Frequently Asked Technical Questions about Printing

In printing production, common technical problems mainly focus on two aspects: print defects (such as wrinkles, smearing) and process stability (such as ink transfer, registration). The causes are mostly related to the coordination of materials, equipment, environment and process parameters. Here is an overview of common problems and their causes in several major categories:

Special issues with different printing methods

Different printing processes have their own unique technical difficulties. Understanding these differences can help locate problems faster:

Pad printing: The core lies in the cooperation of the silicone head, steel plate etching depth, and ink. Common problems include air bubbles (blisters), which may be caused by etching that is too deep/too shallow, or the wrong shape of the rubber head; stringing is often caused by the ink drying too quickly or the viscosity being too high.

Silk screen printing: Most of the problems are related to screen printing and squeegee. For example, screen clogging is often caused by large ink particles, too fast drying or powder loss from the substrate; burrs on the edges of graphics and text are mostly related to too low mesh mesh and poor exposure.

Offset/flexo printing: Pay more attention to ink balance and pressure. For example, wrinkles in printed matter are often caused by changes in the moisture content of the paper or uneven pressure on the rollers; smearing on the back is often caused by improper pH value of the fountain solution or excessively thick ink layer, which causes the drying to be too slow.

Systematic troubleshooting ideas

When dealing with printing problems, it is recommended to follow the idea of ​​"from outside to inside, from simple to complex", which will help solve problems efficiently:

Check the materials and environment: Confirm whether the printing substrate (paper, plastic) is damp or the surface treatment is in place, and verify whether the temperature and humidity of the workshop are stable (usually recommended temperature is 23℃±3℃ and humidity is 50%±5%).

Check the process parameters: Confirm whether the ink viscosity, drying speed, and diluent ratio meet the process requirements. Especially in pad printing, the diluent evaporation speed is a key variable.

Check equipment and consumables: Verify whether the printing pressure is uniform, whether the printing plate (or steel plate) is worn, and whether the rubber head (or squeegee) is aged and deformed.