Gradation print unevenness can be divided into gradual grade uneven print and shallow print uneven.
Gradation level print unevenness is mainly because no matter how you select the engraving process in the plate making process, you cannot hide the area where the dots are easy to produce parallel levels. Although the viscosity can be changed during the printing process, the level of the parallel zone can be changed. It is impossible to avoid the occurrence of a tiered network. Therefore, it is very difficult to control the unevenness of print quality in the production process. It is advisable to reduce the unequal printing unevenness due to the parallel level phenomenon by choosing a better engraving process during plate making.
The shallow print unevenness is mainly caused by the following reasons:
First, it is a group of knife-shaped unevenness caused by high ink viscosity or excessive evaporation speed of the solvent during the printing process.
Second, it is the viscosity of the ink in the printing process that is too low, which results in uneven printing of the prints in the laminate printing process, resulting in uneven printing.
Third, it is rough printing plate cylinder, with burrs, resulting in uneven scraping scraper.
Therefore, for the shallow print unevenness, the following solutions can be adopted: properly reduce the solvent's volatilization rate, increase the slow-drying solvent; appropriately increase the temperature of the printing shop, reduce the temperature of the printing shop; select better quality ink and plate cylinder .
Reprinted from: empiresoft.net