Printing plate development is difficult.
Causes:
(1) too long exposure time.
(2) after scraping, stored for a long time.
(3) excessive drying temperature causes thermal crosslinking.
(4) the photosensitive adhesive has been exposed.
(5) when the bottom plate and film contact is not solid.
(6) failure of photosensitive adhesive.
(7) diffraction of light during exposure.
Solutions:
(1) conduct exposure test and adjust the exposure time.
(2) shorten the storage time.
(3) control the drying temperature according to the instructions.
(4) check operating room lights.
(5) close contact between film and photosensitive film by vacuum adsorption or other means.
(6) replace with new photosensitive adhesive.
(7) use of colored screen.
Basement membrane residues
Causes:
(1) the preparation and use time of photosensitive emulsion is too long.
(2) uneven coating.
(3) excessive drying temperature causes thermal crosslinking.
(4) improper selection of exposure lamp source.
(5) underexposure or overexposure.
(6) when the bottom plate and film contact is not solid.
(7) when the bottom plate and film contact is not solid.The background itself small black and white contrast.
(8) insufficient development time.
(9) the time, method and strength of the version is not correct.
Solutions:
(1) shorten the use interval.
(2) increase the screen tension, with the net pulp evenly on the glue.
(3) control the drying temperature according to the instructions of photosensitive adhesive.
(4) reasonably select lamp source, with strong ultraviolet light (halogen lamp) as the appropriate.
(5) conduct exposure test and adjust the exposure time.
(6) use vacuum adsorption or other methods to make it close joint.
(7) check the transparency and blackness of the bottom plate.
(8) increase the development time to show the text.
(9) correct control of printing time, method and strength, please refer to the relevant chapters of this manual.
The screen has pinholes
Causes:
(1) bad screen degreasing dirty.
(2) the bottom plate is not clean, there is dirt on the print plate.
(3) too fast gluing speed.
(4) there are bubbles or dirt in the emulsion.
(5) there is water on the screen fiber, poor drying.
(6) insufficient sizing scraping.
(7) failure of photosensitive adhesive.
Solutions:
(1) clean the screen with good quality cleaning agent.
(2)remove dust and dirt from the picture and vacuum frame.
(3) slow and uniform coating.
(4) stir and let stand for some time.
(5) under the specified temperature, thoroughly dry screen.
(6) increase the number of squeegee (2-3 times)
(7) replace with new photosensitive adhesive
Photographic film and screen bond is not good.
Causes:
(1) bad screen degreasing dirty.
(2) insufficient drying time.
(3) improper flushing.
(4) underexposure, should not be dissolved in the development of the part to ease the decomposition.
(5) uneven coating.
(6) uneven mixing of colloids and photosensitive agents, emulsion placement time is too long.
Solution:
(1) clean the screen with good quality cleaning agent.
(2) thoroughly dry the wire mesh at the specified temperature.
(3) check the washing temperature according to the instructions of photosensitive adhesive.
(4) increase exposure time and conduct exposure test.
(5) increase the screen tension, with the net pulp evenly glue.
(6) stir and mix evenly, check its ratio, and check the storage period stipulated by the manufacturer.
The photosensitive film is used for a short time or the screen is damaged.
Causes:
(1) screen degreasing dirty, dry is not complete.
(2) deformation of wooden mesh frame.
(3) mesh tension relaxation photosensitive film surface produced unbalanced contraction.
(4) the drying temperature is too high to produce deformation screen.
(5) insufficient film thickness.
(6) ink fineness is not enough or there is a foreign body.
(7) mechanical friction.
(8) improper solvent, and photosensitive adhesive reaction.
(9) underexposure.
(10) poor ink quality, on the screen drying fast, wash too much.
(11) excessive scraping pressure during printing.
Solutions:
(1) use good quality cleaning agent to clean the screen and dry in a clean place to prevent secondary pollution.
(2) replace with aluminum mesh frame.
(3) increase the tension of the tension net, and put a period of time to get online version of the glue, the tension net to be placed for 2-3 days before printing.
(4) use a thermostat to keep the temperature below 40℃ (or see instructions for use of photosensitive paste).
(5) uniform coating, increase the thickness of the adhesive layer.
(6) continue to grind ink and remove foreign matter after filtration.
(7) when washing the plate, the application of soft articles to scrub
(8) pay attention to the use of solvent and photosensitive adhesive match.
(9) conduct exposure test, increase exposure time and conduct secondary exposure.
(10) improve the quality of ink, avoid drying too fast, reduce the number of wiping.
(11) reduce the scraping pressure and repair the blade of the scraper.