Determination of post-it(R) note adhesive particle size in handsheets and filter paper by image analysis

Pilot scale repulpability trials of Post-it(R) notes were conducted at the Black Clawson Co. Image analysis was used to measure the adhesive particle sized distribution in handsheets and in filter paper samples made from the outputs of the unit operations during repulping. The paper was stained with and adhesive selective purple dye mixture and immersed in a perfluoro-octane index matching solvent prior to analysis. Image analysis measured the number and volume particle size distributions, number average diameter, median diameter, Sauter average diameter, volume average diameter, and counts per unit area. Projected area percent was also measured by image analysis and compared with solvent extraction for determination of total adhesive content. Application:This study presents a useful method for measuring the size distribution of adhesive particles in handsheets from adhesive repulpability studies.