Perforated film

摘要

A perforated thermoplastic film with less than ideally shaped tapered capillaries which has an increased liquid flow rate through the tapered capillaries and a method for making such a film. The method includes forming a perforated thermoplastic film having tapered capillaries from a resin into which an effective amount of a polarizable, migrating surfactant has been blended therewith and then treating the perforated thermoplastic film with a corona discharge treatment sufficient to increase the flow rate of liquid through said perforated film and provide a film having a percent run off of from about zero to ten percent. The perforated film made in accordance with the invention has a much higher liquid transmission rate than similarly made non-surfactant treated perforated film having tapered capillaries which has been treated only with a corona discharge treatment. The latter may be conducted as the film is being formed and perforated.