Patent attributes
A peripheral surface of a coating rod has an area where grooves (convex portions) are formed. This area is ground by a grinding apparatus by which a maximum height Ry of the rod surface is adjusted to 15 μm or less. Further, a ratio of D/W is adjusted to 0.01 or more, wherein D is a total distance of the convex portions of the rod actually abutting on a web in an axial direction of the rod, and W is a coating width of the web. Furthermore, straightness of the rod is adjusted to 30 μm or less per 1 m, and roundness of the rod is adjusted to 10 μm or less. Micro-projections are removed by grinding so that scratches of a coating surface are prevented from occurring. Coating unevenness is prevented by improving the straightness and the roundness.