ORIENTAL LACQUERS .9. POLYMERIZABLE ULTRAVIOLET STABILIZERS FOR ORIENTAL LACQUERS

This paper describes interesting results based on the preparation and utilization of UV stabilizers for Urushi. Ultraviolet stabilizers suitable for protecting coatings of oriental lacquers against the damaging effects of UV radiation were synthesized. 2-(2-Hydroxy-3-tertiary-butyl-5-[3'-hydroxypropyl]phenyl)-2H-benzotriazole (Bzt) was esterified with three unsaturated carboxylic acids: oleic,linoleic, and linolenic acid. The benzotriazole derivatives were characterized by their molecular weight (K+IDS mass spectrum), by their UV spectra and by their gas chromatographic behavior. The compounds were added to three types of oriental lacquer and the compositions were cured. The curing consists of the copolymerization of the active urushi compound, mostly trienes, with the polymerizable UV stabilizers. Simulated testing of the coatings of cured oriental lacquer containing these polymerizable UV stabilizers by exposing the coatings to intensive white light showed that the UV stabilizer containing coatings were several fold more stable than unstabilized urushi coatings.