Shellac, with the CAS number 9000-59-3, is a natural resin secreted by the female lac insect, Kerria lacca, on trees in certain regions of India and other countries1. It is known for its unique properties, such as biocompatibility, non-toxicity, and excellent film-forming and adhesive characteristics2. Shellac is used in a variety of applications, including food preservation, pharmaceuticals, electronics, and as a coating for wood and other materials2. It is also used as a crucial carbon source for graphene materials2.
The resin is available in different forms, such as flakes, powder, and bleached versions, each with specific uses. For instance, bleached shellac is often used in the cosmetic industry for products like mascara and nail polish, while wax-containing grades are used in confectionery to prevent sticking and improve appearance4. Shellac is also used in the pharmaceutical industry for coating tablets and pellets, providing a moisture barrier and enteric coating to ensure drug stability and controlled release4.
In terms of chemical properties, shellac is insoluble in water but soluble in alkaline solutions and certain organic solvents like ethanol4. It has a melting point of 115-120°C and is stable under normal conditions, but it is incompatible with strong oxidizing agents.
Overall, shellac is a versatile natural material with a wide range of applications, from traditional uses in coatings and varnishes to modern applications in pharmaceuticals and electronics. Its unique combination of properties makes it an important substance in various industries.
