Flame Plasma Treatment or Corona? How to Optimise Adhesion and Printability in Plastic Processing

In plastic manufacturing, effective surface treatment is essential to ensure strong adhesion, high-quality printing, and long-term durability. Two leading technologies—flame plasma treatment and corona treatment—achieve this by increasing the surface energy of plastic materials. However, their capabilities, performance, and limitations differ significantly.

Introduction to Surface Treatment for Plastics

Surface treatment modifies the surface of plastic parts to improve bonding with inks, adhesives, and coatings. Both flame plasma and corona are widely used in packaging, automotive, and converting industries, but choosing the right method depends on your production needs and quality requirements.

How Flame Plasma Treatment and Corona Work

Flame Plasma Treatment uses a highly controlled oxidising flame to create a reactive plasma that bombards the plastic surface. This process removes contaminants and chemically alters the surface, increasing surface energy and enabling strong, durable adhesion.

Corona Treatment applies high-voltage electrical discharge to ionise air around the plastic, creating reactive oxygen species that lightly oxidise the surface. While it raises surface energy, the effect is shallow and may degrade over time.

Comparing Adhesion, Printability, and Durability

Flame plasma treatment provides stronger, longer-lasting adhesion thanks to deeper chemical activation. This is essential in sectors like automotive and medical, where bonding reliability matters.

It also delivers better printability, with improved ink absorption and reduced delamination risk. Corona treatment can suffice for low-demand applications but often falls short in long-term performance and colour clarity.

Limitations of Corona: Width and Line Speed

Corona treatment is typically limited to narrow web widths, making it unsuitable for large-format plastic sheets or high-output processes. Flame plasma systems can be configured for treatment widths of up to 20 metres, supporting wide web processing and large parts.

Additionally, line speed is restricted with corona, as consistent exposure is required for effectiveness. Flame plasma operates efficiently at higher speeds, giving it a clear edge in fast-moving production lines.

Cost, Efficiency, and Environmental Impact

While flame plasma systems may have higher initial costs, they offer long-term benefits: reduced rework, longer treatment retention, and lower scrap rates.

Environmentally, flame plasma uses natural gas and produces minimal byproducts. Corona treatment can generate ozone as a byproduct, requiring appropriate ventilation or extraction systems.

Conclusion: Choosing the Right Surface Treatment

For manufacturers seeking scalable, high-performance surface activation, flame plasma offers significant advantages over corona. It delivers stronger adhesion, wider treatment widths, and faster processing—key factors in competitive industrial environments.

To learn more about how this technology can support your production goals, explore our Flame Plasma Surface Treatment solutions

You can also request a tailored technical proposal from our team today.