Corona Treatment Considerations for Your Company

Published: April 04, 2022

A question-and-answer with Alyxandria Klein, Marketing and Sales Director, QC Electronics.

What are critical steps to guaranteeing adhesion in your process?

Klein: Guaranteed adhesion requires precise control of the material’s surface energy.
In order to control the surface energy, understanding watt density and the application of corona discharge is crucial. Companies understand their process and bonding application but are often unaware of the importance of the actual composition of the surface of their material. This is where problems become prevalent.

When bonding, companies must understand their coating type, process of application, and the characteristics/composition of the surface the bonding is occurring to in order to have a guaranteed successful process.

What are factors that affect treatment that should be observed and understood?

Klein:

1. Knowledge of the adherent’s bonding characteristics
2. Knowledge of the adherend’s surface characteristics for bonding
3. Understanding of required dyne level/surface energy for your application
4. Environment/travel of product
5. Storage
6. Contaminants/Handling

How can companies improve their converting processes?

Klein: Corona should be applied directly before bonding, with as little time between treatment and bonding as possible. The increased surface energy caused by application of corona decays over time at different rates depending on your material – this is another reason understanding your material is so important. The degradation rate should be understood when deciding where the corona treater will be placed on your line. If you are sheet treating, you should make sure the treated sheets are adhered to as soon as possible. This relates to any application.

Dyne levels are great for printing applications, but more complex applications require more accurate readings of surface energy to be able to guarantee bonding. Contact angle measurement is a great way to get those accurate readings to fully understand your adherent and adherend’s bonding capabilities. KRUSS’s mobile surface analyzer is a great tool for measuring contact angle.

Following a maintenance schedule also ensures your corona treater is running at top performance. This includes checking in on the equipment’s components and cleaning and lubricating when necessary.

What problems are associated with inconsistent or improper surface treatment?

Klein: Faulty corona treatment is obvious when looking at your end-product. The results will be visible in inconsistency of your adherent throughout the surface of material, or not adhere at all if required surface energy is not understood and applied. Incorrect corona treatment is a leading cause of delamination and product failure.

If the entire surface is not treated properly and evenly, the surface energy of the substrate will vary from point to point on the material. This causes the adherent to adhere where it is treated, and separate where it is not to a sufficient surface energy for adhering. The surface energy of the substrate must be higher than the surface energy of the adherent in order for a bond to occur. The areas where the surface energy is not will fail.

What are key factors converters should pay attention to when choosing the best solutions and manufacturer or supplier?

Klein:

• Reliability
  • Quality
  • Simplicity of operation/maintenance
  • Consumables/rate of replacement
  • Control of corona (High definition)
  • Type of programming utilized
  • Send samples to ensure success with your potential treater supplier
  • Required maintenance schedule

When purchasing a corona treater, it is an accessory to your line. The corona treater is like oil in a car: a vital element, but a small component in the scheme of things. The oil should be easy to change when necessary and perform to run the engine at its best. When purchasing a corona treater, you want to make sure that it is going to perform as that vital element to allow the process to run as predicted. Oil in a car is often forgotten about. That’s what you should be able to do with your corona treater – be confident that it will always perform its job and enjoy the fruits of your successful production line.

Learn more at This email address is being protected from spambots. You need JavaScript enabled to view it. or www.qcelectronics.com.