in order to ensure the quality of printed products. In practice, I summarized the following methods for observing and controlling surface moisture.

First, observe the layout and ink roller

1. In normal printing, the water reflection on the layout is bright and dark. If the water reflection on the surface is bright, it indicates that the moisture is large and the water supply needs to be reduced.

2. If the ink roller does not deposit ink during printing, it indicates that the printing surface is too watery.

3. If there is no ink or no ink on both sides of the ink fountain roller, it means that the water is large.

Second, observe the print

1. After looking for a good ink color and printing 100 sheets, if the ink color changes greatly, it means that the moisture is large.

2. The printed product has a water point, indicating that the water is large.

3. Observe the reduction status of the printed product outlets. If the outlets are actual, then the moisture control can be used. If the outlets are weak, the moisture content is large (excluding pressure, ink roller, ink, paper and other factors).

4. If the ink color of the first few dozens of prints is darker than the normal print ink, it indicates that the moisture control can be used; if the ink color is lighter or less than the normal print ink, the water is large (excluding the ghosting factor).

The premise of the above conclusion is that the printing plate must meet the control requirements of printing and printing standards, and the proofs meet the normal requirements.