Fluid Coating

Various substrates such as paper, plastic films and metal foils certainly have value, but deposit a coating on those substrates and now you have a “value added” product.  EDI’s Ultracoat® and Liberty® Slot Die Coating Technology is the key to those value added processes.

Coaters and converters alike can reap the benefits utilizing slot dies for applying low-viscosity wet coatings.  EDI Dies, Support Systems and Die Positioner Systems, Modular Coating Stations and Fluid Delivery Systems provide greater precision than traditional roll coating systems.

The key advantages to using EDI Slot Die Technology are:

Increased Production Rates
A Positive displacement pump delivers a constant supply of coating fluid to the slot die.  The coating fluid may also be modified to contain a higher solids content, which decreases the workload of drying units, leading to increased line speeds.

Positive Coat Weight Control
Again the positive displacement pump delivers a constant supply of coating fluid per unit time.  Variations in coat weight are controlled by regulating the pumping rate to line speed ratio.

Cross-Web Distribution Control
The manifold geometry is designed to uniformly distribute the coating fluid, based on the fluid’s rheology.  While the lip adjustment system is used to fine tune the cross-web distribution as the fluid exits the slot die.  Furthermore, the Support and Positioning system plays a key roll in accurately and precisely positioning the slot die relative to the back-up roll.  Also for processes that need to operate at elevated temperature, multiple heating zones are provided for optimum heat control.  Increased heat control promotes uniform fluid viscosity contributing to uniform cross-web coating distribution.

Improved Waste Management
Productivity can increase due to the reduction in waste.  Slot die coating systems are closed systems.  Meaning there are no open pans or troughs, which are typically open to contamination.  Also, being a closed, pre-metered, system 100% of the coating fluid is applied to the substrate via the positive displacement pump and the slot in the die exit.  There is no need to overcoat and collect a waste stream.