ICAR Research Data Repository for Knowledge Management

This dataset provides calculated values of the light dose causing a just-noticeable difference (JND) in colour as a function of prior light exposure for approximately 100 dyed textiles. It quantifies the lightfastness of residual colours that remain after damage caused by past illumination. The analysis uses a published dataset [1] of colour measurements versus light dose for historic textiles dyed with early synthetic colourants during the period of 1874–1905.

Detailed information regarding the samples and their sources can be found by cross-referencing ID numbers in the attached files with those of the previous study. Note that the classification of dye composition in the source data was based on cross-referencing trade name and manufacturer with the 1st ed. of the Colour Index. The material characterization may be validated or refined with ongoing chemical analyses.

The following files are included in the dataset:

• 01 - Dose to JND vs prior exposure (Test batch 1_Samples 1-27).xlsx


• 02 - Dose to JND vs prior exposure (Test batch 2_Samples 32-58).xlsx


• 03 - Dose to JND vs prior exposure (Test batch 3_Samples 63-89).xlsx


• 04 - Dose to JND vs prior exposure (Test batch 4_Samples 94-120).xlsx


• 05 - Dose to JND vs prior exposure - all data resampled.xlsx


• 06 - Example Calculations.xlsm


• 07 - Blue Wool Ratings - Figure 6.xlsx

Files 1–4 give the calculated light dose causing a JND for the residual colour as a function of prior exposure. Each file represents a selection of samples from one of the four test batches. The fifth file contains a summary of results for all samples, with data resampled at a set of common dose values. This was necessary to generate Figure 6 in the related manuscript.

The sixth file provides examples of how the calculations were performed using a macro-enabled Excel spreadsheet (.xlsm). The document contains VBA code for determining colour difference with the CIEDE2000 (ΔE₀₀ ) method [2-4], and performing linear interpolation [5].

[1] Hagan, Eric, Itxel Castro-Soto, Marianne Breault, and Jennifer Poulin. 2022. Replication Data for: The lightfastness of early synthetic organic dyes. Harvard Dataverse. https://doi.org/10.7910/DVN/JQMYFM .

[2] Sharma G, Wu W, Dalal EN. The CIEDE2000 color-difference formula: implementation notes, supplementary test data, and mathematical observations. Color Res Appl. 2005;30(1):21–30.

[3] brucelindbloom.com. Delta E (CIE 2000) [Internet]. March 24, 2016 [cited July 6, 2022]. Available from: http://www.brucelindbloom.com/index.html?ColorDifferenceCalcHelp.html .

[4] wikipedia.org. Color difference [Internet]. March 24, 2016 [cited July 6, 2022]. Available from: https://en.wikipedia.org/wiki/Color_difference .

[5] wellsr.com. Powerful Excel Linear Interpolation Function with VBA [Internet]. March 24, 2016 [cited July 6, 2022]. Available from: https://wellsr.com/vba/2016/excel/powerful-excel-linear-interpolation-function-vba/ .