Development of a fast drying lacquer based on raw lacquer sap

A series of new lacquers, based on the raw lacquer sap that drying fast in the natural environment, has been developed using a repeated-kurome process. Fast drying occurred due to the repeated-kurome process from K-0 to K-4, and the 982 cm(-1) for the dienes decreased and the 993 cm(-1) for the trienes increased in the IR measurement. In addition, the polymerization of urushiol by laccase was revealed for the first time by the repeated-time course of GPC measurements. The results suggest that the molecular weight of urushiol was gradually increased by the repeated-kurome process, and the emulsion micelle in the raw lacquer decreased from 10 to 1 mum in the kurome lacquer. A lacquer based on raw lacquer that dries fast at room termperature and humidity can be obtained by stirring with additional moisture in the reaction vessel, the kurome process, with a decrease of the urushiol monomer. (C) 2004 Elsevier B.V. All rights reserved.