In this research experiments were conducted to investigate the effect of photochromic masterbatches on undrawn monofilament polypropylene yarn and the resultant plain woven fabrics. Two types of photochromic masterbatches, with ability to change color to yellow and blue under the influence of ultraviolet radiation were employed. Plain woven fabric samples were produced using the monofilament yarns as weft threads. Color change experiments were conducted, using a portable reflection spectrophotometer under the influence of D65, D65+UV, UV and Sun light rays. The results showed that, the lightness (L*) due to the addition of the two masterbatches in the yarn samples is almost identical. The existence of polyester-viscose yarns as warp threads in the fabric samples resulted in an increase in the lightness of the fabrics. Under the influence of all light sources, amount of yellow-blueness (b*) in the yarn samples containing yellow and blue masterbatches was found to be negative and positive respectively. With the exception of sun light, similar color change was also observed with the fabric samples. Thus, as expected samples produced using yellow and blue masterbatches tend to be yellow and blue respectively. It was also found that variation in the value of yellow-blueness (b*) of the yarn samples tends to follow a regular increasing pattern.In case of yarn containing yellow masterbatche, sampeles tend to have a deeper yellow color shade due to an increase in the amount of corresponding masterbach. In the case of yarns containing blue masterbatch, increasing the amount of masterbatch result in a deeper blue shade. In the yarn samples containing yellow masterbatche, it was found that, under the influence of UV, D65+UV and Sun light rays, the value of ?E*(a measure to difference in color) tends to increase as the content of the masterbatch.For yarns containing blue masterbatch ?E* increased with increasing amount of masterbatche only under the influence of UV and UV+D65 light sources.It mast be pointed out that in the case of fabric samples, the value of ?E* didnt follow a defined pattern.
