ISO 5631-2:2022 PDF

Scope: This document specifies a method for measuring the colour of paper and board by the diffuse reflectance method with the elimination of specular gloss. It can be used to determine the colour of papers or boards that contain fluorescent whitening agents, provided the UV content of the illumination on the test piece has been previously adjusted to give the calibrated colorimetric value corresponding to CIE standard illuminant D65, using a fluorescent reference standard with an assigned CIE whiteness (D65/10°) value provided by an authorized laboratory, as described in ISO 11475. This document is not applicable to coloured papers or boards that incorporate fluorescent dyes or pigments.

ISO 5631-2:2022 Referenced Document

ISO 11475:2017 Paper and board - Determination of CIE whiteness, D65/10 degrees (outdoor daylight)
ISO 186 Paper and board - Sampling to determine average quality
ISO 2469 Paper, board and pulps*， 2024-03-01 Update

2022 ISO 5631-2:2022 Paper and board — Determination of colour by diffuse reflectance — Part 2: Outdoor daylight conditions (D65/10°)
2015 ISO 5631-2:2015 Paper and board - Determination of colour by diffuse reflectance - Part 2: Outdoor daylight conditions (D65/10 degrees)
2014 ISO 5631-2:2014 Paper and board - Determination of colour by diffuse reflectance - Part 2: Outdoor daylight conditions (D65/10 degrees)
2008 ISO 5631-2:2008 Paper and board - Determination of colour by diffuse reflectance - Part 2: Outdoor daylight conditions (D65/10 degrees)