2001 年 48 巻 1 号 p. 27-36
In office paper recycling, image analysis is mainly used for the evaluation of toner-fiber separation. However, since only few thousand toner particles in maximum are usually measured, the assay precision as a toner determination method is questionable. In this study, a simple and convenient toner determination method has been studied using a small amount of sample by a transmitting spectrometer which is most widely used as a spectrometer. Also, the assay precision of image analysis for toner content has been examined. The assay precision of image analysis improved by correction for toner size distribution, and the correlation between toner content and measured toner area increased from r2=0.976 to r2=0.990. On the other hand, the correlation by measuring total transmittance using 0.15 g of sheeted sample was r2=0.993. The operation time of transmittance-measuring methods were half the time of image analysis. It has been proved that transmittance-measuring methods are convenient and highly precise methods for toner determination in recycling studies.