Grading textile fastness. Part 4: An inter‐laboratory trial using DigiEye systems†,‡

In Part 1 of this series of papers, a new method for assessing textile fastness using an imaging system based upon a digital camera was introduced. In Parts 2 and 3, all available experimental data were used to develop new fastness formulae for assessing staining and change in colour, respectively. The combination of the digital method and the two formulae markedly outperformed the current ISO formulae. In the present study a further inter-laboratory trial has been conducted under the auspices of TCI/81, Colour Fastness and Colour Measurement Committee. Twelve laboratories and 38 professional assessors took part in this trial. Two Digi-Eye systems were used to measure all the colours. The results provide strong evidence that the newly developed formulae together with the digital imaging method can accurately predict the visual results.