Tag Archive: surface treatment

1. How Surface Treatment Functionalizes & Activates Difficult Bonding Surfaces

   August 4, 2022 6:30 pm Leave a Comment

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   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 surface for 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.

   3DT works closely with its customers in selecting the most appropriate surface treatment method for their application. Factors such as the materials and media involved, the geometry, line speed, and required bonding results are considered. See our blog article What is the Process for Purchasing a Surface Treatment System from 3DT? for more information.

   

   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. 
   

2. Corona vs. Plasma Treatment

   July 23, 2021 9:59 pm Leave a Comment

   For more than 30 years, 3DT LLC has been a leading provider of specialized corona and plasma surface treatments for customers around the world. Our state-of-the-art systems can be used as stand-alone stations, incorporated into new and existing production processes, or integrated into fully or semi-automated production lines. With 3DT’s 2- and 3- dimensional treating systems and a wide variety of custom configurations, we have a solution for virtually any application. In addition to manufacturing our cutting-edge equipment, we offer services such as design, manufacturing, product handling, installation, training, and maintenance service.

   One of the more common questions we field about electrical surface treatment is, “What is the difference between corona and plasma treatment?” and then, “What best fits my application?” Both corona and plasma treatment increase the surface energy of numerous materials improving the adhesion of inks, adhesives, coatings, and other agents. However, they both have unique properties that require consideration in terms of applications.

   

   In this post, we discuss the advantages and uses of corona treatment vs. plasma treatment, to aide in your understanding. However, our sales team will actively guide you in selecting the best system for your material, process and application.

   What is Corona & Plasma Treatment?

   How Does it Work?

   Corona and plasma treatment are both forms of electrical surface treatment. They use the power of electrical energy to change the chemical properties of material placed within an energy stream. This stream of electrically loaded molecules causes an intensified reaction with the material resulting in better wettability and stronger bonding traits. Electrical surface treatment is highly suitable for three-dimensional polymer parts, thin film, rubber profiles, glass labware, metal parts, coated paperboard and thicker materials such as foam and solid sheets of material.

   When this phenomenon is contained inside an electrically grounded chamber, an air stream can be introduced to this chamber to force the plasma outwards in a controlled fashion and onto materials in a process called plasma treatment or atmospheric plasma treatment. However, when an insulator is placed between the two electrodes, the avalanche effect is avoided and the result is a cloud or arc of ionized air. This ionized air – Corona Discharge – can now be used for the surface treatment of a wide number of materials that show poor or no adhesion properties to media such as printing inks, adhesives, etc.

    

   

                                            Illustration: Corona Treating Head

   What’s the Difference Between Corona & Plasma Treatment?

   Plasma discharge has a relatively narrow treating width but is capable of imparting enormous surface energies onto substrates.  Plasma has the added benefit of cleaning residue and contaminants from surfaces and even etches surfaces for the added benefit of increasing bonding with media. Plasma discharge is virtually potential-free so it can be used to treat conductive materials such as metal and alloys. 3DT’s PlasmaDyne systems offer a variety of types of plasma treating heads that can be quickly mounted onto existing lines with little setup. A unique benefit of our system is that the discharge level is adjustable for numerous applications. Plasma also produces no ozone gas which is a natural byproduct of the corona process.

   Alternatively, corona discharge typically imparts less surface energy but can treat large areas. Corona treatment also has the advantage of being able to treat inside parts or in the recesses of 3-dimensional parts. Both methods are very effective in functionalizing surfaces for better adhesion. Check out the video below.

   Our Most Popular Treatment Systems

   3DT designs and manufactures an extensive range of cutting-edge surface treatment products, including:

   MultiDyne™

   3DT’s MultiDyne™ corona treatment system creates optimal surface tension, or wettability, on a broad range of parts and materials. Featuring repeatable and process controlled operation,  MultiDyne™ is typically used to prepare blow molded, injection molded, and extruded parts and products. MultiDyne™ creates highly effective, uniform adhesion on surfaces for printing, coating, gluing, and lamination.

   MultiDyne™’s state-of-the-art corona discharge technology works by creating a short circuit between two high voltage electrodes. A constant flow of air between the electrodes facilitates even distribution of the corona field onto the surface of the treated material, creating a highly receptive adhesive surface. It is perfect for treating areas that are commonly a challenge for other surface treatments, including applications with complex geometries, hard-to-reach areas, and metal-adjacent surfaces.

   PolyDyne™

   PolyDyne™ is one of 3DT’s most powerful corona treatment systems. This extremely dependable and reliable system is particularly useful in high-speed operations, such as printing, extrusion, assembly, and coating production lines. PolyDyne™ is exceptionally versatile and can be used to treat everything from the interior surface of needle hubs to automotive components. Using the latest technology, PolyDyne™ directs corona treatment with an exceptional degree of precision onto virtually any surface.

   PolyDyne™ is specifically designed with flexibility in mind. All of our systems can be customized to meet the particular needs of your application, including variety and number of treating heads, custom electrode systems, ozone eliminators, and material handling systems. For more resistant materials, we are pleased to offer our PolyDyne Pro™ system.

   PlasmaDyne Pro™

   

   PlasmaDyne Pro™ uses a stream of highly ionized plasma to modify the chemical properties of the surface material within the stream. The surface becomes functionalized and highly receptive to chemical bonding. This system also cleans and etches substrates for added bonding properties. PlasmaDyne Pro™ is unique within the industry because only 3DT’s technology offers adjustable treatment/power levels. This benefit increases treatment options regarding flexibility in substrates, parts, and treating modes all within one system.

   PlasmaDyne Pro™ enhances the adhesion of ink, paint and adhesive to a wide range of components, from plastic tubing and medical devices to rubber automotive seals and metal parts. 3DT’s PlasmaDyne Pro™ is a compact, versatile system, with an optimized control unit, the highest in treatment levels and modular replacement parts that facilitate non-stop production. PlasmaDyne Pro™ is completely customizable. Let’s discuss your application today!

   Premium Surface Treatment Systems by 3DT

   At 3DT, we are committed to developing superior surface treatment systems for every industry.  We have spent decades at the forefront of corona and plasma technology and are dedicated to solving even the most complex adhesion challenges. To learn more about our surface treatment systems and related services, visit our product page, or contact our experts today.