Film coating appts. for tape or strip materials - has extrusion head with exit having wavy line profile to aid distribution and achieve uniform film thickness

摘要

A coating process of a type suitable for forming a thin layer of magnetic recording material on a carrier film has a head consisting of a leading element (2) and a lagging element (3). The top edges (9, 10) of the elements are formed with an undulating profile that aids the formation of a uniform, thickness film. As the carrier film (1) is moved across the surface, a precoating layer (11) is distributed. This is of a low viscosity substance. The surface coating mixture (7) is extruded through the main channel (8) and forms a layer of defined thickness. USE/ADVANTAGE - Forms uniform film thickness.