Lip surface geometry for slide bead coating

A slide bead coating apparatus having a bead region wherein a flowing liquid layer or plurality of flowing liquid layers is continuously applied to a moving substrate, said coating apparatus comprising:

• a means for defining a bead region wherein a flowing liquid layer or layers is continuously applied to a moving substrate;
• a roller, and associated drive means, for conveying said substrate longitudinally through said bead region;
• a means for continuously supplying said flowing liquid layer or layers to a slide surface of a coating head;
• a coating lip tip at the terminus of said slide surface of said coating head and within said bead region;
• and
• a lip surface extending from the coating lip tip down into the bead region opposite the moving substrate;
• wherein the coating apparatus further comprises:
• a break and associated offset in the lip surface capable of isolating the bead region from a reservoir of liquid below said break;
• said break being located 0.5-5.0 mm below said coating lip tip and forming an angle with said lip surface of at least 15.degree. in a direction away from said substrate, and the offset having an average depth at least 0.25 mm from the plane of the lip surface and being at least 0.5 mm long.