Slot Die System

Function/Description

The application of the coating raw material by a die system is another alternative. A die is a closed application system, consisting of a die chamber, into which the coating raw material is pumped. For each coating raw material, the design of the die is evaluated regarding the raw material“s flow behavior. This guarantees the raw material“s even outflow out of the die lips.
A special micro pump feeds highly precise meterings of the coating material to the die. The coating weight can be precisely defined by the speed of the pump. Also the die lips and the speed of the web influence the coating weight.

The advantages of the die system are:

• a closed system, advantageous for the processing of solvent-based systems and with regard to the cleanness of the application
• depending on the viscosity of the raw material, very thin layers of under 5 µm can be realised, but layer thicknesses of up to 300 µm are also possible
• realisation of intermitting coatings
• the coating can be realised either with a contact of the die to the substrate, but also contactless.

The use of the die technology grows constantly, as the application of coating materials needs to become increasingly precise.

Examples