Why is Dot Loss an Issue in Gravure Printing and How Can It Be Resolved?

Dot Loss“ is one of the four major hazards in gravure printing. Here are the causes and solutions to this problem:

I. Plate Issues:

Use a plate cleaning agent to wipe the areas where dot loss occurs on the plate, which can solve dot loss caused by plate blockage. Religious book printing.

If wiping the plate doesn’t solve the problem, carefully examine the plate with a magnifying glass equipped with a light source to see if engraving or corrosion during plate making has caused dot defects. If there are defects in plate making, re-plating is necessary.

During plate making, analyze the original manuscript according to the equipment available in the printing plant and the printing materials used. shopping bag printing. If necessary, special treatment should be applied to the highlight areas prone to dot loss, commonly referred to as deepening.

If the wire lines on the plate are too thick or the gap between dots is too large, causing ink to spread unevenly during printing and resulting in dot loss, the plate needs to be remade to change the shape and angle of the dots.

II. Ink Issues:

High ink viscosity or yield stress leads to poor ink transfer. The solution is to reduce ink viscosity to ensure good ink leveling and improve ink wetting properties on the plate. catalog printing.

Ink drying too quickly and unevenly distributed on the plate, causing premature drying and solidification. The solution is to improve the initial drying of the ink, use slow-drying solvents, reduce ink drying speed, and increase dot gain.

No additional blowing treatment should be applied to the plate during the printing process.

Poor wetting between ink and plate (mismatched surface tension) makes it difficult for transferred ink to spread. printing in China. In this case, adjust the position of the doctor blade holder to shorten the distance between the doctor blade and the plate cylinder.

III. Plate Speed and Pressure:

When dot loss or unclear levels occur, increasing printing speed and adjusting printing pressure appropriately can solve the problem. book printing.

IV. Doctor Blade Issues:

If the doctor blade pressure is too high while the printing roller pressure is insufficient, adjust both the doctor blade pressure and the printing roller pressure accordingly.