Printing ink and printing environment control

Control of the printing environment We have already seen the importance of controlling ink performance during the printing process. However, to print quality prints that meet quality requirements, all changes must be controlled. This starts with the adjustment of the pad printer and the ink.

Many changes occur to the pad printer and the ink during the inking, squeegeeing, ink sucking, and image transfer. Each step in pad printing is different in some respects, so pay special attention when adjusting the pad printer. In order to obtain the required printing results for each adjustment, it is necessary to control the environmental conditions and the printing machine. Speed, etch depth and etch quality of gravure printing, hardness and resilience of the print head.

With the required printing speed and the necessary minimum head pressure adjustment, the next issue to consider is the printing environment.

The temperature and relative humidity in the printing shop may change every day. The study found that the best printing environment is: temperature between 20 °C ~ 22 °C, and relative humidity between 50% ~ 60%. However, in the real work environment, we rarely achieve such an optimal working environment. Changes in temperature and relative humidity can significantly affect the entire printing process, so it is necessary to minimize the impact of environmental factors on the printing process.

If there are no environmental control facilities in the pressroom and in the workshops that store materials such as inks, substrates, additives, and printheads, here are some ways to minimize environmental change issues during the printing process:

(1) Keep the machine and material away from the walls of the room. The room is near the wall where the temperature changes are more pronounced. The change in temperature here during the day or in the season is relatively large.

(2) Do not expose the machine and materials to direct sunlight, and avoid the hot air and cold air from the air conditioner directly blowing into the machine and material.

(3) The ink, print head, catalyst, and substrate to be used in the same batch of printing jobs are stored in the same place. If there is no such condition, these materials should be put into the printing shop several hours before printing. In this way, inks, substrates, etc. can be adapted in advance to the environment of the printing shop, avoiding some printing problems. Because the material suddenly drops from a hot environment to a colder environment, an agglomeration reaction occurs, and the moisture in the substrate also changes greatly.