ABC's of Corona Treating

What is Corona Treatment?

Corona treatment is a surface modification process used to enhance the adhesion properties of materials, especially non-porous plastic substrates such as polypropylene and polyethylene.  This process involves using a high-frequency or low frequency electrical discharge, known as a corona, to alter the surface energy of a material. By increasing surface energy, corona treatment enables better bonding of inks, coatings, adhesives, and other substances, making it an essential pre-treatment technique in the printing, packaging, and manufacturing industries.

Corona treatment is defined as a high-voltage electrical discharge, often visible as a blue arc. This process is applied directly to the surface of materials with inherently low surface tension. By pre-treating these materials with corona, their surface tension is increased, significantly enhancing their ink adhesion and wettability. This improvement is critical for achieving consistent and durable results in printing, coating, and bonding applications.

Why is Corona Treatment Important in Printing?

In printing industries, achieving strong adhesion between inks or coatings and the substrate is critical for durable, high-quality results. Many materials, particularly plastics, have low surface energy, which naturally resists adhesion. Without proper treatment, the ink or coating may peel, chip, or fail to adhere uniformly.

Corona treatment solves this problem by:

1. Increasing Surface Energy: It makes the material more receptive to inks, coatings, or adhesives.
2. Improving Print Durability: Treated surfaces result in prints that resist wear and maintain quality over time.
3. Enhancing Ink Coverage: It ensures uniform application of inks, reducing the risk of smudges or inconsistencies.
4. Broad Compatibility: Works with various printing technologies, including pad printing, screen printing, and digital printing.

How Does Corona Treatment Work?

The corona treating process involves three key steps:

1. Electrical Discharge: A high-frequency electrical current generates a corona, which is applied to the surface of the substrate.
2. Surface Modification: The corona oxidizes the surface, increasing its energy and improving its wettability.
3. Enhanced Bonding: The treated surface becomes more adhesive-friendly, allowing inks and coatings to adhere firmly.

Applications of Corona Treatment in Printing Industries

Corona treatment is widely used across various sectors, including:

• Packaging: Printing on flexible films, such as polyethylene and polypropylene.
• Consumer Goods: Decorating plastic products, from electronics to toys.
• Automotive Components: Ensuring durable markings on plastic and composite parts.
• Medical Devices: Enhancing adhesion for sterilized equipment and tools.
• Glass and Metal: Applying coatings or prints on non-porous materials.
• Injection Molded Plastics: Such as Polyethylene, Polypropylene, and other plastics with low surface tension.
  

What is the Target Dyne Range for Polyethylene (PE) and Polypropylene (PP)?

Dyne Levels for Excellent Ink Adhesion

• Polypropylene (PP):
  Target a surface energy of 38-42 dynes/cm.
  • At this level, the surface is sufficiently modified to ensure good adhesion of inks and coatings.
• Polyethylene (PE):
  Target a surface energy of 38-40 dynes/cm.
  • PE has a naturally low surface energy (~31 dynes/cm), so corona, flame, or plasma treatment is needed to raise it to the desired range.

Benefits of Corona Treatment for Printing Industries

1. Cost-Effective: Eliminates the need for specialized substrates, allowing the use of standard materials.
2. Environmentally Friendly: Reduces the need for chemical primers or adhesives.
3. Versatile: Compatible with a wide range of materials and printing methods.
4. Boosts Production Efficiency: Improves bonding performance, reducing rejects and rework.

Why Choose Deco Tech for Corona Treatment Solutions?

At Deco Technology Group, we understand the critical role corona treating plays in achieving superior printing results. Our industry-leading expertise ensures that your business benefits from high-quality equipment and technical support tailored to your needs. Whether you're printing on plastics, metals, or glass, we provide the solutions to optimize adhesion and enhance your production process.

Learn More About Corona Treatment

Ready to explore how corona treatment can revolutionize your printing operations? Contact Deco Technology Group at (714) 639-DECO or visit our website to learn more about our surface treatment solutions and how they can improve your printing results.