Lightfastness of pigmented handmade papers

Abstract

AbstractArtists are making pigmented handmade papers in increasing numbers to be certain that the color of the paper is lightfast. The lightfastness of handmade papers colored with commonly used pigments was tested. Three methods were used: (1) exposure to a measured 1260 MJ/m2 outdoors to the sun under glass; (2) exposure in the laboratory to daylight fluorescent lamps; and (3) exposure in a window monitored by Blue Wools. Burnt umber and the yellow and red iron oxides were lightfast as expected. Excellent, or sufficiently lightfast, were Pigment Yellow 65 and the lightfast form of Pigment Yellow 74, the phthalocyanine blue and green, ultramarine blue, and the Quinacridone reds if used in sufficiem strength. If the Quinacridones were weaker they were classified as Good in lightfastness along with Pigment Yellow 97. Classified as Fair were the higher‐strength form of Pigment Yellow 74 and the naphthol red with AS‐D coupling. Unsatisfactory, or fugitive, were the lithol and toluidine reds, weaker use of the higher‐strength form of Pigment Yellow 74, and an unidentified organic yellow pigment.