Preparation of Artificial Urushi via an Environmentally Benign Process

"Artifical urushi" has been developed by laccase-catalyzed curing of new urushiol analogues. The analogues were designed and conveniently synthesized by regioselective acylation of phenol derivatives having a primary alcohol with unsaturated fatty acids using lipase as catalyst. The curing of the catechol derivative having a linolenoyl group proseeded in the presence of acetone powder from Chinese urusi, yielding the crosslinked film("artificial urushi")with high hardness and gloss surface, thich are compareble with those of natural urushi coating. The analogues obtained from vanillyl alcohol were also cured.FT-IR monitoring of the curing showed that the crosslonking mechanism was similar to that of the natual urushi. The curing of the urushiol analogues in the presence of stach-urea phosphate took place to give the artificial urushi coating exclusively of synthetic compounds.