Dernatology

1. SOAP
Dr. Nitin Choubey
Dermatology

2. DEFINITION
Soap is the term for a salt of a fatty acid or for a variety
of cleansing and lubricating products produced from
such a substance.

3. Saponification
• Saponification is the name for a chemical reaction between an
acid and a base to form a salt.
• Soaps containing sodium or potassium salts are formed by
heating fat (i.e., glyceryl ester of fatty acid) with aqueous
sodium hydroxide or potassium hydroxide solution. This
reaction is known as saponification.

8. S0AP in making….
• In this reaction, esters of fatty acids are hydrolysed and the
soap obtained remains in colloidal form.
• Only sodium and potassium soaps are soluble in water and are
used for cleaning purposes.
• Generally potassium soaps are soft to the skin than sodium
soaps. These can be prepared by using potassium hydroxide
solution in place of sodium hydroxide.
• Potassium hydroxide is more prominently used for liquid soap
making.

9. Types of soaps with their
uses….
• Basically all soaps are made by boiling fats or oils with suitable
soluble hydroxide. Variations are made by using different raw
materials, making different types of soaps.

10. • Toilet soaps are prepared by using better grades of fats and
oils and care is taken to remove excess alkali. Colour and
perfumes are added to make these more attractive.
• Soaps that float in water are made by beating tiny air bubbles
before their hardening.
• Transparent soaps are made by dissolving the soap in ethanol
and then evaporating the excess solvent.

11. MEDICATED SOAPS
There are many types of medicated soaps that can be helpful
to us such as anti-septic soap that generally helps to relieve
various skin problems, by adding triclosan, bithionol and
Chlorhexidine to them.
Then there are anti fungal soaps having therapeutic effects
that reduce the discomfort and relieve the symptoms caused
by various fungal infections. (Ketoconazole soaps)

12. • One of the very popular types of medicated soaps include the anti
acne soap that help in getting rid from acne and pimples, containing
salicylic acid, glycolic acid or benzoyl peroxide. Cleansers with these
ingredients can penetrate your pores and eliminate pore-clogging
impurities—like dead skin cells, makeup, excess oil and bacteria—
that irritate skin and make acne worse.
• The anti cellulite soap are the medicated soaps for reducing
cellulites that are the dimpled skin( orange peel) in such areas of
body as hips, thighs and buttocks as a result of deposition of fat.
• The anti mosquito soap is used to dispel mosquitoes, mostly in
mosquitoe-infested areas. Contents being citronella oil, eucalyptus
oil, lavender oil, menthol oil, and calendula, that all are proven to
have a scent that the mosquitoes don’t like.

13. • There are certain medicated soaps that not only have
therapeutic effects but are beauty treatments too such as anti
aging soap that are useful for both cleansing the outer body as
well as to slow down the signs of aging.
• There are many other types of medicated soaps like sensitive
skin soap which is gentle to the skin and maintains it properly.
• Anti itch soap is for relieving skin problem of itching.
• Anti chlorine soap is used while swimming to keep the
harmful effects of chlorine at bay.

14. SOAPS IN ACTION
• The dirt (oil and grease) are organic in nature, and insoluble in
water. Hence, it cannot be removed only by washing with
water. When soap is dissolved in water, its hydrophobic ends
attach themselves to the dirt and remove it from the surface.
• Then, the molecules of soap arrange themselves in micelle
formation and trap the dirt at the centre of the cluster. These
micelles remain suspended in water like particles in a colloidal
solution. The various micelles present in water do not come
together to form a precipitate as each micelle repels the
others because of ion-ion repulsion.
• Thus, the dust particles remain trapped in the micelles (which
remain suspended), and are easily rinsed away by water.
Hence, soap micelles remove the dirt by dissolving it in water.

16. • Hard water contains calcium and magnesium ions. These ions
form insoluble calcium and magnesium soaps respectively
when sodium or potassium soaps are dissolved in hard water.
• These insoluble soaps separate as scum in water and are
useless as cleansing agent.
• In fact these are hinderance to good washing, because the
precipitate adheres onto the fibre of the cloth as gummy
mass. Hair washed with hard water looks dull because of this
sticky precipitate.
Why do soaps not work in hard
water?

18. SIDE EFFECTS
 Soap salts are basic or alkaline in nature with a pH value of
about 9-10 while our skin has an acidic nature with a pH
between 5.6 and 5.8. Using soap on your skin increases the pH
of our skin harming it.
• Abnormal Peeling Of Skin
• Dry Skin
• Skin Irritation
• Feeling Warm
• Redness Of Skin
• Stinging Of Skin
• Life Threatening Allergic Reaction

19. THANK YOU