Roll-to-roll coater

Sourcing a High-Quality Roll-to-Roll Coater

Roll coating is a continuous fabrication process of applying an external coating to the base, intermediate, or top layer of a coiled flat substrate using rollers. Roll coating aims to enhance the substrate surface properties by adding adhesion properties or protection against harmful exposures or countless other modifications through the application of a relatively thin layer of chemistry. The following guide can help you in sourcing a high-quality service or manufacturing company known as a roll-to-roll coater.

Types of Roll-to-Roll Coating

We have covered the various types of roll-to-roll coating for a better understanding of the fabrication process.

Air Knife Coating

In air knife coating, a wet coating is applied to a substrate and an air jet brushes off the excess material from the substrate’s surface to leave the desired amount.

Knife-Over-Roll (KOR) Coating

In knife-over-roll (KOR) coating, a coating blade is set to a known gap over a roll which determines the wet thickness of the coating allowed to pass through on the substrate’s surface.

Hot Melt Coating

Hot melt coating uses heat to melt a thermoplastic coating material which is usually applied on a substrate by a slot die which then cools and solidifies to the final desired thickness on the substrate.

Immersion Coating or Dip Coating  

In immersion coating, the substrate is dipped/immersed continuously in a wet bath to saturate the substrate on both sides which is then sometimes metered to leave the desired wet weight.

Metering Rod Coating

This type of coating method uses an applicator roll to apply an excess of wet coating which is then metered back to the desired wet thickness by a wire wound rod or grooved rod on the substrate.

Slot-Die Coating

Slot-die coating relies on a narrow deposition slot to apply a pre-metered layer of wet material on the substrate surface.

Curtain Coating

Curtain coating is a pre-metered method that forms a curtain of the wet coating material that is cascaded onto the substrate surface.

What to Look for in a Roll-to-Roll Coater?

Here are a few indicators that can help you find an excellent roll-to-roll coater.

The experience of a roll coater

Roll-to-Roll coating is a technical task requiring your supplier to be skillful and experienced. The more experienced they are, the more efficient and better their work. You should pay particular attention to those coaters that can demonstrate experience with the varying coating types as described above.

The time and diversity of the business in the industry

A business that has been in the running for a long time and provides a diverse range of services has gained more experience and is likely to perform better. Typically, a minimum of 10 years of proven success in the business should give you the confidence they will perform at the highest levels required.

Roll-to-roll coater capacity

It is essential to know the capacity of your roll coater, especially if you are working on large-scale production. The roll coater should be able to meet your daily or monthly quota. As they say, time is money and if your coater protracts the time to delivery, this is costing you money.

The capabilities of a roll coater

As you saw before, there are different kinds of roll-to-roll coating methods and depending on the one you require; you must choose a roll coater that is capable and has mastered the process.

The equipment used for roll coating

Roll-to-Roll coating requires specialized equipment to ensure proper coating. Your roll coater should have well maintained coating equipment and work environment to provide the best product. Conduct an audit of their equipment to ensure they are up to the task.

The qualification and experience of the trained staff

A business is only as good as its people. Check for training certifications, experience, types of coating they do, and customer reviews that can help you assess their qualifications. Again, the equipment is only as good as the engineers and technicians running the process.


Finding a reliable roll-to-roll coater is a tricky process that requires proper knowledge and careful consideration. If you need help with roll coating services, our professional staff can take the burden off your shoulders.

National Polymer is a leading R&D and manufacturing company specializing in roll-to-roll coating, formulation chemistry, deformulation, reformulation, engineered coating technologies, batch optimization, pilot coating, and production.  To learn more about our capabilities, call us today at (800) 679.0477.