Use soaps already existed in the time of the Egyptians, and
Romans who used mixtures of water, ash from plants or animals and animal or
vegetable oils. It was not until the ninth century that laid the soap said
Marseille from animal bones containing potash, herbs and olive oil.
During World War II, was born the "syndet"
(synthetic detergent). They are pharmacists US Navy for marine aircraft
carriers of the US Navy isolated against Japan and sentenced to conserve
drinking water, have sought a substitute for soap. The syndet is obtained with
synthetic surfactants, foam it in fresh water and sea water.
The toilet is designed to eliminate waste on the surface of
the skin to prevent infection and eliminate unpleasant odors.
ON THE SKIN SURFACE, WE
FIND:
-
The sweating products (inorganic and
organic salts ...)
-
Sebum (fatty acids, waxes ...)
-
Cellular waste (fat, protein),
-
Dust, - bacteria and germs
(Staphylococcus, Corynebacterium, Pytirosporum),
-
Possibly cosmetic care or makeup.
TOILET MUST BE ABLE
TO ELIMINATE:
-
Water soluble substances (waste
sweating),
-
Lipo-soluble substances (sebum, cell
debris, most cosmetics),
-
The dust and bacteria mainly by its
mechanical action.
Water can not only meet these requirements. To be
effective, it must be combined with surface-active substances.
Recall that the surfactants are amphiphilic, absorb the
interfaces (lower the surface tension) and give micelles (surround greasy
elements that water can then be removed because they become water soluble). It
follows five properties: wetting, dispersing, emulsifying, foaming detergent.
THERE ARE FOUR TYPES
OF TOILET PREPARATIONS:
-
The soap
-
The syndets
-
Toilet milks,
-
Gels or foaming creams (skin
conditioners).
The last three are from the same family, they are
formulated from mixture of surfactants.
THERE ARE FOUR
FAMILIES OF SURFACTANTS:
-
Anionic surfactants (soaps, sulfates),
detergents good, good foam, irritating,
-
Cationic surfactants (quaternary
ammonium salts) means detergents, foaming means, sometimes irritating,
bactericidal and fungicidal,
-
Surfactants non- ionic (glycol ester,
PEC) means detergents, bad foaming, well tolerated, excellent emulsifying and
dispersing,
-
Amphoteric surfactants (betaine ...)
means detergents, foaming means, very well tolerated.
THE SOAPS
They are obtained after a saponification reaction, that is
to say, the hydrolysis of one or more fat (anionic surfactants) in alkaline
medium. Further steps are needed to achieve the soap as we use it:
-
Elimination of glycerine and impurities,
-
Removal of water by evaporation,
-
Mechanical work to get to its final
form.
We can add perfumes or deodorants, dyes, antiseptics and
Super-fatting (<5%) such as sweet almond oil, olive oil or evening primrose.
Quality soap depends on the choice of raw materials.
Advantages:
-
Good detergents, foaming good, good
emulsifying, cheap
Disadvantages:
-
Soap effect: release of their base on
contact with water, the pH of about 10 solution, changing the physiological pH
of the skin irritant effect
-
Too much detergent, removing the surface
hydrolipidic film (drying)
-
Precipitation of calcium salts (hard
water) resulting in deposits on the enamel bathtubs and skin and prevents its
use on dull hair.
THE SYNDETS
Also known as "soap without soap," They are made
from synthetic active surfactants. In general, these are mixtures of anionic
surfactants useful for their good detergent and amphoteric surfactants whose
tolerance is excellent. We can add:
-
Plasticizers (20-30%) that allow the
solid standard presentation "soap", castor oil, polyol ester, fatty
alcohol,
-
Neutral fillers or extenders (20-50%)
which reduce the concentration of surface -Assets, starch, titanium oxide,
polymer - foam stabilizers, coconut amide,
-
Preservatives and water (8-10%), -
cosmetic adjuvants, antiseptics, super-fatting, sulfur, salicylic acid, weak
organic acids (lactic or tartaric acid) to restore an acid pH of from 4 to 6.
Advantages:
-
Respect the skin pH,
-
Good detergency,
-
Respect of surface hydrolipidic film
-
No precipitation of calcium salts, can
use on the scalp.
Disadvantages:
-
Sometimes low foaming,
-
More than the soap.
THE CLEANSING MILK
These are emulsions in general O / W low viscosity
containing RT in sufficient quantity to emulsify the dirt displayed on the
surface of the skin.
The fatty phase causes the fat-soluble impurities (liquid
petroleum jelly, perhydrosqualene, vegetable oils). The aqueous phase leads to
the water-soluble impurities (aromatic purified water or distilled water).
Surfactants maintain impurities in suspension. They are generally non-ionic. In
their composition also fall preservatives and fragrances.
Qualities required for milk are:
-
Appearance, odor,
-
Ease of spreading,
-
Ease of removal of the hydrophilic and
lipophilic particles
-
pH adapted to skin pH,
-
Low detergency,
-
Respect the hydrolipidic film
-
Lipid phase adapted to the skin type.
Advantages:
-
Gentle cleansing,
-
Respect the skin pH,
-
Met surface film.
Disadvantages:
-
Need a toilet in two stages and a second
product, tonic or astringent
-
Sometimes difficult elimination
-
Low detergency,
-
Sometimes high price.
THE SKIN SHAMPOOINS
Foaming cleansing gels called "liquid bread",
creams, foams, emulsions cleaning. These are associations of synthetic
surfactants, in fact syndet.
CONCLUSION
Clean skin is a balancing act that eliminates the screen
dirt made each day by the environment, makeup and secretions. This screen slows
the natural desquamation, thereby promotes bacterial overgrowth.
Maintain the physiological balance is a fundamental rule
regardless of the type of toilet selected.
The toilet must:
-
Keep the skin pH (4.5 to 5.5)
-
Respect the surface hydrolipidic film
that maintains skin hydration. There is an ecology area to be respected. It is
a guarantee of health and beauty of the skin. The cosmetologist must have as
the main concern of protecting it.
Source: nouvelles-esthetiques
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