Color measurement on warning clothes
The color of high visibility warning clothing needs to be controlled not only during production, but also after washing. To secure the visibility of the people wearing that clothing the color must be in specific limits which are specified in DIN EN 471. The mayor requirements are:
- Physical iluumination: Polschromatic, CIE D65 adjusted
- Illumination for calculation: CIE D65
- Standard observer: 2°
- Measurement geometry: 45°:0°
- Measurement: single layer over black with R<0.04
The 45°:0° geometry spectrophotometer ERX30 is designed to meet these requirements. Because of the fluorescent colors, the physical illumination has to be adjusted to CIE D65 not only in the visible range, but also in the UV area below 400 nm. By measuring UV included and excluded the built-in Xenon flash lamp is adjusted from 330 nm to 730 nm to the CIE D65 standard. A sample holder with a black hole places the textile at the measurement aperture and ensures a reflectance below 0.04. The ESWin Software shows not only the results as luminance factor ß and color coordinates x and y, but it also provides a ranking whether the color is within specification or not. Additionally all results are displayed graphically in a color plot to understand where exactly the color is and which actions have to be taken.