Many secondary processes prior to decorating and bonding require strong adhesion to be successful. However, certain substrates have insufficient surface energy for creating the required bond strength. To bond these types of challenging materials, surface treatment such as plasma or corona treatment significantly improve adhesion. This article will discuss some of the most common bonding challenges and outline how surface treatment overcomes these difficulties.
What Is the Purpose of Surface Treatment?
Surface treatment is used to improve bonding or “functionalize” the surface of a substrate. This useful technology modifies the surface of a material in a way that allows for strong bonds to be formed between the substrate and a label, a coating, print, or adhesive. Surface treatment, such as atmospheric plasma (also called in air plasma) and corona treatment work by improving surface tension. Numerous bonding problems are successfully solved through surface treatment, even those involving elastomeric or polymeric materials.
There are significant costs associated with bonding failure, including poor product field performance, excess scrap and rework, production inefficiencies, and increased quality control. Surface treatment solves virtually any bonding challenge, even when using the most difficult-to-bond materials.
Corona and plasma surface treatment prepare materials for improved adhesion by:
Raising the material’s surface tension or wettability by altering the molecular properties of the surface
Improving the bond strength between the applied media and the material
Plasma treatment provides mechanical etching and micro-cleaning, as well as elevating surface tension
Bonding Items With More Than One Type of Material
Note how the ink on the left side of the corona treated polystyrene tray fully bonds with the material, but beads up on the non treated right side.
Materials that feature low surface energies, such as those between 20 and 40 dynes, are notoriously difficult to bond. In plastics, this includes materials such as polytetrafluoroethylene (PTFE), polypropylene, and polyethylene, polystyrene, among others. Composite materials are also challenging in bonding applications because the different materials they contain typically feature differing surface energies.
Achieving workable wettability of a substrate requires the surface energy of the substrate to exceed the surface tension of the media being applied. Using surface treatment to increase the substrate’s surface tension causes media to evenly flow and adhere to the material’s surfacefor highly improved bonding capabilities.
How to Activate the Surfaces of Difficult-to-Bond Materials
When activating the surface of challenging materials, the first consideration should be the surface energy of the substrate. The surface energy will determine whether or not media will successfully bond with the material. Wettability is another prerequisite of successful adhesion. The term wettability describes the ability a liquid has to maintain contact with a type of media. It is influenced by intermolecular interactions that are altered through corona and plasma surface treatments.
Atmospheric plasma is created by combining reactive gas molecules and an electric field. This system uses one or more high voltage electrodes, which charge the surrounding blown gas molecules, resulting in a highly ionized field that is forced onto the targeted surface. This ionized air stream reacts with the substrate and breaks the existing hydrogen bonds by introducing oxygen which recreates the chemical properties of the surface. This intensified reaction causes the material to wet out and accept media, as well as etches and micro-cleans the surface.
3DT’s plasma treatment is not confined to a chamber, but performed in fast, inline production lines. What’s more, plasma is environmentally friendly and potential-free, meaning it can be used on or near metal parts and wiring.
Corona treatment also improves a material’s surface tension to solve bonding problems. It is probably the most common and economical type of surface treatment. In contrast to plasma treatment, corona relies on two electrodes and an isolator to create a cloud of ionized air, corona discharge, that breaks molecular bonds on the surface of a material. Surface oxidation occurs, creating covalent bonds resulting in enhanced wettability and adhesion capabilities.
Custom PolyDyne Pro corona treatment system with indexing table for the treatment of labware flasks.
Surface Treatments for Powerful Adhesion from 3DT
Working with materials that are resistant to printing and bonding requires surface treatment processes that improve surface tension and eliminate bonding problems. 3DT manufactures a comprehensive line of surface treatment systems to improve bonding for numerous applications. Our solutions raise surface energy and improve bonding on even the most challenging substrates.
With over 30 years of specialized experience, 3DT provides the most innovative corona and plasma treatment systems. Our equipment addresses the needs of diverse industries and can be used as stand-alone stations or incorporated into a production line. We specialize in process development for demanding applications. Learn more by visiting our corona and plasma treatment process page, or get started on your solution by requesting a quote today.
3DT has manufactured corona and plasma treatment systems for over 30 years. Our solutions enhance the surface characteristics in materials and components, including adhesion, bond strength, cell culture growth, cleanliness, and wettability. We offer a broad range of standard and custom options in our PlasmaDyne Pro series for use in customer facilities that accommodate a wide number of applications and substrates. 3DT’s systems can be used for plasma treatment for plastics, glass, foam, metal, and more.
What You Should Know About Plasma Treated Surfaces eight interesting facts about plasma treatment that address why they are used, how they are used, and more.
