2. SOAPS
Soaps are sodium or potassium salts of long chain fatty acids. When triglycerides
in fat/oil react with aqueous NAOH or KOH, they are converted into soap and
glycerol. This is called alkaline hydrolysis of esters. Since this reaction leads to the
formation of soap, it is called the saponification process.
3. SYNDETBARS
The word “syndet” is derived from “synthetic” combined with “detergent”.
Technically it refers to the binding that occurs between different detergents, also
called surfactants or tensioactive agents .Syndet soap surfactants are derived from
oils, fats, or petroleum products that are processed in a wide range of chemical
processes other than traditional saponification.
4. RAW MATERIALS
FATS AND OILS-
Fat mixture containing saturated and unsaturated and long and short chain fatty acid in
suitable proportion are used .Saturated fatty acids with 12 to 18 carbon atoms are used .
E.g. Lauric, myristic , palmitic , stearic and oleic acid
In the united states of America and Europe tallow has long been used as a basic
ingredient of soap. To improve the solubility and lathering properties coconut oil is
mixed with tallow.
Fish oils, palm oil and coconut oil are also used in preparation of soaps.
5. ALKALIS
Caustic soda is used as a raw material in the preparation of soap.
Caustic potash is used in making soft soaps
Potassium carbonate and soda ash are used to saponify fatty acids
6. ADDITIVES USED
• Antioxidants: these are used to stabilize the soap against rancidity.
• E.g. Sodium silicate, sodium hyposulphite, sodium thiosulphate.
• Whiteners: titanium dioxide and zinc oxide are used to improve whiteness.
• Perfumes : the PH of the soap is around 10.0. The selected perfume should be stable
in this PH range
8. SOAP MANUFACTURING
1. Cold process
In this process, mixing of fat and strong alkali is carried out substantially at room
temperature so that little more than emulsification takes place . saponification is
completed after this mixture is run into frames in several days at warm
temperature. Since there is no opportunity to adjust proportions of fat and alkali
calculation of quantities to be used should be made carefully.
9. SOAP MANUFACTURING
2. Semi-boiled process
The semi-boiled process differs from the cold process in the fact that the saponification
mixture is heated to 70 - 90° C using a steam-heated coil to accelerate and complete the
saponification reaction. Dyes, perfumes, and additives are added at the end of the
process to prevent them from evaporating. The process allows the quantity of soda
undergoing saponification to be adjusted before the crude soap is drawn off. It also
allows manufacturing waste to be recycled, better incorporation of the additives and a
wider choice of raw materials.
11. SOAP MANUFACTURING
3. Full boiled process
In this process ,large cylindrical kettles with cone bottoms equipped with open and
sometimes with closed coils for steam are used. The kettles are often provided with
delivery pipes for fats , water, lye
Process includes:
• Saponification reaction
• Graining out and washing
• Strong change
• Finishing or fitting operation
13. SOAP MANUFACTURING
4. Continuous saponification
These processes are used when the production is on very large scale .Fats are first
converted into fatty acids and glycerin using high pressure in continuous fat
splitting process.
14. OTHER TYPES OF SOAPS
Transparent soaps
Bathing bar
Castile soap
Super fatted soaps
Carbolic and carbonated soaps
15. SYNDETBARS
Often referred to as "syndet bars" or "soap-free“ soaps, these use synthetic - and
usually milder - surfactants such as sodium cocyl isethionate (which is derived from
coconuts) or sodium palmitate. Since they utilize less alkaline salts in their
surfactants, these have a much lower PH, which makes them less irritating. Dove, the
very first syndet bar introduced in 1955, is made primarily from sodium lauryl
isethionate but contains sodium tallowate and palmitate too.
17. SOAP VS SYNDETBARS
Soap is extremely effective in cleansing the skin. It strips away everything, including
our skin’s natural oils. Soaps are known to be harsh and its use can damage skin
layers that regulate the hydration of our skin.. Soap bars also have a PH ranging from
9 to 10, making it more alkaline in comparison to our skin which has a slightly acidic
PH from 5 to 6.
Syndet bars are mild and cause less damage to our skin. The PH of syndet bars are
usually around 5.5, which is very similar to the natural PH of our skin. These bars are
effective cleansers, cause minimal damage to skin layers, and do not have the harsh
stripping effects of regular soap.
18. REFERENCES
1. Harry’s Cosmeticology, Volume 1 Of 2, 8th Edition, Published By Chemical
Publishing Co. Inc. New York.
2. Poucher’s Perfume Cosmetics And Soaps, 10th Edition.
3. www.Google.Com