1. Prepare the Surface
Pre-treatment: Silicone is a low-energy surface, meaning it doesn't naturally hold ink well. Surface treatments like flame treatment, plasma treatment, or corona treatment increase adhesion by creating a receptive layer for the ink. This step is crucial for good bonding.
2. Mix the Silicone Ink
Silicone inks are typically two-component (2K) systems, including silicone ink base and a catalyst or curing agent.
Measure and mix according to the manufacturer's instructions, ensuring the right ratio of ink to catalyst. Improper mixing can impact adhesion and curing.
Pot life: Once mixed, the ink has a limited working time. Apply promptly, as it will begin curing after mixing.
3. Set Up the Screen
Choose a mesh count appropriate for silicone inks, typically in the 150-200 mesh range. The screen should allow for enough ink deposit but maintain detail.
Emulsions resistant to silicone inks and solvents are recommended to ensure durability over multiple prints.
4. Apply the Ink
Printing: Using a squeegee, apply the ink evenly across the screen, ensuring a smooth, even layer on the substrate.
Flash Curing (Optional): Depending on the application, a flash cure between layers can be used to set the ink and prevent smudging if multiple layers or colors are being applied.
5. Cure the Ink
Silicone ink requires heat curing to set and fully bond with the substrate. Cure in a dryer or heat press at temperatures of 250-300°F (121-149°C) for 2-5 minutes, depending on the ink manufacturer's specifications.
Proper curing is essential for durability and flexibility, allowing the print to withstand washing, stretching, and outdoor conditions.
6. Final Checks
Once cured, inspect the print for adhesion, flexibility, and clarity. Silicone prints should feel smooth and be able to stretch with the substrate without cracking or peeling.
Tips for Best Results
Use ventilation in the workspace due to fumes generated during curing.
Test ink adhesion and durability on a sample piece before full production, especially if working with new substrates or ink brands.
Silicone screen printing inks are ideal for applications on silicone rubber items, sportswear, and other flexible or high-stretch materials, providing a high-quality, long-lasting print.