Coating process

摘要

The invention relates to a coating process using a coating apparatus of an extruder type, having a rear edge face and a stripping border face, in order that a coating medium is applied as a strand under constant pressure from a gap, which is formed between the rear edge face and the stripping border face, onto a surface of a flexible holder which runs uninterruptedly both over the rear edge face and over the stripping border face. The stripping border face is arranged on the side of the running holder lying downstream in the flow direction in such a way that a single plane or a curved surface with only one radius of curvature is produced; if a point A represents an end of the stripping border lying downstream in the flow direction and the point B represents the uppermost part of the gap at the rear edge face, therefore a line AB joining the points A and B which does not intersect the stripping border face is achieved. An angle theta 1 lies between a tangent to the rear edge face at the point B and the line AB and an angle theta 2 lies between the line AB and the holder which extends downwards from the point A in the flow direction. The angles theta 1 and theta 2 meet the conditions: 150@ < theta 1 < 180@ and 150@ < theta 2 < 180@; therefore, the thickness range of the coating film to be supplied is set by altering the angle theta 2.