Abstract:

In this paper,the fractal characteristics of paper surface and the feasibility to use fractal dimension tocharacterize the micro-topography of paper surface are investigated through AFM to acquire the micro-topographydata and through Heron formula to optimize the algorithm on the fractal dimension.Then,the distribution homogeneityof surface height is evaluated with the average value of standard deviations of ＲMS roughness in differentscales and at different angles as parameter,and the effects of the gloss coating and the vacuum aluminizing onmicro-topography are discussed.The results show that ( 1) the fractal dimension based on the original algorithmexceeds the theoretical value while that based on the optimized algorithm is within the range of theoretical value;( 2) paper surface displays fractal characteristics and optimized fractal dimension can be used to characterize thesurface of micro-topography; ( 3) the higher fractal dimension is,the more complicated surface of micro-topographywill be; and ( 4) when a coating weight is 3 g /m2,the gloss coating do not affect the fractal dimension but causesthe homogeneity parameter of superficial height distribution to decrease from 4.05 nm to 2.11 nm,and the vacuumaluminizing causes the fractal dimension to decrease from 2.58 to 2.21.In addition,the homogeneity parameter ofsuperficial height distribution reduces from 2.54 nm to 0.78 nm．

Key words: paper, fractal dimension, topography, roughness