DOMADIA™ Polyimide Corona Treated Films

What Are DOMADIA™ Polyimide Corona Treated Films?

DOMADIA™ CORONA TREATED POLYIMIDE FILMS or DOMADIA™ KSV POLYMIDE FILMS are high-performance plastic films made from polyimide resin, which are then treated using corona discharge to modify their surface properties. Polyimide itself is known for its exceptional thermal stability, chemical resistance, mechanical strength, and electrical insulating properties. These are often Single Side treated. Seldome double side treated is used.

The corona treatment is applied to improve the film’s surface energy, thereby enhancing adhesion for printing, coating, or lamination applications.

Manufacturing Process Overview

1. Base Film Production

The base material is a polyimide film, typically manufactured through polycondensation of aromatic dianhydrides and diamines, cast and then imidized at high temperatures (~300°C or more). Common trade names include Kapton®, Apical® – are not our brands!

2. Corona Treatment

Corona treatment is a non-contact surface modification technique that involves exposing the film surface to a high-frequency, high-voltage electrical discharge in the presence of air. This creates a plasma field above the film surface.

What Happens During Corona Treatment:

• High-energy ions and ozone in the plasma interact with the surface.
• They break molecular bonds on the surface of the film.
• Polar groups (like –OH, –COOH) are introduced.
• This increases the surface energy (typically measured in dynes/cm), improving wettability and adhesion.

Key Properties and Advantages

Applications Polyimide Corona Treated Films

Polyimide corona treated films are used across high-tech, electrical, and industrial sectors where extreme reliability is needed:

1. Electronics and Electrical Applications

Flexible Printed Circuits (FPCs)

Used as a base film for copper circuitry. Corona treatment improves adhesion between polyimide and metal foils, essential for durability in foldable and compact electronics.

Wire and Cable Insulation

Acts as heat- and voltage-resistant wrapping. The treated surface ensures strong bonding with adhesives or coatings.

Capacitor and Transformer Insulation

Functions as dielectric or interlayer insulation. Surface treatment ensures uniform coating and adhesion of dielectric materials or epoxy varnishes.

2. Industrial and Mechanical Uses

Adhesive Release Liners

Polyimide films serve as carriers for pressure-sensitive adhesives. Corona treatment allows precise control over adhesion or release, depending on the requirement.

High-Temperature Masking

Used during coating, etching, or soldering. Corona-treated surfaces hold masking layers securely, even under heat or chemical exposure.

Surface Protection Films

Applied to sensitive surfaces during manufacturing. The treatment allows better bonding of temporary protective coatings or labels.

3. Aerospace and Defense Applications

Thermal Insulation Blankets

Used in spacecraft and satellites. Corona treatment enables lamination with reflective or anti-static layers.

Sensor and Wiring Protection

Encapsulates sensors and wiring in avionics. Treated surface improves bonding with potting compounds or protective films.

4. Medical and Wearable Devices

Flexible Biosensors

Polyimide films form the substrate for on-skin electronics like ECG patches. Surface treatment enables bonding with skin adhesives or biocompatible inks.

Microfluidic and Lab Devices

Used in diagnostic tools requiring controlled fluid movement. Corona treatment introduces hydrophilicity for better fluid control.

5. Printing and Specialty Packaging

 High-Temperature Labels

Used in solder-resistant or sterilization-safe labels. Treated surface supports ink and adhesive retention at high temperatures.

Printable Film Substrates

Serves in industrial or technical labeling. Corona treatment allows printing with standard UV or thermal transfer methods.

Common Variants

Some polyimide films may be dual-sided corona treated, or corona treated on one side and coated (e.g., with a primer or adhesive) on the other. Others may be laminated with metal foils (like copper or aluminium) for advanced applications such as thermal management or shielding.

Why Use Corona-Treated Over Untreated?

Surface Testing

Treated films are usually tested using:

• Dyne test pens or solutions (to check surface energy)
• Peel strength tests (for adhesive bonding)
• Contact angle measurements (lower angle = better wetting)

Conclusion

Polyimide corona treated films are engineered surfaces combining the high-performance capabilities of polyimide with enhanced surface activity for coatings, laminations, and printing. They are essential in high-reliability industries where conventional polymers would fail, particularly where adhesion and precision are critical.

Related Product

Polyimide Films