In the process of screen printing silicone printing, it is crucial to ensure accurate overprinting. Here are some key steps and precautions to ensure the accuracy of overprinting:
Choose the right silicone screen:
The choice of silicone screen should be determined according to the characteristics of the printing material and the printing requirements.
Consider factors such as the number of meshes, wire diameter, and screen tension of the screen to ensure that the printing effect reaches the expected goal.
Make the film accurately:
When making the film, ensure that the main color pattern is slightly larger than the actual printing demand to compensate for the ink layer thickness and covering power of screen printing.
Follow the principle of offset printing first and screen printing later, and try to optimize the arrangement of process colors to reduce color error.
Control printing pressure:
The control of printing pressure is crucial to the accuracy of overprinting.
Excessive pressure will cause excessive extrusion of ink, resulting in too thick ink layer or distorted ink dots; too little pressure will cause uneven ink layer of printed products.
Therefore, it is necessary to reasonably adjust the printing pressure to ensure that the ink can be evenly transferred to the printing material.
Choose the right ink:
Choose the right ink type according to the printing material and printing requirements.
Water-based ink is suitable for materials with strong water absorption, such as paper and cloth; solvent ink is suitable for non-absorbent materials, such as plastic and metal.
When choosing ink, factors such as printing speed and drying time should also be considered.
Adjust the printing speed:
Printing speed that is too fast may cause the ink to not be fully transferred to the printing material, affecting the printing quality.
Printing speed that is too slow will increase production costs and reduce production efficiency.
Therefore, it is necessary to reasonably control the printing speed according to the equipment performance and printing requirements of the silicone screen printer.
Keep the printing environment stable:
The temperature and humidity of the printing workshop have a great influence on the color registration accuracy.
The temperature and humidity in the workshop should be kept stable as much as possible. Generally, the temperature is controlled at 20℃-23℃, and the relative humidity is controlled at 40%-60%.
Regularly maintain and inspect equipment:
Regularly maintain and inspect the printing equipment to ensure that the equipment is in the best working condition.
Check the wear of components such as screens, scrapers, and ink delivery systems, and replace or adjust them in time.
Use a high-precision overprinting system:
If conditions permit, the use of a high-precision overprinting system can greatly improve the accuracy of overprinting.
These systems are usually equipped with advanced sensors and control systems that can monitor and adjust various parameters in the printing process in real time.
In summary, the overprint accuracy of screen printing silicone printing can be greatly improved by selecting the right silicone screen, accurately making the film, controlling the printing pressure, selecting the right ink, adjusting the printing speed, keeping the printing environment stable, regularly maintaining and inspecting the equipment, and using a high-precision overprint system.