Surface characterization of a rosin sizing agent in paper by means of EPMA, ESCA and TOF-SIMS

EPMA(e1ectronprobe micro analysis), ESCA (electron spectroscopy for chemical analysis) and TOF-SIMS (time of flight type secondary ion mass spectrometry) were used to detect the distribution of a rosin sizing agent in paper. For EPMA we labelled paper samples with osmium tetroxide which enabled the detection of rosin in the XY direction of the paper sheet. For ESCA we labelled paper samples with fluorine which also enabled the detection of rosin. At the same time, the ESCA angle-dependent technique was used to obtain depth profiles of the rosin. Also, distribution images of rosin on an extremely thin ( 1 nm) surface layer were made observable by monitoring fragment ions from the rosin with TOF-SIMS. By using EPMA, a notable difference in rosin distribution was shown on the pulp fiber. However, according to the TOF-SIMS examination, the rosin was shown to be distributed relatively even in an extremely thin surface layer. The ESCA angle- dependent technique showed that rosin was present mainly on the outer surface layer.