HunterLab EasyMatch QC, User Manual

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EasyMatch QC User’s Manual Version 2.1
A-22 Measurement Values
T
700 nm
= measured transmittance value (%) at 700 nm.
EBC Difference is also available, and is defined as follows:
dEBC-10 mm = (EBC-10 mm)
sample
- (EBC-10 mm)
standard.
EP 10-mm and EP 20-mm (ColorQuest II Sphere, ColorQuest XE,
ColorQuest XT, UltraScan PRO, UltraScan XE, and UltraScan VIS only)
EP (European Pharmacopoeia Color) is a visual liquid color index used in the pharmaceutical industry.
It consists of three primary color standard solutions (yellow, red, and blue) that are combined to produce
five standard color solutions: B (brown), BY (brownish-yellow), Y (yellow), GY (greenish-yellow), and
R (red). These standards are then diluted with hydrochloric acid to make 37 reference EP liquid color
standards: 9 Bs, 7 BYs, 7 Ys, 7 GYs, and 7 Rs.
The EP physical standards
A HunterLab spectrophotometer standardized in a transmission mode may be used to instrumentally
determine the closest EP standard to any sample solution read. Samples should be measured using a 10-
mm or 20-mm path length transmission cell, choosing the matching version of the EP index for display.
The EP standard value (or “Water” if the sample is closest to water white) is then reported.
Refer to European Pharmacopoeia Method 2.2.2, “Degree of Coloration of Liquids,” for more
information.
Gardner-20 mm and D6166 (ColorQuest II Sphere, ColorQuest XE,
ColorQuest XT, UltraScan PRO, UltraScan XE, and UltraScan VIS only)
The Gardner indices are designed for transmission measurements of samples, such as resins, that are
darker yellow or browner than those samples that would be measured with the APHA index. Samples
should be measured using a 10-mm path length transmission cell for the D6166 index and a 20-mm cell
for the 20-mm index.
The Gardner-20 mm index is a proprietary yellowness index based upon a correlation between ASTM
YI E313 and Gardner Color.
Gardner-20 mm Difference is also available, and is defined as follows:
dGardner-20 mm = (Gardner-20 mm)
sample
- (Gardner-20 mm)
standard.