Factors affecting gloss quality issues

Paper performance

The effect of paper on glazing quality is mainly reflected in the influence of paper smoothness on glazing quality. High smoothness paper has a significant effect after glazing, while low smoothness paper or paperboard has a poor effect after glazing, because the varnish is absorbed by the rough surface of the paper or cardboard. In order to solve this problem, the casein base can be applied once before glazing, or glazing twice.

temperature

The glazing temperature is between 18-20 ℃, which can achieve the most ideal effect. In winter, the glazing oil is easy to solidify, and the bright film on the surface of the glazing product is uneven. In order to solve this problem, the varnish needs to be stored in a warm place. If the temperature of the varnish is too low, it must be properly diluted with solvents.

Printing ink

The printing inks used in products that need to be glazed after printing must have solvent resistance and heat resistance, otherwise the printed graphics will be discolored or wrinkled. The solution is to pay attention to the following points when selecting printing inks: ① Use inks that are resistant to alcohols, esters, and acids and alkalis. ②Use inks that do not change color for a long time and have good gloss. ③ Choose inks that have good adhesion to paper.

Print Crystallization

The phenomenon of crystallization of prints is mainly due to the fact that the prints have been placed for too long, the area of ​​the bottom ink of the prints is too large, and too much oil is added. The crystallization of the ink film on the surface of the paper often makes the varnishes not go up or produce "Flower face", "pitching" and other phenomena. In order to solve this problem, 5% lactic acid is generally added to the glazing oil, which can be used after stirring. This modified varnish is applied to the printed matter, and the vitreous crystal film on the surface of the printed matter is destroyed, so that the varnish can be evenly applied to the surface of the printed matter to form a bright film.