1, do the preparatory work before printing
The quality of PS plate is the basis for ensuring the quality of printing and printing, so before printing, it is necessary to carry out a comprehensive and careful inspection of PS plate to ensure that the surface of PS plate is smooth and smooth, and there is no dirt, scratches, etc. In addition, the temperature and humidity of the storage environment should be appropriate, avoid direct exposure to the air, and the storage time should not be too long.
In addition, the printing machine must be kept clean, the transparent glass plate is clean (usually wiped with alcohol), and the printing film is free of dirty spots.
2, reasonable adjustment of exposure
The most important work in the exposure link is the adjustment of the exposure amount, in the case of a certain intensity, you can adjust the exposure amount by changing the exposure time, the specific method is as follows.
First of all, a small piece with a side length of 100mm from the PS plate is taken as the test material, and then a blank sulphate paper is spread on it. After the exposure test is over, the sulphate paper is taken off and there is no trace on the surface of the PS plate. At this time, the determination of the standard exposure time is divided into the following two situations.
(1) If there are traces on the surface of the PS plate, the exposure time is extended by 10 seconds before the exposure test is done, and this is repeated until there are no traces on the surface of the PS plate, and the exposure time at this time is recorded as T1. Then, shorten T1 by 5 seconds (recorded as T2) and perform the exposure test again. If there is still no trace on the surface of the PS plate, T2 is used as the standard time, otherwise, T1 is used as the standard time.
(2) If there is no trace on the surface of the PS plate, shorten the exposure time by 10 seconds and then do the exposure test, and repeat until the traces appear on the surface of the PS plate, and record the exposure time at this time as T3. Then, the T3 is extended for 5 seconds (recorded as T4) before the exposure test, if there is no trace on the surface of the PS plate, T4 is used as the standard time, otherwise T3 is used as the standard time.
Under normal circumstances, if the PS version used is the same, the exposure time is fixed.
3, ensure good development effect
The concentration of developing solution, developing temperature and developing time are the main factors that affect the developing effect. The higher the developer concentration, the higher the development temperature, the longer the development time, the more full the reaction between the photosensitive resin and the developer on the PS plate surface, the more thorough the dissolution of the exposure site, but at the same time, it will cause dot shrinkage, or even loss of small dots; On the contrary, the reaction of the photosensitive resin and the developer on the surface of the PS plate will be slower, resulting in the degree of dissolution of the exposure part is not complete, which is easy to cause the commonly referred to "bottom gray too heavy" phenomenon, and the darkening part is easy to paste the plate.
The developer is best to choose the type provided by the PS version manufacturer. If the development powder is used, it must be formulated in strict accordance with the concentration standard of the developer, and pay attention to fully stirring to dissolve it evenly. In addition, because in the process of printing, the developer will continue to consume and volatilize, so it is necessary to supplement the developer according to the size of the workload.
In addition to the above three factors, it is also necessary to pay attention to the impact of the working environment and the performance of the stamping machine on the development effect.
4, carefully repair PS version
After the development work is completed, the graphics and blank parts of the PS version should be carefully checked, and the areas with dirty points should be repaired in time. During the printing process, the edge of the film will leave marks on the surface of the PS plate, so these marks should also be repaired. The repair tool is generally a retouching pen, and the use of the retouching pen should avoid moving above the graphic part as far as possible to avoid the retouching paste falling into the graphic part, affecting the quality of the graphic. After the PS plate repair is completed, it is necessary to quickly rinse off the retouching paste with water, and the rinsing method is used from inside to outside, so that the retouching paste is flushed to the graphic part.
5, take protective measures for the printed plate
In order to protect the printed plate, a layer of hydrophilic protective adhesive can be coated on the surface of the plate to prevent the blank part from being oxidized. When applying glue, try to make the glue liquid coated thin and thick evenly, and avoid hard objects scratching the plate layout. At the same time, pay attention to keep the printed plate in a clean place away from light.
6, check the plate quality
First, use a magnifying glass to check the reality of the dot. If the dot is round and full, 2% of the small dot is visible, 3% of the dot is clear, the intermediate dot is increased significantly, and the dark tone does not appear paste, then the plate quality is determined to meet the standard.

Then, check whether the graphic position of the plate surface, the position of the mouth and the drag tip are accurate, whether there is a crease in the plate layout, and whether the graphic is complete. Troubleshoot abnormal areas in a timely manner.