Signification et utilisation
5.1 This practice should only be used to compare samples of the same material and the same general appearance. Par exemple, a range of specimens to be compared should have roughly similar lustre, texture et (sinon opaque) thickness and semi-transparency.
5.2 Pour les mesures de jaunissement, this practice is limited to samples whose main wavelength is in the range 570 to 580nm or whose Munsell hue is approximately 2.5GY to 2.5Y. Pour les mesures de blancheur, this practice is limited to samples with Munsell values greater than 8.3 (CIEY supérieur à 65) and Munsell chromaticity no greater than 0.5 (Tonalité B) and Munsell chromaticity no greater than 0.5 (Ton Y 0.8) et tous les autres tons de 0.3 (voir 3.3.1).
5.3 The combination of measurement and calculation that results in a yellow or white index is a psychophysical process, C'est, the specified procedure is designed to provide numbers relevant to visual estimates made under specific typical observation conditions. Since visual observation conditions vary widely, users should compare the calculated index with visual estimates to ensure applicability. Some standards that address color and chromatic aberration vision estimation are Practices D1535, D1729, E1360, and E1541, as well as guidelines E1499.
5.4 This practice does not include specimen preparation, a procedure that can have a significant impact on the amount measured. Typiquement, samples should be prepared and presented for measurement in a standard manner for the tests performed. Select enough samples or sample areas to provide average results representative of each sample under test. See Practice E1345.
Calculation of Yellowness Index and Whiteness Index Using Instrumental Color Coordinates
gamme
1.1 This practice provides numbers associated with visual ratings of yellow or white for color specimens of white and near-white or colorless objects, viewed in daylight by observers with normal color vision. Textiles blancs, paints and plastics are some of the materials that can be described by the yellow or whiteness index calculated in this way.
1.2 In order to perform a complete analysis of object color by a specified observer and a specified light source, trois paramètres doivent être utilisés. Cependant, for near-white specimens, il est souvent utile de calculer une échelle singulière de jaunissement ou de blancheur. This practice provides recommended equations for this scale and discusses their derivation and use, as well as the limits of their applicability (see also References (1) 2).
1.3 Values expressed in SI units shall be treated as standard values. Aucune autre unité de mesure n'est incluse dans cette norme.
Calculation of Yellowness Index and Whiteness Index Using Instrumental Color Coordinates
1.4 Cette norme n'est pas destinée à répondre à tous, si seulement, problèmes de sécurité associés à son utilisation. Il est de la responsabilité des utilisateurs de cette norme d'établir des mesures de sécurité appropriées., pratiques sanitaires et environnementales et pour déterminer l’applicabilité des restrictions réglementaires avant utilisation.
1.5 Cette norme internationale est basée sur les principes de normalisation internationalement reconnus établis dans la Décision sur les principes pour l'élaboration de normes internationales., Lignes directrices et recommandations émises par le Comité des obstacles techniques au commerce de l'OMC.