Causes and Analysis of Dirty Faults in Various Kinds of Printing Plates

Water, ink roller failure caused the plate with dirty

(1) The fountain roller does not rotate due to mechanical or electrical failure.

(2) The pressure adjustment between the water transfer roller and the roller roller and the water roller is improper, causing unevenness in the upper water.

(3) The pressure adjustment between the water roller and the water roller and the printing is not in place, resulting in poor water impingement.

(4) The water fleece wrap of the watering roller is uneven, resulting in non-uniform printing water.

(5) The use of a long time, the dirty water roller, plush does not absorb water.

(6) Ink roller aging, ink absorption is uneven, resulting in dirty.

Printing process failure causes the plate to be dirty

　　 (1) The ink is too thin. Ink sticky ink is more difficult, the paper is easy to glue powder, the operator in order to print well, adding an excessive amount of ink, resulting in reduced cohesion of the ink, low viscosity, high fluidity and ink layer imprinting.

(2) In order to make the prints dry as quickly as possible, the operator believes that the more dry and dry the oil, the faster the ink will become thicker, more emulsified, more viscous, and more oily.

(3) The operator does not pay attention to the size of the layout water, the amount of water is too large, resulting in ink emulsification, resulting in floating in the blank area of ​​the printing plate.

(4) The ink volume is too large and the ink layer is too thick, which results in an imprinting expansion under the effect of extrusion.

(5) The amount of fountain solution is small, the acidity is small, and the hydrophilicity of the blank part of the printing plate is decreased.

Insufficient protection of PS plate caused the plate with dirty

(1) Plate cylinder and blanket cylinder, the pressure adjustment between the printing plate and the ink roller is too large, causing excessive wear of the plate, especially at the edge of the squeak.

(2) Severe decontamination of paper, operators do not pay attention to washing blankets, paper powder wear plates.

(3) After the blanket has collapsed, the blanket is overdone during the repair process, causing the repair site to be too high and to abrade the plate.

(4) The blanket loses its elasticity due to aging, and the printing plate is also susceptible to wear.

(5) The water should be wiped immediately when the machine is shut down for a short time. The operator neglects this work. Especially in the hot season, dust and other debris accumulate on the blank part of the dry printing plate, causing the printing plate to be dirty.

(6) When the protective rubber on the printing plate, there is a large amount of moisture on the rag. Over time, the printing plate is oxidized and dirty.

(7) When the operator repairs the plate with the correction fluid, the correction fluid that has not been promptly wiped solidifies on the plate, causing the plate to become dirty.

(8) The rag is not soft or has a hard object on it, causing scratches on the plate.

(9) The surface of the water fleece sleeve is covered with ink and reused. The above ink residue scratches the printing plate.