Standard Test Method for Yellowness Index of Plastics
|Publication Date:||22 January 1970|
This test method is intended primarily for determining the degree of yellowness (or change of degree of yellowness) under day-light illumination of homogeneous, nonfluorescent, nearly colorless transparent or nearly white translucent or opaque plastics. It is applicable to transmittance of transparent and translucent plastics and to reflectance of opaque plastics (Note 1). It is based upon tristimulus values calculated from data obtained on the Hardy-G.E.-type spectrophotometer,2 but other apparatus is satisfactory if equivalent results are obtained.
The values stated in SI units are to be regarded as the standard.
NOTE 1-This test method has not been demonstrated for the determination of transmitted yellowness of plastics having a luminous transmittance below 25 %, and it has not been demonstrated for the determination of reflected yellowness of translucent plastics.
This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2 This spectrophotometer is described in Recommended Practice E 308. It is available as the Diano/Hardy Recording Spectrophotometer manufactured by the Diano Corp., P.O. Box 346, 75 Forbes Blvd., Mansfield, MA 02048.