A web or film is electrostatically charged by sequentially subjecting the web or film to a series of electric fields such that adjacent electric fields have substantially opposite polarities. Both a method and apparatus are disclosed for charging the web or film.
RELATED CASES
This application is a divisional application of U.S. application Ser. No. 08/426,031, filed Apr. 21, 1996, now U.S. Pat. No. 5,955,174, issued Sep. 21, 1999, which is a continuation in part of U.S. application Ser. No. 08/411,486, filed Mar. 28, 1995, now U.S. Pat. No. 5,686,050, issued Nov. 11, 1997, which is a continuation-in-part of application Ser. No. 07/958,958, filed Oct. 9, 1992, now U.S. Pat. No. 5,401,446, issued Mar. 28, 1995. The application and patents are incorporated herein in their entirety by reference.
