Top 10 Corona Machine Brand & Manufacturers

What is a Corona Machine?

A corona machine, also known as a corona treater or corona discharge machine, is a device used to modify the surface properties of materials. It generates a corona discharge, which is a plasma-like state of ionized gas around a conductor. This discharge is used to treat the surface of materials such as plastics, films, papers, and metals to improve their wettability, adhesion, and printability.

History of Corona Machine

The development of corona machines can be traced back to the mid - 20th century when the need to improve the surface characteristics of non - conductive materials became more prominent. As the plastics industry grew and new types of polymers were developed, it was found that these materials often had poor adhesion and printability. The concept of corona treatment emerged as a solution. Early corona machines were relatively simple in design and had limited capabilities. Over the years, with advancements in electrical engineering, plasma physics, and materials science, corona machines have become more sophisticated, allowing for more precise control of the treatment process and the ability to handle a wider range of materials and applications.

Purpose of Corona Machine

• Printing and Packaging Industry: In the printing and packaging industry, corona machines are used to treat the surface of plastic films, papers, and cardboard. This treatment improves the ink adhesion, allowing for high - quality printing. For example, in the production of food packaging, the surface of the packaging material is treated to ensure that the labels and product information are printed clearly and do not peel off easily.
• Adhesive Bonding: When bonding different materials together, such as laminating plastic films to papers or attaching labels to plastic containers, corona treatment enhances the adhesive properties of the surfaces. It creates a more receptive surface for the adhesive, resulting in a stronger and more durable bond.
• Extrusion and Coating Processes: In extrusion processes, corona treatment can be applied to the surface of the extruded material to improve its compatibility with subsequent coating materials. For example, in the production of plastic sheets that will be coated with a protective layer, corona treatment helps the coating to adhere better, improving the overall quality of the product.

Principle of Corona Machine

Corona machines work based on the principle of corona discharge. A high - voltage, high - frequency electrical field is created between two electrodes, usually a metal electrode and a dielectric - covered electrode. The material to be treated passes between these electrodes. When the voltage reaches a certain level, the air or gas in the gap between the electrodes ionizes, creating a corona discharge. The ions and electrons in the discharge interact with the surface of the material, breaking molecular bonds and creating free radicals. These free radicals then react with the surrounding air or with other chemicals introduced in the process, resulting in a modified surface with improved wettability and adhesion properties.

Features of Corona Machine

• Surface Modification: Corona machines are highly effective in modifying the surface properties of materials. They can significantly increase the surface energy of materials, making them more receptive to inks, adhesives, and coatings. The degree of surface modification can be controlled by adjusting the power, speed of the material, and the distance between the electrodes.
• Versatility: These machines can handle a wide range of materials, including various plastics (such as polyethylene, polypropylene, and PVC), papers, films, and metals. Different materials may require different treatment parameters, but the corona machine can be adjusted accordingly to achieve the desired results.
• Non - Contact Treatment: Corona treatment is a non - contact process, which means that the material is not physically damaged or contaminated during the treatment. This is especially important for delicate materials or those that require a high - quality surface finish.
• Speed and Efficiency: Modern corona machines are designed for high - speed operation. They can treat materials at a relatively fast pace, making them suitable for industrial - scale production. The treatment time is usually very short, and the process can be integrated into existing production lines to increase productivity.

Types of Corona Machine

• Stationary Corona Machine: In a stationary corona machine, the electrodes are fixed, and the material to be treated passes through the corona discharge area. This type of machine is suitable for treating materials with a consistent width and thickness. It is often used in continuous - production processes, such as in the printing and coating of long rolls of material.[!--empirenews.page--]
• Hand - Held Corona Machine: Hand - held corona machines are portable and are used for treating small - area surfaces or for spot - treatment. They are useful for applications where a large - scale corona treatment machine is not practical, such as in the repair or customization of small - scale products or for treating hard - to - reach areas.
• Rotary Corona Machine: Rotary corona machines have a rotating electrode system. The rotation of the electrodes can provide more uniform treatment, especially for materials with uneven surfaces or for applications where a more consistent treatment across the entire surface is required. These machines are often used in the treatment of cylindrical or curved objects, such as plastic bottles or tubes.

Precautions for using Corona Machine

• Electrical Safety: Corona machines operate at high voltages, so it's crucial to ensure that all electrical connections are properly insulated and grounded. Operators should be trained in electrical safety and wear appropriate protective equipment, such as insulated gloves and safety glasses. Any electrical faults or malfunctions should be addressed immediately by a qualified electrician.
• Material Compatibility: Check the compatibility of the material to be treated with the corona treatment process. Some materials may be sensitive to the high - voltage discharge or may require specific treatment conditions. It's important to test the treatment on a small sample of the material first to ensure that it does not cause any damage or undesirable changes to the material's properties.
• Ventilation and Gas Emissions: The corona discharge process can produce ozone and other gases. Adequate ventilation is necessary to prevent the accumulation of these gases in the work area. Ozone is a harmful gas, and exposure to high levels can cause respiratory problems and other health issues. Some corona machines are equipped with built - in ventilation systems or gas - scrubbing units to reduce emissions.

Things to consider when purchasing Corona Machine

• Material and Application Requirements: Consider the types of materials you need to treat and the specific application requirements. For example, if you are mainly treating plastic films for printing, you may need a machine with a high - speed, continuous - treatment capability. If you are working with a variety of materials or need to do spot - treatment, a more versatile hand - held or rotary corona machine might be more suitable.
• Treatment Intensity and Control: Look for a corona machine that allows you to control the treatment intensity. The ability to adjust the power, treatment speed, and electrode distance is important for achieving the desired surface modification. Some machines come with advanced control systems and sensors to monitor and adjust the treatment process in real - time.
• Size and Integration: Consider the size of the corona machine and how it will fit into your production process. If you have limited space, a compact, modular - designed machine may be preferable. Also, think about whether the machine can be easily integrated into your existing production line, such as its compatibility with the material - handling systems and the speed of your production process.
• Cost and Long - Term Viability: Evaluate the initial cost of the corona machine, as well as its operating costs, including energy consumption, electrode replacement, and maintenance. Consider the expected lifespan of the machine and its potential for upgrades or expansion. A more expensive machine with better performance and durability may be a more cost - effective option in the long run.

Terms of Corona Machine

• Corona Discharge: The electrical discharge that occurs around a conductor when the voltage is high enough to ionize the surrounding air or gas. It is the fundamental process by which the corona machine modifies the surface of materials.
• Surface Energy: A measure of the energy of a material's surface that affects its wettability and adhesion properties. Corona treatment increases the surface energy of materials, making them more suitable for processes such as printing and bonding.
• Electrode: The conductive components in a corona machine that create the electrical field for the corona discharge. The design and configuration of the electrodes can affect the treatment efficiency and uniformity.
• Free Radicals: Highly reactive molecules or atoms that are formed during the corona discharge process. These free radicals play a crucial role in the surface - modification process by reacting with the material's surface and the surrounding environment to improve its properties.