Science and Technology of Shellacs

The commercial form of lac resin, known as shellac, is composed of low molecular weight polyester macromolecules consisting inter- and intra-esters of polyhydroxy aliphatic and sesquiterpene acids. The exceptional qualities of shellac provided widespread and open applications in various fields, especially in the food and pharmaceutical industries, for ages. Earlier, it was used primarily for coatings, furnishing, and wall paintings, electrical insulations, and dental baseplates. But the new world has seen an increasing shift in the applications of shellac due to its adaptability, biocompatibility, structural modification capability, solubility, and thermoplasticity. The shift in the processing techniques from traditional methods accelerated shellac processing which is witnessed in the development and application of shellac-based materials in green electronic components, 3D printing, dental composites, electronic sensors, and desensitizing agents. Not only shellac but the value-added by-products (especially lac dye and lac wax) formed during the processing of lac resin to shellac had economic importance. This chapter provides an insight into the processed form of lac resin, shellac; and its various sources, forms, processing techniques, properties, structural modification, nanofibers of shellacs, and different applications.