Manufacture of a textile-like reticular product from thermoplastic film

A process for the direct conversion of thermoplastic film material into open-work sheet material having fibers on one surface thereof, which comprises the steps of maintaining one surface of a length of such film material into face-to-face contact with a surface capable of adhering to said thermoplastic material when the latter is in molten condition, while said surface is heated in a pattern of heated surface regions separated by unheated surface regions to a temperature above the melting point of the film material;

• continuing the contact between the film surface and the selectively heated surface for a time sufficient to selectively melt the film areas contacting said heated surface regions, whereby said melted film areas adhere to said surface regions, while the remaining film areas remain in generally unmelted and nonadhering condition;
• then separating said selectively molten film from contact with said selectively heated surface whereby the molten adhering film areas are drawn out from the remainder of the film as fiber-like projections extending from the surrounding unmelted margins and thereby create apertures in said film generally corresponding to said heated surface regions;
• and directing a flow of cooling air toward the surfaces undergoing each separation to control the drawing of said fiber-like projections.