Techniques for Deinking Electrostatic Printed Office Waste Paper, 1995 Recycling Symposium Proceedings

Chin Li

Kevin Hipolit

David A. Longhini

Richard E. Freis

PPG Industries, Inc.

Office wastepaper is an underutilized source of woodfree post-consumer waste primarily because it is usually heavily contaminated with electrostatic printed inks. Removal of these inks by conventional deinking techniques remains a challenge because of the chemical and physical differences of these inks when compared with other ink types. PPG Industries, Inc. has successfully applied flotation and patented agglomeration processes to deink wastepaper grades contaminated with electrostatic inks. The first technique, flotation, represents a traditional deinking method that requires modifications in the deinking chemistry to effectively remove electrostatic inks. The second method, agglomeration, represents a non-traditional approach to deinking that has proven to be effective in recycling office wastepaper. Both techniques are being used in commercial operations today.