Platemaking process "skill repair"

In the process of printing PS plates in the printing industry, printing personnel often encounter such problems: due to the requirements of the CICPA, or the needs of the printing process, use the original wafers to make four-plate printing, or use The original joint edition was used to print six plates (or four plates) of eight plates (or six plates). The original film must not be damaged (especially in book covers and cover plates). What should I do if I encounter such a problem? The commonly used method is to dry out the printing plate according to the conventional method, and after the development is completed, the excess graphic image is repaired with a correction paste (or an amendment solution). However, due to the fact that some printing plates are joint plates, especially in the case of full-field or full-text version, it is often the case that when the plate is amended with a revised paste (or repair solution), the useful parts are eroded by potion. Affect the quality of the printing plate, and when it is serious, it can easily cause waste. If the useless part can't be repaired or not completely repaired, it will bring certain difficulties to the printing process. For example, when the printing occurs, the dirty version at the tip of the printing product will appear, resulting in phenomena such as printing plate stacking, rubber piled ink, and so on. The quality of the printed product.
In light of the practical difficulties that exist in our daily work, we "researched" a "skillless revision" method.
1. According to the requirements of the committee or the printing process, the first exposure of the printing plate shall be carried out according to the specified dimensions (forklifts and rules). This operation must be strictly standardized according to the printing operation.
2. At the same time as the second exposure of the printing plate, we will cut the red film of the film to the required size. The area of ​​the cut red film should be slightly larger than the area of ​​the required part of the printing plate, and one side must be trimmed. A straight line with no red film burr. Pay attention to check whether the red film used has a light leakage point, and if it can not be used.
3. When the first exposure is completed, remove the original film, cover the desired part of the printing plate (useful parts) with the prepared red film, and align the red edge of the film with the rules on the plate (if the original film No rules, you need to design the rules according to the size requirements before the first exposure, and stick them on both sides with adhesive tape (to prevent the red film from moving on the plate) and then put it into the printing machine. Vacuum exposure, before the exposure must pay attention to the turbulence of the red film and whether it leaves a "white edge." The exposure time at this time may be 1 to 2 times the first exposure time.
4. After the second exposure is completed, the normal plate-making process is performed again to obtain a conforming printing plate.