Light Fastness of Yellow Tonality Safflower Used in Manuscripts Restoration

To examine the effect of yellow color tonality of safflower based on old Iranian dye making instructions. Color resistance and stability of colored papers against light was tested to identify advantages and disadvantages of the dyeing method. Methodology and Research Design: Instructions for making yellow tonality with safflower were extracted from old Iranian texts. Three samples of the same colored restored paper were colored with safflower and dried. The samples and the control sample were exposed to light in xenon chamber at 45°C temperature and 25% relative humidity, then changes of color were measured with colorimeter and compared with the samples before exposure. Degradation of cellulose in exposure to light with photochemical reactions, the cellulose degradation rate was studied with pH Meter, FTIR. Tensile strength was measured. Findings and Conclusion: Wattman paper showed more stability than the other two samples due to the lack of additives. Also, samples colored in accordance with conventional instructions showed more color change than those colored with old instructions with regard to calorimetric parameters. Destruction of samples colored according to both instructions was negligible. Therefore, the coloring with safflower does not cause serious damages to cellulose fibers.