IS 13360 : Part 9 : Sec 9 : 2001 Plastics - Methods of Testing - Part 9 : Optical Properties - Section 9 : Determination of Yellow Index of Plastics

1. Scope

1.1 This standard (Part 9/See 9) prescribes the method for determining the degree of yellowness (or change of degree of yellowness) under day-light illumination of homogeneous, non-fluorescent, nearly colorlesstransparent or nearly white translucent or opaque plastics. It is applicable to transmittance of transparent and translucent plastics. and to reflectance of opaque plastics. It is based upon tristimulus values calculated from data obtained on the Hardy -G.E. type spectrophotometer, but other apparatus is satisfactory if equivalent results are obtained.

1.2 This test method has not been demonstrated for the determination of transmitted yellowness of plastics having a luminous transmittance below 25 percent, and it has not been demonstrated for the determination of reflected yellowness of translucent plastics.