Quantifying emulsified wax distribution on wood flakes.

A wax distribution quantification procedure using digital image analysis and fluorescence microscopy techniques was developed for use with lignosulfonate-based wax emulsions. The procedure was evaluated by investigating the effect that variable application rates may have on wax distribution, and if wax distribution influences the dimensional stability of flakeboard. Application flow rate and pressure was shown to significantly affect both 2-hour and 24-hour water absorption (by weight), with increased application parameters resulting in decreased performance. Differences in 24-hour thickness swell were also seen between panels made using increased flow rate and pressure and panels produced with standard parameters. Wax emulsion flow rate and application pressure also had a significant influence on wax coverage and wax spot size distribution. The presence of liquid phenol-formaldehyde on the flakes increased measured wax coverage variability.