Novel Chromatic Technique Based on Optical Absorbance in Characterizing Mineral Hydraulic Oil Degradation

Table 1

Comparison of CR with conventional chromatic parameters—saturation 𝑆, Hue 𝐻, CIE—chromaticity (𝑥-𝑦) coordinates, for fresh (A sample) and in-service degraded (B sample and C sample) oils.

Samples	CR	CIE coordinates		Saturation 𝑆	Hue 𝐻
		𝑥	𝑦
DTE25 oil
Air	0.453	0.195	0.430	0.376	165.9
A sample	0.470	0.280	0.596	0.658	79.9
B sample	1.028	0.471	0.458	0.737	58.04
C sample	1.051	0.476	0.454	0.745	56.55
D sample	1.200	0.507	0.422	0.753	48.39
DTE24 #2 oil
Air	0.453	0.195	0.430	0.376	165.9
A sample	1.012	0.388	0.383	0.257	58.3
B sample	1.159	0.481	0.415	0.644	49.5
C sample	1.171	0.504	0.431	0.771	49.9