Hi guys, this is Grace. I’m the sales director at China Rainbow Screen Printing Supply Ltd. Our company is a leading China manufacturer of screen printing inks. Today, I’d like to introduce the benefits of using screen printing ink on PET film. As we know, PET film is a plastic film material with medium and low surface energy, which necessitates surface pretreatment before printing to enhance its surface energy or wetting ability. If this step is skipped, the ink for PET products may not adhere properly, leading to easy peeling or falling off.
How can we achieve effective pretreatment?
A. Corona treatment: This method increases the surface energy through high-voltage discharge. There are two approaches: pre-processing by the supplier during material production and online processing on the printing press. The treated film should have a surface tension above 38 dyn. However, it’s important to note that not all PET materials can achieve a higher surface tension regardless of the current used in the corona treatment, leading to inconsistent results that can affect screen printing ink performance.
B. Surface coating: This involves applying an ink-friendly coating on the PET film surface, such as a corona-free PET film surface treatment agent, which improves its wetting ability for ink and enhances the ink’s adhesion. This method is the most ideal, common, and stable approach for PET materials.
After pretreatment, ensure the following before printing:
a. The material surface must be pretreated and meet required standards.
b. Use the appropriate special ink for PET products and conduct preliminary tests based on the actual production process.
c. Control the thickness of the ink layer and ensure it dries thoroughly to avoid issues with overprinted areas.
PET material boasts excellent physical properties and chemical resistance, making it suitable for various products, including bottles, membrane switch surface stickers, IMD panels, and self-adhesive labels. Our company has developed a series of screen printing inks specifically for PET materials, including both solvent-based and UV-based options, tailored for different PET product applications. We can show you some printed samples here for your reference.
