Process of producing magnetic recording tape having textured backcoat

摘要

Coated polymeric sheet comprising polymer substrate a cross-linked polymer, wherein the coating is characterized by: A. being smooth, having a surface roughness not greater than 0.05 nanometers Ra, except that; B. in the otherwise smooth surface, a multiplicity of depressions having depth ranging from 1 to 90% of the thickness of the coating. Backside coatings (containing carbon black in the cross-linked polymer) for magnetic recording tapes benefit from this invention by improved winding characteristics. The concept described is a replacement for rough random surface texture, formerly used in backside coatings, with a controlled surface texture. The process disclosed can also be used to make alphanumeric symbols on the pigment binder coating.