The solution left after removing the soap contains glycerol , which can be recovered by fractional distillation . To improve the quality of soaps desired colours , perfumes and medicinal chemical substances , added .
Types of Soaps
Different kind of soaps are made by using different raw materials .
1 . Toilet soaps These are prepared by using better grade of fat or oil and care is taken to remove excess alkali . Colour and perfumes are added to make these more attractive .
2 . Floating soaps These can be prepared by beating tiny bubbles into the product before it hardens .
3 . Transparent soaps These are made by dissolving the in ethanol and then evaporating the excess solvent .
4 . Medicated soaps Medicated soaps are prepared by some antiseptics like dettol or bithional .
5 . Shaving soaps These contain glycerol to prevent drying . A gum called rosin is added while making them . It forms sodium rosinate which lather well .
6 . Laundry soaps These sodium silicate , borax and contain sodium fillers like carbonate . sodium rosins
7 . Soap Chips These are made by running a thin sheet of melted soap on a cool cylinder and scraping off the soaps in small broken pieces .
8 . Soap grannules These are dried miniature soap bubbles .