Process factors: Although the type of press, the imprinting method, and the plate “target="_blank†are different, the process factor is the common cause of static electricity.
Extrusion and frictional electrification It is known that friction can actuate electricity. In a two-revolution, one-rotation, etc. flexographic press, the paper rotates with the drum, the plate and the platen reciprocate, and the printing is performed by the roll pressure when the roller comes into contact with the printing plate. The paper is strongly pressed by the printing plate and the roller. The machine runs at high speed, and the printing plate and the ink are violently rubbed. The brush removes dust and impurities from the paper and causes the paper to cling to the surface of the roller. It also rubs against the paper. There is a lot of static electricity.
Contact and peel off the power.
In printing, the paper quickly contacts and separates from the paper strip, the guide wheel, and the ink. In particular, the paper is bitten by the gripper teeth and rapidly wraps around the surface of the cylinder. After printing, the paper is quickly peeled from the surface of the drum. The surface of the drum is lined with blankets, cotton cloth, kraft paper, etc., and static electricity is generated on the printed paper and the drum liner.
Effect of speed on static electricity.
When the printer runs at a high speed, the friction between paper and ink increases, and the amount of static electricity increases.
Equipment and raw materials factors:
The non-metallic parts of the printing press rub against each other, the surface resistance is high, and the electrostatic charge cannot be quickly released. Some printed paper has generated static electricity during the papermaking process.
Some paper and lining surfaces are rough and stained with dirt, and they are extremely prone to static electricity, causing difficulties for the subsequent processes.
envirnmental factor:
The air temperature and humidity of the printing shop have a significant impact on printed static electricity. When the temperature rises, the number of charged particles generated by the press parts and the material when they are pressed against each other increases, so that the body and the material are charged. The higher the temperature, the more the accumulated charge is. Humidity and temperature affect each other. The increase in temperature will make the air become dry, and the humidity in the space will decrease accordingly. The number of charged particles will correspondingly accelerate and increase, and the electricity will accumulate more.