ISO 5631-3:2014 pdf free

ISO 5631-3:2014 pdf free.Paper and board – Determination of colour by diffuse reflectance
Reflectometer, having the geometric, spectral, and photometric characteristics described in ISO 2469, and calibrated in accordance with the provisions of ISO 2469.
If materials containing fluorescent whitening agents are to be measured, the reflectometer shall be equipped with a radiation source having an adequate UV-content control, adjusted to a UV condition corresponding to the C iluminant by the use of a reference standard, as described in ISO 2470-1.
Filter reflectometer, a set of filters that, in conjunction with the optical characteristics of the basic instrument, give overall responses equivalent to the CIE tristimulus values X, Y, and Z of the CIE 1931 standard colourimetric system of the test piece evaluated for the CIE standard illuminant D50.
In the case of a filter reflectometer, the radiation falling upon the test piece shall have a UV content corresponding to that of the CIE iluminant C.
Abridged spectrophotometer, the instrument shall have a function that permits calculation of the CIE tristimulus values X, Y, and Z of the CIE 1931 standard colourimetric system of the test piece evaluated for the CIE standard iluminant D50, using the weighting functions given in Annex A.
In the case of an abridged spectrophotometer, the instrument shall have an adjustable filter with a cut-off wavelength of 395 nm or some other equivalent system, and this filter shall be adjusted or the system shall be calibrated with the help of the fluorescent reference standard (5.2.2), so that the UV content of the illumination falling upon the sample corresponds to that of the CIE illuminant C.
Reference standards, for calibration of the instrument and the working standards, used frequently enough to ensure satisfactory calibration and UV adjustment.
Non-fluorescent reference standard, for photometric calibration, issued by an authorized laboratory in accordance with the provisions of ISO 2469.
Fluorescent reference standard, for use in adjusting the UV content of the radiation incident upon the sample, having an ISO brightness value assigned by an authorized laboratory, as prescribed in ISO 2470-1.
Working standards, calibrated frequently enough to ensure that satisfactory calibration is maintained.ISO 5631-3 pdf download.