#1 Plasma: The 4th state of matter.
Everyone is familiar with the three states of matter (solid, liquid, gas), but the fourth state is one that is less well known- plasma energy. Yet, everyone is familiar with lightning seen on a summer evening. This powerful energy is plasma! Essentially, plasma is an ionized gas consisting of approximately equal numbers of positively and negatively charged particles. There are two general forms of plasma: high-temperature plasmas that are found in stars and in fusion reactors; and low-temperature versions used in surface treatment, neon and fluorescent lighting, plasma TVs and semiconductor manufacturing.
#2 Plasma surface treatment is powerful enough to break hydrogen bonds.
Plasma surface treatment is created by combining reactive gas molecules and an electric field. This method uses one or more high voltage electrodes which charge the surrounding blown gas molecules, resulting in a highly ionized field that is forced onto the targeted surface. This highly ionized air stream creates a thermal property that reacts with the substrate and breaks the existing hydrogen bonds by introducing oxygen which recreates the chemical properties of the surface. The plasma process causes a molecular reaction on the substrate. It also creates finely etched and micro-cleaned surfaces resulting in better wettability, stronger bonding traits. See a video of PlasmaDyne Pro treating bottles in a trial here.
#3 Plasma surface treatment improves adhesion.
Plasma surface treatment modifies the surface of a material on a molecular level, enabling it to bond more readily with adhesives, ink, paint, and other media. It is effective on a variety of materials; even difficult-to-bond materials can achieve better adhesion without experiencing surface damage.
#4 Plasma treatment improves adhesion on a wide variety of materials.
Bonding problems are pervasive throughout manufacturing, especially the plastics industry. Manufacturing and decoration often include joining plastic-to-plastic, plastic-to-metal, plastic-to-composite and more. But, plastics and many other materials possess low surface energy or “wettability” and therefore, require plasma pretreatment.
Plasma treatment is a non-invasive, non-heat-based process that can be used on virtually any material. It encourages molecular bonding on surfaces, micro-cleans contaminants, and causes fine etching. Plasma treatment facilitates the bonding of adhesive, ink, paint, and other media to a range of substrates. These materials benefit from plasma treatment:
Rubber and Elastomers
Metals and alloys
#5 Many industries rely on plasma surface treatment for their products.
Plasma surface treatment is used to enhance the wettability, adhesion, and cleanliness of materials within numerous industries, including:
Aerospace: The aerospace industry uses plasma surface treatment on critical surfaces to enhance adhesive bonding.
Automotive and Transport: The automotive and transportation industries utilize plasma treatment to improve adhesive bonding between components and enhance paint and coating adhesion to a variety of substrates.
Consumer Goods: Plasma treatments enhance the functional and aesthetic quality of various consumer goods.
Electronics: Plasma treatments protect sensitive components within potting. Plasma treatment is nearly potential-free allowing plastics with embedded circuitry to be safely surface treated.
Medical and Biotech: Plasma treatment is used for raising surface energy and micro-cleaning surfaces to ensure optimal bonding between components and devices.
Packaging: Packaging materials, such as plastic films, cardboard, and plastics, are often plasma treated to promote adhesive and ink application during printing and labeling operations.
Printing: Printing operations integrate plasma treatments to enhance surface wettability to ensure precise, vivid, and long-lasting ink adhesion.
#6 Plasma surface treatment is versatile.
Due to its exceptional versatility, plasma treatment has become critical for a wide range of applications, such as:
Painting, coating, and printing for plastic products
Enhancing coating adhesion for polymer extrusions
Printing, painting, and coating rubber profiles
Cleaning the surface of aluminum and other metals
Improving adhesion of glue on cardboard products
Treating silicone foam to enhance adhesive application
Improving adhesion of paint and ink to composite materials
#7 The advantages of plasma treatment include speed, cost-efficiency, eco-friendliness, and more.
Plasma treatment offers a number of advantages over other treatment options. For example:
It is potential-free: Atmospheric plasma is potential-free, so the treatment process can be used in conductive, semi-conductive, and non-conductive applications.
It is effective for surface cleaning: Plasma can be used for micro-cleaning operations, which removes surface impurities and contaminants.
It is environmentally friendly: Plasma cleans and enhances material surfaces without the use of harmful chemicals or ozone emission.
It is cost-efficient: Plasma treatment reduces process time by improving bonding, increasing surface cleanliness and wettability. You spend less time processing the substrate and use less ink, paint, glue, or coating due to optimal adhesion. Less waste and scrap are created, plus our plasma systems have low energy costs.
