Screen printing silicone is a common printing process, but some common problems may be encountered during actual operation. The following is a summary and analysis of these problems:
1. Insufficient ink adhesion
Reason:
The surface tension of silicone is too high.
Improper use of treatment agent, such as insufficient stirring, incorrect ratio or improper dilution ratio.
The surface of silicone is not cleaned, and there are oil stains or impurities.
Solution:
Ensure that the surface of silicone is clean and free of oil stains.
Select a screen printing treatment agent suitable for silicone material, and dilute the treatment agent according to the ratio provided by the manufacturer to ensure that the diluted treatment agent is stirred evenly.
Appropriately increase the printing pressure and extend the drying time.
2. Uneven printing
Reason:
Uneven ink concentration.
Poor quality of printing screen, such as screen wear, blockage or improper selection of mesh number.
Printing speed is too fast.
Solution:
Ensure the ink concentration is appropriate and check the mixing and stirring of ink regularly.
Use a good quality printing screen and clean the screen regularly to keep it clean and unobstructed.
Appropriately reduce the printing speed to ensure that the ink can be fully transferred to the silicone surface.
3. Characters are offset or blurred
Reason:
The jig or screen is not positioned accurately during printing.
The printing pressure is uneven or too large/too small.
The ink is displaced during drying.
Solution:
Adjust the positioning of the jig or screen to ensure accurate printing position.
Adjust the printing pressure to make it uniform and moderate.
Control the drying process of the ink to avoid displacement during drying.
4. Characters fall off
Reason:
The baking temperature and time are insufficient, resulting in incomplete curing of the ink.
The quality of the screen printing ink is poor and cannot meet the adhesion requirements of the silicone surface.
The surface of the silicone product is too dirty or the amount of release agent used is too high.
Solution:
Check the set temperature and wire speed of the baking tunnel furnace to ensure that the ink can be completely cured.
Use high-quality screen printing ink to ensure that the adhesion requirements of the silicone surface are met.
The amount of release agent used during molding should not be too high, and the silicone surface should be kept clean during subsequent processing and storage.
5. Screen sticking problem
Reason:
There are fine particles or ink on the screen.
Solution:
Use transparent glue or professional cleaning tools to clean impurities and ink on the screen.
In summary, there are many problems that may be encountered in the process of screen printing silicone, but as long as the correct solutions are mastered, these problems can be effectively avoided, thereby improving printing quality and efficiency.