Method for applying continuous longitudinal bands of liquid coating to a moving strip

Claim 1

A method for applying continuous longitudinally extending bands of a liquid coating to a moving strip which comprises providing an elongated coating element having a convex outer surface, there being lands formed in said convex surface in a number corresponding at least to the number of coating bands to be applied, said lands having a width such as to yield the desired band coating width, said lands extending in encircling courses about the long axis of said coating element, each land being defined by a pair of grooves extending inwardly of said convex surface all of said grooves being disposed parallel with each other and transversely of said long axis, said coating element further having a central axial passage therein and radial passages connecting, with the central passage and outletting at an opening in the convex surface of each of said lands, the number of said openings corresponding to the number of bands to be applied at the convex surfaces of said lands, and fixedly disposing said element with its long axis extending transversely of the direction of the travel of the strip whereby the convex surfaces of said lands extend in the direction of strip travel, advancing the moving strip in a lead in-lead off contacting engagement with the convex surfaces of said lands, fixing the positioning of said coating element in an orientation relative to the moving strip such as to provide that the openings at the convex surfaces of said lands are located adjacent to but downstream of the point of lead-off contact of the moving strip with the convex surfaces of said lands, and feeding the coating material through said central passage and radial passages for outflow delivery of same at the openings at the convex surfaces of said lands, whereby there is established with the liquid outflowing from each of said openings a meniscus of liquid coating which contacts the said convex surface of each of said lands and said strip downstream of said point of lead-off contact, said meniscus being broken off sharply at the groove surfaces adjacent each of said lands, thereby causing said bands to be applied to said strip.

Claim 2

A method for applying continuous longitudinally extending bands of a liquid coating to a moving strip which comprises providing an elongated coating element having a convex outer surface, there being lands formed in said convex surface in a number corresponding at least to the number of coating bands to be applied, said lands having a width such as to yield the desired band coating width, said lands extending in encircling courses about the long axis of said coating element, each land being defined by a pair of grooves extending inwardly of said convex surface all of said grooves being disposed parallel with each other and transversely of said long axis, said coating element further having a central axial passage therein and radial passages connecting, with the central passage and outletting at an opening in the convex surface of each of said lands, the number of said openings corresponding to the number of bands to be applied at the convex surfaces of said lands, and fixedly disposing said element with its long axis extending transversely of the direction of the travel of the strip whereby the convex surfaces of said lands extend in the direction of strip travel, advancing the moving strip in a lead in-lead off contacting engagement with the convex surfaces of said lands, fixing the positioning of said coating element in an orientation relative to the moving strip such as to provide that the openings at the convex surfaces of said lands are located adjacent to but downstream of the point of lead-off contact of the moving strip with the convex surfaces of said lands, and feeding the coating material through said central passage and radial passages for outflow delivery of same at the openings at the convex surfaces of said lands, whereby there is established with the liquid outflowing from each of said openings a meniscus of liquid coating which contacts the said convex surface of each of said lands and said strip downstream of said point of lead-off contact, said meniscus being broken off sharply at the groove surfaces adjacent each of said lands, thereby causing said bands to be applied to said strip.