Offset printing plate technical question and answer

1. What is the difference between a UV plate and an ordinary plate or CTP plate?
UV ink adaptability classification of various printing plates Normal PS version UV ink PS version CTP Brand: VPS-A VPU LH-PI
Price: cheaper than UV PS version is more expensive than the ordinary PS version Your resistance to India: not ideal Well, because the actual sales price is determined by a sales agency, please contact the agency for details.
2. Is the printing plate easily dirty mainly due to several reasons?
(1) Reasons: Underexposure, poor transparency of the Yang picture, aging of the light source, processing methods: re-produce the Yang picture, moderately adjust the exposure time: re-test with the gray ladder ruler, extend the exposure time, or replace the light source lamp.
(2) Reason: The glass of the printing machine is a little dirty, and the adhesive residue is attached to the positive picture. Treatment method: Use glass cleaner and film cleaner to get dirty.
(3) Cause: During development, due to the adhesion of blisters, the development was poor, and the developing solution nozzle was bubbling due to clogging. Remedy: Eliminate blistering: Wash the developer nozzles.
(4) Reason: When using the PS version, hands are not clean (there are fingerprint smears). Treatment method: Keep mouth and slightly after the operation.
(5) Reason: The glue is thin. Treatment method: Increase glue concentration.
(6) Cause: The adhesive layer was peeled off (when the adhesive layer was not dry, the adhesive was overlapped and stored). Treatment method: Do not keep in high temperature and high humidity conditions.
(7) Reason: After the plate is finished, it is stored under high temperature and high humidity conditions. Treatment method: Do not store under high temperature and high humidity conditions.
(8) Cause: The concentration of the developer was too low and the development was incomplete. Treatment method: adjust the developer to standard concentration.
3. How to improve the development quality of positive PS version?
The dilution rate of the developer should be respected by the proportion specified by the PS manufacturer, and a small sample plate (using the Fujifilm gray scale to expose a small-sized PS plate after exposure, which can measure the developer concentration). The developer concentration is managed.
4. In the printing process, the phenomenon of dirt on the printing plate is often seen. How can this be solved?
(1) Reason: When the printing stops, the printing plate is not wiped and protected. Treatment method: wipe protective plastic.
(2) Reason: The blank part of the printing plate is not wet enough. Treatment method: Increase the amount of water appropriately.
(3) Cause: Emulsification of the viscera occurred. Treatment method: Adjust the balance between ink and fountain solution, or replace the ink and fountain solution.
5. Why is it that film collages are prone to deficiencies?
(1) Reason: Improper film collage is not proper. Treatment method: The film from the image part 3 mm above the collage.
(2) Cause: The developer concentration is too high. Treatment method: adjust the developer to standard concentration.