Adhesive Applications

Custom Adhesive Coating: Moving Technology Forward

When product developers and researchers break new design barriers, supporting technologies and solutions do not always keep up with new requirements for their innovations – and that includes off-the-shelf pressure-sensitive adhesive (PSA) tapes. That creates opportunities for custom adhesive coating technologies to step in. At Adhesive Applications, we design and manufacture adhesive-coated products to solve problems that didn’t exist previously, with custom adhesive coating runs at a scale that can support an emerging technology.

What is Custom Adhesive Coating?
Whether a customer’s specifications call for unique material application and specialized performance, or just a minor customization of an existing product, situations arise where the existing marketplace doesn’t offer a solution that fits the problem. In these cases, custom coating is the best option – to include the right adhesive, construction, and processing to meet the demands of the application – even down to the format and packaging of the finished product.

Adhesive Tape Constructions
Custom-coated tapes can be provided as single-coated (with a substrate on one side); double-coated (adhesive applied to both sides of a substrate); or as an unsupported transfer tape (essentially a layer of adhesive without a substrate, almost like glue in tape form.) The decision as to which is the best option will depend on the performance requirements of the application.

Adhesive Types and Their Characteristics
In addition, the type of adhesive is critical to the end result. Rubber adhesive can provide high adhesion, even to low surface energy materials, but is generally limited to a narrow temperature range. Silicone adhesive has unique characteristics – it’s the only chemistry capable of reliable bonding to silicone materials, and offers an extremely broad temperature and environmental performance range – but generally demands a higher price. Acrylic adhesive is versatile and used extensively for this reason. Acrylics can be formulated to provide a wide range of performance characteristics, at a reasonable price.

Custom Adhesive Coating Processes
Several different types of custom adhesive coating processes can be used to manufacture new products: reverse roll coating, slot die coating, and gravure coating. Here’s a look at each of these custom adhesive coating technologies:

Custom Adhesive Coating - Reverse Roll Diagram
Custom Adhesive Coating – Reverse Roll Diagram

Reverse Roll Coating
Reverse roll coating is one of the most popular types of custom adhesive coatings due to its efficiency and precision. Two cylindrical rolls move in opposite directions. One roll transports the substrate to be coated – this could be a paper, film, or fabric; and may be supplied by Adhesive Applications or by a customer. The other roll applies a metered quantity of adhesive onto the substrate.

As the rolls rotate in opposite directions, they’re brought into close proximity to wipe the adhesive onto the substrate, resulting in even deposition of the adhesive material on the substrate surface. A benefit of this type of technology is its speed – Adhesive Applications can sustain line speeds of up to 115 feet per minute, depending on coat weight and material. Our coaters can spread adhesive at as little as 0.5 mil up to 6.0 mil (12 – 150 μm). The coaters can handle materials up to 63 inches wide.

Custom Adhesive Coating - Slot Die Diagram

Custom Adhesive Coating – Slot Die Diagram

Slot Die Coating
Slot die coating is another popular custom adhesive coating technology, in which a thin layer of adhesive is extruded through a slit-shaped die onto a substrate surface. This type of technology offers excellent control over thickness and – meaning it can produce thin layers with little variation in thickness, in both the cross-machine and down-machine directions. Additionally, slot die coating can provide high-speed application rates (up to 500 feet per minute). However, this type of technology requires significant set-up time and maintenance that can impact cost. Adhesive Applications has purchased a hot melt coater with UV curing capability that will coat through a heated slot die process (also with a 63 inch maximum web width) expected to be operational in Q2 of 2023.

Each type of custom adhesive coatings technology offers unique advantages and drawbacks depending on your project requirements. The Adhesive Applications team can look at those requirements and work with customers to develop the right coated product. Working with our Product Development Director, our Lab, and our experienced Production team, Adhesive Applications customers collaborate with us to develop solutions tailored to their design challenges. From consulting, to lab samples, to trial runs, our team partners with researchers and engineers to create the right adhesive tape product for new innovations. Call or email an expert at Adhesive Applications to discuss our custom adhesive tape solutions at (413) 527-7120 or info@adhesiveapps.com.