Effect of Surface Chemistry on the Adhesion of Thermoplastic Polymers to Paper

Abstract

The sizing treatment of printing papers to make them resistant to penetration by liquids, for example, water or printing inks, also weakens the bond strength between the polymer and the paper in printing processes in which solid polymers create the image on plain, bond-type papers. The adhesion characteristics of a series of business papers treated with either rosin sizes or synthetic, cellulose-reactive sizing agents are described. It is demonstrated that the decrease in bond strength correlates with a decrease in paper wettability, as measured by capillary penetration of organic liquids of suitable surface tension, or as defined by surface energetics using the elution-gas-chromatography technique. Examples are presented, which show that these analytical techniques are effective in specifying paper performance in nonimpact printing technologies (for example, electrophotographic printing and resistive-ribbon, thermal-transfer imaging).