Gloss of Machine Glazed Papers

The flux I 0 reflected at specular angles 45°–45° from the surface of glossy paper and the assumed value of its diffuse component I 2 defined experimentally are measured with a goniophotometer. The ratio of I 0 to I 2 is taken as a measure of gloss, and denoted by G N F according to an earlier paper of E. Fukushima. 1) For a series of machine glazed papers differing considerably in colour, the values of C N F are compared with the visual gradings of 36 Japanese observers, and a linear correlation of the logarithm of G N F with the visual gloss is found with a correlation coefficient +0.986 except for two papers. The method of determining the value of I 2 is also introduced and the voting distributions of the observers for the gloss of the papers are discussed.