What is the quality of the reproduction of the PS version

PS version dot reproduction refers to the process of transferring the film dots to the PS plate through exposure and development during the printing process. The reproduction of outlets determines the quality of printed products. The reproducibility of the outlets is good, and the high quality and richness of the printed products are reflected.

1. Control of exposure

Excessive exposure will cause the dot to shrink, but instead it will enlarge the dot. The control of the exposure during operation is mainly carried out using dot control rulers and other control strips, and can also be determined by observing the color change of the photosensitive layer of the layout. Due to the green film consisting of basic brilliant blue BO and yellow sensitizer in the photosensitive liquid, as the exposure time lengthens, the diazo group in the photoreactive part decomposes. The yellow color gradually fades, showing a blue color. The blue part of the visible light part indicates whether the exposure is sufficient. Use it as a basis for drying, so as to obtain the ideal exposure.

2. Control of developer

The developer concentration should be based on the alkali resistance of the PS plate. Taking the test strip as an example, if 95% of the hollow dots after development are clear, 5% of the black dots are not lost, indicating that the development density is appropriate. The development temperature is generally controlled at about 25°C, and the development time is controlled at about 2 minutes.

3. Control of device operation

It should also pay attention to whether the printing equipment is under-inhaled, whether the light source illumination is uniform, and whether the printing lamp is aging or not. According to the actual situation of maintenance, the use of extended exposure time to compensate for the lack of exposure caused by the aging of the printing lamp.

4. Control of baking plates

In the baking version, because the temperature is too high, the PS plate will be softened, and the dot distortion will occur. Therefore, when printing high-grade printing products, the baking version is not recommended but the printed PS plate should be directly printed on the machine.

5. Management of film

It is also necessary to pay attention to the storage of the film and the storage of the PS plate before use, keep the work environment clean and dust-free, and at the same time standardize and digitize the exposure, development, baking and other technical operations, so that the temperature and humidity of the workshop are relatively stable.