1, screen printing ink old printing is not clean.

2, solvent drying speed is too fast (printing speed and solvent evaporation speed does not match).

3. Dry hot air blows to the layout.

4, scraper and layout of the contact point and imprint ink dust, moisture, bubbles and other miscellaneous curing, the transfer rate of ink will decrease due to the decrease of the actual amount of ink in the net hole, some coarse particles will even embedded in the net hole.

5, plate - making electroengraving accuracy and Angle of net hole will also shadow.

6, to the transfer of ink, resulting in insufficient or lost dot.

7, the quality of the printing ink and solvent is one of the causes of the blocking version, if ink liquidity is not good, the printing ink has been spoiled or mixed with different series of high viscosity, printing ink, used the inappropriate solvent or solvent ratio, even add solvent ink when improper operation, will affect the ink metastatic, cause plugging.