Patent ID: 8097668
Filing Date: 2012-01-17
Classification: C08K,G01J

Abstract:
1. A colorimetric composition comprising: a polymeric resin; a dye selected from the group consisting of azo dyes and carbonyl-containing dyes; and a thiopropionate; wherein when the dye is an azo dye, the azo dye is selected from C.I. Solvent Red 23; C.I. Solvent Red 24; C.I. Solvent Yellow 56; C.I. Solvent Yellow 14; or C.I. Solvent Yellow 16, wherein when the dye is a carbonyl-containing dye, the carbonyl-containing dye is selected from C.I. Solvent Orange 60, C.I. Solvent Red 135, C.I. Solvent Red 179, or C.I. Solvent Yellow 104; wherein the colorimetric composition is a blend of the polymeric resin, dye, and the thiopropionate; and wherein the polymeric resin is transparent and wherein a 0.125 inch thick plaque of the composition is capable of shifting from transparent to a dark color as measured using CIELab, wherein the dL* of the dark color is from −1.0 to −20.0 after 1,000 hours exposure according to ASTMG26.