What Are Knife Over Roll Coating Systems?

A knife over roll coating system is designed to use a knife with a roll or other mechanism to feed the material over a specified substrate for even application. Excess materials are scraped off as the substrate is fed through this system to provide a low cost, uniform covering for various weights or viscosities. It is a common approach as the method is acceptable for numerous substrates and types of coatings. What exactly does a knife over roll coating system do and when is this application method appropriate? First, it is a suitable option for materials with a higher viscosity or weight as adjustments are easy to make during production. Knife over roll coating systems are lower cost equipment with highly flexible attributes. Whether the objective is to create a pressure sensitive covering or to add a topcoat, this application process is able to get the job done. The method is used for a multitude of covering applications including:

• Heat/Solvent Reactivated
• Pressure Sensitive
• Barriers
• Primers
• Plastisol
• Latex

The gap between the knife and roll within these systems may be adjusted to accommodate different viscosity or weights. Viscosity is often best understood by thinking about the thickness of the covering, which may vary significantly per coating. An ability to adjust how much goes through the gap ensures that these variations are not a problem. Knife over roll coating systems are also designed to handle more weight than other application choices making them ideal in a number of scenarios. When Is This Method Most Beneficial? Knife over roll coating systems are quite beneficial for certain covering requirements and materials. As one of many available roll systems, it offers the ability to rearrange the gap for further customization and allows providers to deliver the desired quality quite easily. These systems are often considered to be the all-around workhorse of coating manufacturing and application since they are able to handle multiple configurations. They make a great choice for adding films or foils consisting of various water or solvent-based adhesives. A few of the benefits of this application method include:

• Minimal Stress
• Minimal Viscosity Limitations
• Suitable for Extensive Weight Range
• Dependable Reproduction of Coating Weight
• Able to Perform at High Speeds
• Simple to Operate
• Cost Effective

In order to know if knife over roll is best for your specific needs, a few requirements must be evaluated. The coater must be able to meet the speed, weight, solid range, viscosity range, and desired appearance for the required covering material as well as substrate. If it cannot meet these demands, then another method might be needed to achieve the best results. Selection of materials and processes for a substrate is a big job, which is why most companies choose to work with a qualified, experienced provider of these services. This ensures the right decisions are made when desiring a low cost, effective, and high quality coating. If you want to learn more about knife over roll coating systems or another application option, contact one of our experts at Jessup MFG. We will help you understand offered processes, materials, and services to ensure you get exactly what is needed in a coating.