Gloss Measurement of Papers: A Comparative Study

The performance of the Bausch and Lomb and Sheen glossmeters is examined. Comparison of gradings of nine printing papers according to visual and instrumental means shows that, despite high correlation between them, there are nevertheless important discrepancies not attributable to sampling, instrumental or personal errors. The effect of angle of incidence and viewing on grading is investigated; best results are noted at 45°, and the discrepancies become more pronounced at greater angles. Gradings of the same papers according to the Jones, Askania, Goerz, Ostwald and Klughardt methods are examined; all are found unsatisfactory. It is concluded that, for the limited range of papers tested, the most satisfactory grading is given by measurements of the intensity of light received when angles of incidence and viewing are 45°.