Coating device

A coating device for coating moving material webs running over a backing roll with an axis, and having an entrance side, an exit side and connected to a pressurized coating chamber, said coating device comprising:

• a pressurized coating chamber;
• a doctor blade at said exit side;
• an entrance side front wall movably mounted relative a front wall support cooperating with said backing roll to define a discharge gap;
• sideways sealing elements cooperating with said doctor blade and entrance side front wall defining and sealing an application space except for said discharge gap;
• a primary feed channel communicating between said pressurized coating chamber and said application space for transferring coating mixture therebetween;
• and
• an elongate baffle parallel to the backing roll axis and disposed at a small acute angle with respect to the backing roll in proximity to said entrance side front wall, said baffle having an elongate backing roll side and an elongate front wall side opposite said backing roll side;
• said baffle backing roll side cooperating with said backing roll to define an elongate hydrodynamic pressure gap therebetween having a length substantially equal to that of the elongate backing roll side of said baffle;
• said baffle front wall side cooperating with said front wall to define a secondary gap-shaped feed channel for communication of a surplus of the coating mixture between said application space and said hydrodynamic pressure gap, said hydrodynamic pressure gap comprising a return entrance to said application space for said coating mixture.