abstract |
Adhesive compositions are rendered stable against degradation caused by ultraviolet light through the incorporation of selected highly soluble, red-shifted, photostable benzotriazole UV absorbers which absorb light strongly in the 350 to 400 nm range. Also suitable are 2-(2-hydroxy-3- alpha -cumyl-5-tert-octylphenyl)-2H-benzotriazole and 2-(2-hydroxy-3- alpha -cumyl-5-tert-butylphenyl)-2H-benzotriazole in combination with the red shifted benzotriazoles. A further subject of the invention are novel asymmetrical bisbenzotriazoles of formula (IIIc) where G2' is perfluoroalkyl of 1 to 12 carbon atoms, preferably CF3, and where G2 does not contain said group are red-shifted and due to the asymmetry are particularly soluble and useful in a host of applications including automotive coatings, thermoplastics and especially in adhesive compositions, themselves useful in solar panels and other laminate structures. All these UV absorbers exhibit excellent photostability and are highly soluble in adhesive formulations. The laminated articles derived from these compositions include, for example, solar control films, films and glazings, UV absorbing glasses and glass coatings, windscreens, retroreflective sheetings and signs, solar reflectors, optical films and the like. |