How Vacuum Web Coating Ensures Precision, Quality Coatings

Published: August 28, 2025

By Liz Josephson, VP Commercial Operations, Intellivation LLC.

Vacuum web coating is widely utilized across various industries for the deposition of thin films onto flexible substrates for barrier, optical or functional properties. This technology has become a cornerstone for applications ranging from packaging and electronics to optics and renewable energy. By operating in a vacuum environment, this technique ensures precision and quality coatings, allowing manufacturers to create products with enhanced functionality and performance.

Vacuum web coating involves the application of various coatings onto continuous rolls of flexible materials, such as plastic films, paper, flexible glass or metal foils, all commonly referred to as the substrate. The process is carried out in a vacuum chamber, where air and other gases are removed to create a controlled environment, minimizing contamination and enabling the deposition of high-quality coatings.

Vacuum coating uses Physical Vapor Deposition (PVD), enabling the deposition of thin films onto flexible substrates with high precision. Several PVD processes are employed, each offering unique advantages depending on the application and material requirements. Thermal Evaporation involves heating a material until it vaporizes in a vacuum chamber.

The vapor then condenses onto the substrate, forming a thin layer, nanometers thick. Thermal evaporation is commonly used for depositing metals like aluminum and silver, as well as reactive materials for optical coatings. Electron Beam Evaporation is a more advanced form of thermal evaporation; this technique uses a high powered, focused electron beam to heat and vaporize the coating material. It allows for high deposition rates and very good control over film thickness, making it ideal for applications requiring precise coatings at high rates such as clear barrier coatings.

Sputter Deposition uses high-energy ions to bombard a target material, ejecting atoms that then deposit onto the substrate. Sputtering is highly versatile and can be used to deposit metals, oxides, nitrides, multi-layers and other complex materials. It is widely used in electronics, optics and for very high barrier coatings.

There are different types of sputter magnetrons, such as RF and DC, which are used depending on the materials or layers required. Each of these PVD processes plays a crucial role in vacuum web coating, enabling industries to achieve high-performance coatings for packaging, electronics, optics, and renewable energy applications. During the web coating process, the substrates are unwound, coated and then rewound entirely in the vacuum chamber. Despite being a batch process, the intrinsic method of web coating directly enables large-scale production and cost efficiency by allowing long rolls to be run at high speeds up > 18 m/s for packaging and some barrier applications.

These coatings are primarily metallic based layers like aluminum or metal oxides that can be evaporated at high rates. Additional complex multilayer structures designed for specific optical or electrical functionalities can also be deposited using other plasma processes such as sputtering, PECVD or assisted plasma processes.

The versatility of vacuum web coating makes it indispensable in numerous industries. For barrier film for packaging, the vacuum coating creates a moisture and oxygen barriers on polymer films, ensuring product longevity. Flexible electronics and displays are enabled by anti-reflective and protective coatings for touch sensors and OLED displays. Battery performance can be enabled with Li deposition. Evaporation of capacitor coatings is one of the oldest usages for vacuum roll coating improving efficiency and durability of wound capacitors.

Aesthetic enhancements are in various consumer products such as holograms or color shifting packaging. Security applications can use similar layers and stacks to increase anti-counterfeit devices and variable optical properties. Energy applications like solar can use deposition technologies for barrier, conductive layer or optical properties.

Vacuum web coating offers several benefits that set it apart from other deposition techniques:

• Superior Coating Quality - The controlled vacuum environment ensures high-purity coatings with excellent adhesion and uniformity
• Precision & Consistency - Enables precise layer thickness control, making it ideal for applications requiring uniform coatings.
• Environmental Benefits - Compared to traditional coating methods, vacuum web coating is more eco-friendly, reducing chemical waste and emissions.
• Enhanced Durability - Improves the mechanical and chemical resistance of coated materials, extending their lifespan.
• Versatility - Can be applied to a wide range of substrates, including polymers, metals, and flexible glass.
• High Productivity - The roll-to-roll process allows for high-volume coating, increasing efficiency and throughput.

Despite its advantages, vacuum web coating also comes with challenges. These include the initial cost of equipment, complexity in maintaining vacuum conditions and limitations in coating certain substrates. Manufacturers must address these challenges through innovative approaches and ongoing research to expand the capabilities of this technology.

Development and use of new materials are broadening the application spectrum for vacuum coating including aerospace, long wavelength coatings, filters, shielding and reflective materials.

As industries continue to demand advanced materials with enhanced performance, vacuum web coating technology is evolving to meet these needs. Emerging trends include:

• Multifunctional Coatings - New coatings are being developed with properties such as antibacterial, anti-viral, wear resistance and thermal sustainability.
• Eco-Friendly Solutions - Sustainable and biodegradable coatings are gaining traction, reducing environmental impact.
• Improved Barrier Films - Enhanced permeation barrier coatings are being explored for packaging and electronics.
• Advanced Deposition Techniques - Innovations in sputtering, PECVD, and electron beam evaporation are improving coating precision and efficiency.
• Flexible Electronics & Photovoltaics - Vacuum web coating is playing a crucial role in the development of next-generation flexible displays and solar cells.

Vacuum web coating stands at the forefront of thin film deposition technology, empowering industries with the tools to create innovative and high-performance materials. Its ability to deliver precision, scalability, and versatility makes it an invaluable process for modern manufacturing. As advancements in this field continue to unfold, vacuum web coating will undoubtedly play a pivotal role in shaping the future of materials science and engineering.

About the Author

Liz Josephson joined Intellivation in 2021 with decades of experience in the Vacuum Web Coating industry supplying equipment and supporting projects including medical, barrier, flexible electronics, security and packaging applications in the Americas and globally. Previously at Applied Materials, responsible for their Vacuum Web Coating business in the Americas, Liz is current SVC President, Past President of ARC (formerly AIMCAL), founding Board Member of the SVC Foundation, active committee member, and has had several leadership positions in SVC and AIMCAL as well as local non-profits.