Use and adjustment of letterpress printing inks

In the letterpress printing process, the following factors are closely related to the quality of the printed ink. Correctly understanding and understanding the relationship between these factors and ink color is of great significance for accurately controlling the quality of printed ink.

Correctly adjust and use ink

In general, when the temperature is lower, the ink appears thicker and its fluidity is poor, which may cause poor transfer and unevenness. This should be based on the characteristics of the printed matter, and the additives should be used to appropriately dilute the ink so as to maintain good Liquidity and transfer effect to keep the ink uniform. If the ink is adjusted too thin, the ink of the print will appear light. The adjustment of the ink flowability should fully consider the characteristics of the printing press speed and the structure of the ink feed. If the speed is fast, the length of the ink path, and the number of ink rollers are large, then due to the large coefficient of friction, the ink tends to become thin and light. Therefore, the above situation should be fully taken into account when adjusting the ink, and the printability of the ink can be reasonably adjusted. In addition, in the preparation of inter and mixed color inks, it should try to avoid the use of a large proportion of ink mixing. In order to avoid the ink in the ink fountain due to the difference in the weight of the printing, “delamination” (precipitation and suspension) phenomenon occurs, and the color difference of the printing is made.

Turn off the good operation technology

First, it is necessary to pay attention to the reasonable maintenance of the machine, and usually to maintain the feeder and air pump maintenance, so that the mechanical parts and components to maintain a good use of the state, so that the air flow is unobstructed, the printing sheet to send smooth;

Secondly, according to the thickness and size of the printed sheets, the feeders, air pumps, and parts related to the transport of paper should be adjusted to ensure the normal transport of printed sheets;

Thirdly, we must make necessary adjustments to the printability of paper, such as the process of paper shaking and knocking, so that the paper transport eliminates the phenomenon of adsorption and adhesion, and maintains a certain degree of stiffness so as to facilitate smooth paper feeding. At the same time, it can better avoid the occurrence of empty sheets, multiple sheets, and paper feed skew;

Fourth, we must turn off the stacking paper operation technology. If the paper stack is not even, we must take measures to carry out the leveling treatment in a timely manner so that there is no obvious difference in height. Through these measures, the control is ensured to maintain the continuity of the paper feed, so as to prevent print chromatic aberration caused by parking.