PAPER - DETERMINATION OF TRANMITTANCE BY DIFFUSE REFLECTANCE MEASUREMENT (ISO 22891:2007, IDT)
This Malaysian Standard specifies a method for the calculation of transmittance based upon diffuse reflectance measurements.
The use of the method is restricted to white and near-white translucent papers (see 3.9). If it is necessary to determine the transmittance of papers which contain fluorescent whitening agents, the fluorescence emission is eliminated using the prescribed UV cut-off filter.
NOTE This means that, although this Malaysian Standard refers to ISO 2469 which permits the use of both filter colorimeters and abridged spectrophotometers, a filter colorimeter with no means of eliminating the emission of fluorescence is not suitable for this type of measurement if fluorescent whitening agents are present.