Abstract
The effect of the light sources for art galleries and museums on fade-prevention of fabrics containing natural dyes was investigated. 11 fabrics dyed with four kinds of main colorants and five kinds of mordants, which are often used in textile properties and the Blue Scale were used as test samples. The light sources were the fluorescent lamp type D65 daylight illuminant simulator, the conventional cool white fluorescent lamp for general illumination, and the fluorescent lamp for art galleries and museums, which is designed to reduce fading by cutting the ultraviolet radiation. Under controlled temperature (29±1°C) and relative humidity (59±2 %), exposure was continued for 700 hours. Then the color difference (ΔE) of each sample was calculated.
Discoloration of the Blue Scale was recognized for the scale less than 3rd grade for all the lamps, but ΔE did not exceed 2. Comparing the grade of the discoloration of the dyed fabrics with that of the Blue Scale, curcumin/iron (III) acetate, quercetin, heamatoxylin, and carminic acid were equivalent to the 2nd grade, and curcumin/hydrated lime, alumstone, and ash were equivalent to the 1st grade for each lamp. From the comparison of ΔE of the dyed fabrics between the lamps, the average effect on fade-prevention for lamp for art galleries and museums was 28% compared with lamp type D65, and 30% compared with the white lamp. The maximum fade-prevention effect was 50% for curcumin/iron (III) acetate.
