Shellac - Wax-Containing Button Lac
Button Lac - Button Pats - Shellac Buttons - Wax-Containing Shellac (Ph.Eur.) - Orange Shellac (USP)
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.
Button Lac is refined from Seedlac using the Heat Melting process, which does not remove the naturally occurring wax contained in the Lac. It is produced using traditional handmade methods, which involves packing Seedlac into a long, narrow, round cloth bag and heating one end over an oven containing a charcoal fire while the other end is gradually twisted. The heat produced by the fire melts the Lac which is forced out through the pores of the cloth by winding pressure. The molten Lac is formed into a flat circular disk around two inches in diameter which is often stamped with the seal of the manufacturer.
Button Lac contains around 5% natural Shellac wax. The colour of the buttons depends on the type of Seedlac used, which relates to the Lac insect strain, the host tree from which it extracts the sap. Typically, they are pale lemon-yellow to brownish-orange. Button Lac generally has a longer shelf life than Shellac flake, so is preferred by customers if they intend to store the Shellac and use it over an extended time period.
When dissolved in an alcohol or aqueous alkaline solution, Button Lac has a milky appearance, 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.
Please click on the following links for more information about how Button Lac is used in the following industries and its applications: