Color switching transparent materials based on vinylidene-naphthofurans

Vinylidene-naphthofurans were dispersed in poly(methyl methacrylate) and Kurarity copolymer affording solid uncolored and transparent materials that show thermally reversible photochromic properties when exposed to the UV light. The composition of the material was optimized to maximize the color intensity under UV and the fading kinetic in the dark. An uncolored Kurarity material doped with 1-(2,2-diphenylvinylidene)-2,2-diphenylnaphthofuran, chloroacetic acid, decanediol, and PEG-400 develops an intense violet coloration upon exposure to the UV light for 2 min and loses 95% of the coloration after 5 min in the dark, at room temperature.