The measurement of the colour of a tile should be made according to the Standard UNI EN ISO 10545-16, which involves the use of a reflectance spectrophotometer equipped with integrating sphere. Being a measure, it is not subjective as the visual comparison, which is deeply influenced by the operator who performs it. Moreover it can be carried out by choosing different standardized illuminating agents, always in repeatable conditions.
The instrument provides the colour coordinates according to international Standard CIE Lab, the colour differences, the whiteness (CIE, E313, Berger, Hunter, Stensby) and yellow (1925 E313) degrees and the DE and DE_CMC values. It is portable, and can therefore be used even if it is not possible to move the sample (e.g. controversies about tiling in buildings).

Technical features of the instrument

The instrument is a reflectance spectrophotometer mod. Mercury 2000, Datacolor (CH) equipped with both integrating diffuse d/8° sphere, according to ISO and DIN Standards, and a device excluding specularity
The light source is a xenon lamp.

Services to industry

• Measurements according to ISO 10545-16:2010:
  • colour coordinates L, a, b
  • colour differences: DL_ab, DC_ab, DH_ab, DE_CMC
• Measurements according to ASTM C609-07 and BS 8300:2009:
  • LRV (Light Reflectance Value)
  • colour differences: DL_ab, Da and Db
• colour homogeneity of a mix
• dosage of a pigment by correlation between colour intensity and pigment content
• determination of the whiteness degree, typically used for tableware or kaolins.