HunterLab’s colour measurement transmission spectrophotometers using USP and EP cells of 10mm and 20mm path length can use the CIELab colour scale to objectively measure both a USP and EP colour standard if available and compare this with a product sample. The measurement of the Colour Standard provides a CIELab value that will remain constant over time, unlike a physical standard.
The USP and EP Colour Standards are liquid visual colour standards intended to improve colour communication between sites by defining a sample colour as being close to a physical liquid standard, e.g. “near USP F” or “near EP Y2” rather than using words such as “light yellow”.
The fact that the colour measurement transmission spectrophotometers use the CIELab colour coordinates allows sites to communicate colour information quickly and with a high degree of accuracy.
HunterLab’s colour measurement transmission spectrophotometers are available from Novasys Group .