#8 3DT is your go-to source for all plasma surface treatment products!
3DT is a leading provider of plasma surface treatment solutions. Equipped with more than three decades of experience, our experts will thoroughly discuss your application with you and help to select one of our standard PlasmaDye Pro systems or a custom-engineered PlasmaDyne Pro based on the requirements of your application. PlasmaDyne Pro can be customized for nearly any 3D or flat surface. We also offer product handling and automation.
Learn More About Plasma Surface Treatment From 3DT
Plasma surface treatment improves the surface properties of materials, which is why they are used in many industries and applications. To learn more ask the experts at 3DT. As an experienced manufacturer of plasma surface treatment systems, we can address any questions you may have about the process and our systems. If you need a plasma system for your facility, we’ve got you covered.
To learn more about our products and how they can benefit your components and materials, check out our PlasmaDyne Pro or contact us today.
SOFTAL Corona & Plasma GmbH is an industry leader in designing and producing groundbreaking corona and plasma surface treatments for various materials, including plastic film, labels, textiles, paper, panels, metal, and more. Over 60 years of experience have made SOFTAL one of the most important companies in the surface treatment area.
As SOFTAL has headquarters in Hamburg, Germany, 3DT LLC represents the company in sales, support, and service in North America. 3DT offers corona and plasma treatment systems for 2D and 3D applications, which 3DT and SOFTAL both manufacture.
Who Is SOFTAL?
SOFTAL was founded in the 1950s when the industrial use of corona technology was young. As that technology became essential to industries worldwide, SOFTAL led in its innovation and growth. Now a globally trusted company with patented processes, SOFTAL has mastered the manufacturing of premium bonding techniques for coatings, adhesives, and lacquers, increasing quality and productivity without primers.
Although industry needs have changed over time, the SOFTAL promise of “adhesion guaranteed” has remained constant. “Adhesion guaranteed” symbolizes what SOFTAL is all about: the adhesion of your product customized for your processes, materials, and budget. SOFTAL has over 250 BOPP treatment stations and has produced over 10,000 corona stations, making it one of the most knowledgeable suppliers in the world.
What Products Does SOFTAL Offer?
SOFTAL offers a variety of surface treatment products such as:
Corona treatment systems – SOFTAL manufactures a complete line of corona treatment stations that improve the adhesion of glues, printing inks, lacquers, and other coatings to the surface of multiple materials. During corona treatment, corona energy is created when a dielectric barrier discharge (DBD) fires in the gap between the electrode and the counter electrode, causing a chemical reaction on the material being treated resulting increased adhesive forces.
Plasma treatment systems – Plasma technology uses one or more high voltage electrodes which charge the surrounding blown gas molecules, resulting in a highly ionized field that is forced onto the targeted surface. This airstream, or plasma discharge, reacts with the substrate and breaks the existing hydrogen bonds altering the chemical properties of the surface. Plasma treatment is especially suited for functionalizing thicker and thermally sensitive material such as polymer foam and wide materials such as plastic sheets, glass and metal plates. Plasma is nearly potential-free allowing conductive materials, such as embedded electronics to be effectively treated.
Benefits of SOFTAL
SOFTAL offers several advantages to its customers worldwide:
Install and forget. SOFTAL understands that the bottom line for most companies is a product that works and is simple to maintain. Therefore, all of SOFTAL’s user-friendly, modular products are durable, safe, cost-efficient, and easy to fix and service.
Adhesion guaranteed. SOFTAL’s slogan of guaranteed adhesion means that no matter how large its customer base gets, it will never forget its roots or what matters to you. Its treatment systems are modular, so SOFTAL is constantly growing, improving, and developing new processes and systems for its customers’ benefit.
Customer-specific interfaces and solutions. Its hardware and software solutions enable SOFTAL to customize all of its systems to fit with your materials and processes. As a result, you can concentrate on your core competencies, and SOFTAL and 3DT will handle the surface treatment of your materials.
Reliable service. SOFTAL is proud of its strong reputation and high level of customer satisfaction. With its network of trained, worldwide professionals, like us here at 3DT, SOFTAL can be almost anywhere in a matter of hours to solve your problem.
SOFTAL Services With 3DT
SOFTAL’s reliable commitment to easy-to-maintain products, adhesion solutions, customized answers, and fast service has made them a strong partner for 3DT.
Through a range of comprehensive and custom services, 3DT utilizes its 30 years of experience in quality adhesive and surface treatment solutions to offer dedicated customer service. Recognized throughout the world for our innovations in plasma and corona surface treatments, we serve numerous industries, including the packaging, automotive, electrical, food and drug, and medical sectors.