Products
Shellac is available as a pure substance in specialized shops. It is included in many medicinal products as an excipient.
Structure and properties
Shellac is a purified product made from the resinous secretions of female specimens of the lacquer scale insect. Depending on the process, four types can be distinguished:
- Waxy shellac
- Bleached shellac
- Wax-free shellac
- Bleached wax-free shellac
Waxy and wax-free shellac is present as brownish orange or yellow, shiny, transparent, hard or brittle, more or less thin scales. Bleached shellac and bleached wax-free shellac are creamy white to brownish yellow powders. All grades are practically insoluble in water, but dissolve in ethanol depending on the type.
Areas of application
- As a coating agent for the production of tablets and coated tablets, for example for enteric-coated tablets and tablets with an altered release of active ingredient.
- For labeling tablets and capsules, often together with indigocarmine or with iron oxides (printing ink).
- As a food additive (E 904).
As an animal product, shellac is unsuitable for vegans.
