Processing and protection of the printing plate before the machine

What is the purpose of rubbing the plate?

Since the hydrophilic surface of the printing plate is a high-energy surface, it is easy to adsorb impurities and damage the hydrophilicity of the surface, so appropriate protection measures must be taken on the surface of the printing plate. Apply the protective gel to the printing plate. The lipophilic graphic part is not viscose because it is a low-energy surface and does not need to be protected. The hydrophilic blank part of the adhesive, the high-energy surface of the metal is replaced by the low-energy surface of the polymer compound, so that the adsorption of impurities in the blank portion of the printing plate is greatly reduced, and the surface of the printing plate is protected, which is The purpose of rubbing glue. The protective gel is a hydrophilic, reversible colloid that not only protects the blank portion of the plate, but also maintains the wettability of the plate.

What is the role of the printing plate?

The function of the printing plate is as follows: (1) After the surface of the printing plate is dried, the surface of the printing plate is covered with a hardened film to isolate the printing plate from the air, thereby preventing the oxidation of the printing plate. purpose. (2) The plate protective glue contains arabic acid. This acid is a very good cleaning agent for the greasy surface. The surface of the adhesive is more effective after drying. (3) After the surface is wiped with the protective glue, the glue contacts the inorganic salt layer of the plate to form a better hydrophilic film layer, which improves the hydrophilicity of the plate.

What protection does the plate have to do?

Due to physical and chemical constraints, as well as process conditions and process operations, a series of protective measures should be taken to maintain the normal printing of the plate and extend its useful life. In daily printing production, plate protection can generally be divided into static protection and dynamic protection. The protection that the plate is placed on or under the machine and is in a static state without work is called static protection. The measure of protecting the printing plate during the operation of the printing plate on the machine, which eliminates or reduces the interference of external factors, is called dynamic protection.