Exclusion of Screen Printing Failure on Plastic Products

Exclusion of screen printing failure of plastic products

Failure name

Causes and Countermeasures

Difficult to develop

(1) Excessive exposure time causes diffraction of light. The exposure time should be shortened appropriately.
(2) After the exposure was not developed in time, some photosensitive films spontaneously hardened after receiving light. It should be developed in time after exposure.
(3) The darkness of the bottom plate pattern is insufficient, causing light transmission. Should increase the darkness of the plate.
(4) At the time of exposure, the adhesion of the base plate to the photosensitive film was too poor. Vacuum suction should be used to make it close.
(5) baking temperature is too high or too long. The baking temperature and time should be adjusted properly.
(6) uneven thickness of photosensitive film. Should pay attention to smearing when scraping

Photosensitive film peels off

(1) The photosensitive film is too thick and the light hardening is not thorough. Pay attention to the thickness of the squeegee.
(2) Film drying is insufficient. The baking temperature and time should be adjusted properly.
(3) The screen surface treatment before scraping is not clean. Care should be taken to clean the screen before scraping.
(4) Insufficient exposure. Appropriately increase the exposure time.
(5) The development time is too long and the spray pressure is too high. Should shorten the development time and reduce the water pressure of the gun

Plate layout with pinholes

(1) There is dust on the bottom plate. Should pay attention to the purification of the working environment.
(2) The emulsion contains impurities. The emulsion should be filtered again.
(3) Bubbles in the film during squeegeeing. Care should be taken to avoid bubble formation.
(4) The surface cleanliness of the screen is too poor. Care should be taken to clean the surface of the screen before scraping

Unclear plate pattern

(1) The bottom plate does not meet the plate making requirements and its pattern is not clear. The trim should be trimmed or replaced.
(2) The exposure time is too long, the pattern becomes thin and imaginary. The exposure time should be appropriately shortened to control the exposure.
(3) The angle of the stretch net or the angle of the printing plate is not good, resulting in a zigzag pattern. Should be appropriate to adjust the stretching and the angle of the printing.
(4) The adhesion of the base plate to the photosensitive film is too poor at the time of exposure. Should pay attention to close contact

2. Troubleshooting of printing problems

Failure name

Causes and Countermeasures

Bad ink

(1) Improper ink selection. The ink should be replaced.
(2) The ink dries too quickly. Slow-drying inks should be used.
(3) The viscosity of the ink is too high. Slower than solvents should be used to lower the viscosity.
(4) Plate jams. The plate should be cleaned.
(5) Insufficient printing pressure. Should increase appropriately.
(6) poor surface treatment of the substrate. Should strengthen the preprint processing of substrates