Many types of additives are used in soap manufacturing. Anti oxidant additives, like EDTA, are added to the soap to avoid rancidity due to the oxidation of the fatty acids. Glycerine is added as a skin conditioning additive. Foaming agents are used to facilitate the formation of foam. Antibacterial soap includes some special additives like triclosan. Sulphur is added as anti-acne additive. Titanium dioxide is a whitening and opacifying agent; it helps to increase the opaqueness, and reduce the transparency of the soap bars. Different types of additives are used to produce whitening soap.
There are many other additives used in soap manufacturing, each of which has the proper scope.