Versatile coating for heavier applications
Knife-over-roll uses a fixed blade to meter coating fluid on the substrate as it passes over a backing roll. The gap determines wet film thickness, giving simple, direct coat weight control with a wide adjustment range.
Where knife-over-roll excels: heavier coat weights, higher-viscosity fluids, thicker or textured substrates including nonwovens, foams, and rough materials that gap-sensitive methods cannot handle.
How knife-over-roll coating works
The blade can be flat steel, a radius rod, or wire-wound rod — each producing different coating characteristics. Coat weight is adjusted by raising or lowering the blade. The adjustment range is wider than other methods.
How IMC engineers knife-over-roll stations
Precision blade adjustment with positive locking on rigid structural supports. Backing roll ground to controlled TIR tolerances. For compressible substrates, roll hardness and nip geometry are specified for the material. Solvent-based applications include enclosure and ventilation.
Applications
- Saturant coatings
- Heavy adhesive layers
- Nonwoven impregnation
- Thick-film coatings
- Rough-substrate applications