CAS Number: 9000-59-3
EINECS Number: 232-549-9
Shellac is a natural resin refined from Lac, the secretion of the tiny red Lac insect, Kerria lacca, which is parasitic on certain host trees in India.
Wax-Containing Shellac is refined from Seedlac using the Heat Melting process, which does not remove the naturally occurring wax contained in the Lac. It is usually machine-made and is extracted from the Seedlac by melting it using steam heat and then squeezing the molten Lac through a fine metal filter using hydraulic presses. The molten Lac is then stretched by stainless steel rollers into a long thin film before being broken into flakes once cooled.
Wax-Containing Shellac is sold in flake form and typically contains around 5% wax. It is soluble in alcohol and aqueous alkaline solutions. The colour of Wax-Containing Shellac depends on the type of Seedlac used, which relates to the Lac insect strain and the host tree from which it extracts the sap. Wax-Containing Shellac is available in a variety of grades that are categorised by colour.
Wax-Containing Shellac has a milky appearance when prepared in alcohol or aqueous alkaline solutions, but dries to a clear finish when applied as a surface coating. Compared to Dewaxed Shellac, it is more viscous and requires fewer applications when used as a coating since it builds up more quickly on porous surfaces. Wax-Containing Shellac is mainly used by industrial users for technical applications.
