Patent ID: 7674515

Claim:
An article comprising at least one fluorescent film layer, without the addition of hindered amine light stabilizers or UV absorbers or UV light screening layers, the film layer comprising a polymeric matrix comprising poly carbonate ranging from about 90 to about 99.99 weight percent of the polymeric matrix; and a blend of fluorescent dyes comprising about 0.01% to about 1.5% by weight, based on the weight of the polymeric matrix, of at least one benzoxanthene dye and about 0.01% to about 1.5% by weight of at least one benzothiazine dye, wherein the article has selected fluorescent coloration, wherein the selected fluorescent coloration is fluorescent yellow-green having “x” and “y” chromaticity coordinates bounded by the following coordinates: (x=0.387, y=0.610), (x=0.460, y=0.540), (x=0.421, y=0.486), and (x=0.368, y=0.539) and wherein the article exhibits enhanced retention of fluorescent coloration upon exposure to weathering.