Abstract
In order to examine the surface distribution of polyacrylamide (PAM) or the in-plane distribution within a paper sheet, the latest microscopic ATR/FT-IR imaging analysis was adapted to the papers containing a PAM dry strength resin by means of the internal and external application methods. The variation of contacting situation with the ATR prism deeply affected on the microscopic ATR/FT-IR imaging of the surface of the papers. Thus, the some part of paper surface contacting with the prism was only available to examine the distribution. The imaging based on 1315 cm-1 absorbance assigned to cellulose showed the contacted area and the change of the absorbance indicated the contacting degree within the area. The imaging based on absorbance ratio of characteristic wave numbers for PAM and cellulose was useful to show the PAM distribution. Local uneven distribution of PAM was observed on the fiber surface in part for papers containing PAM made by both internal and external application methods.
