Pear Soap is a brand of gentle, glycerin-based soaps first produced by Andrew Pears in London in 1789. It's still used by gardeners for cleanup because it contains only high-quality skin-care ingredients with nothing to create artificial color. The formula of cleaning materials is mild and designed for people who would use it multiple times a day.
Palmitic acid is a fatty acid commonly derived from palm oil. When this liquid is then dried, it forms a crystalline structure known as sodium palmitate. In soap, this chemical works to break up grease and oil on the skin.
Rosin is derived from pine trees. It is a solid resin from which more volatile chemicals have been removed by slow heating. Rosin is a pale green solid at room temperature and melts very easily. In Pear Soap, it is used as both a thickening agent to keep the soap congealed without excessively drying the soap.
Glycerin is a clear, thick, sweet-smelling liquid. It is a humectant: it absorbs moisture to the degree that this moisture is then imparted back into the skin on contact. Glycerin is a byproduct of the soap- and candle-making industries, a material which is obtained by rendering down animal fat.
At the time Pear Soap was invented, glycerin was used for moisturizing lotions rather than soap because more money could be charged for these lotions. Later on, glycerin was in high demand for making dynamite. Even now only a portion of soaps are made with glycerin and are typically considered the highest quality soaps on the market.
Sodium cocoate is produced by combining coconut oil with sodium hydroxide. The result is a solid crystalline salt which is a surfactant, another type of cleansing agent which breaks up the surface tension of water. This helps the soap to lather better and sluice away more cleanly without leaving behind soap residue.
There are two oil extracts in Pear Soap: rosemary and thyme. Aside from imparting a pleasant odor that is not overly sweet or perfumey, these oils have effects on the skin. Rosemary helps strengthen the walls of capillaries in the skin, tightening and toning it. Thyme acts as an emollient. It softens the skin by creating a thin layer across the skin, enhancing its ability to retain moisture.