Material treating apparatus

Apparatus for treating lengthwise traveling material comprising a driving member, the material-contacting surface of said driving member being provided with a multiplicity of alternating grooves and lands extending parallel to the direction of drive of the material by the driving member, presser means to press said material against said surface of said driving member, feed means arranged to feed the material into driven engagement with said face of said driving member in advance of said presser means and cooperating with said presser means to maintain sufficient widthwise tension on the material to keep it smooth, so that it engages the lands and bridges the grooves of said surface of said driving member, and a retarding member for deflecting the material away from said driving member, located on the same side of the material as said driving member, said retarder member comprising a multiplicity of alternating teeth and slots, said teeth extending into said grooves of said driving member from fixed ends located beyond said presser means in the direction of drive of the material and having their free ends disposed in said grooves of said driving member surface with clearance from the walls of said grooves, said slots receiving therethrough the lands of said driving member surface with clearance from the walls of said slots.