Shampoo, Industry Sector COSMETICS & HYGIENE

SHAMPOO 

 The vast array of hair products available today is enough to make your head spin but they all designed to remove dirt, excess oil and dead skin cells from the scalp and hair

The word shampoo in English usage dates back to 1762, with the meaning "to massage". The word was a loan from Anglo-Indian shampoo, in turn from Hindi champo. A shampoo originally was a hair and scalp massage available at British salons. When the first detergent-based hair product was developed in Germany in the 1890s, the term was then adopted for the hair cleaning product.

During the early stages of shampoo, hair stylists boiled soap in water and added herbs to give the hair health and fragrance. Originally soap and shampoo were very similar products; both were often made from surfactants, a type of detergent. Shampoo became the logical evolution of personal hygiene products, and targeted the specific needs of hair and not the body in general.

In America, the hair care industry would not be what it is today if it weren't for one man's vanity. John Breck started balding at age 25. He gave up his career as a fire-fighter to fight hair loss. In 1908 he opened a scalp treatment centre in Springfield, Massachusetts. In 1930 he introduced a shampoo for normal hair, followed in three years by ones for oily and dry hair. By the end of the 30s he was one of America's leading producers of shampoo.

In 1934 Proctor and Gamble launch Drene the first detergent based shampoo.

Throughout the course of the 20th century a number of specifically designed shampoos were released that gently and effectively cleaned a variety of different hair types. Now, synthetic surfactants are primarily used in shampoo.

WHAT IS HAIR?

Hair is actually dead material when it leaves its root - otherwise it would hurt very much when your hairdresser works with his scissors. On a normal scalp there are about 100-150 thousand hair fibres. A blonde head of hair has usually much more fibres than red or dark haired heads. Hair consists mainly of keratin, which is also responsible for the elasticity of fingernails. A single hair has a thickness of 0.02-0.04mm, so that 20-50 hair fibres next to each other make one millimetre. Hair is strong; it rips after applying a force equivalent to 60kg.

Hair seen through an electron microscope

The root of a hair fibre sticks into a bag in the skin. The fibre is pushed out of this bag about 0.35mm per day, making an average growth rate of 1cm, or half of an inch, per month. The growth rate is however very much related to the individual person, their age, diet etc.

Healthy hair has an average lifetime of 2-6 years. After a rest period of three months the single hair falls out, and a new fibre starts to grow out of the bag.

HOW SHAMPOO WORKS

Shampoos are used to clean hair by stripping sebum from the hair. Sebum is naturally occurring oil that coats the hair and tends to collect dirt and scalp flakes. Surfactants clean hair by stripping sebum from hair shafts therefore removing the dirt attached to it.

Surfactants, also known as wetting agents, lower the surface tension of a liquid, allowing easier spreading, and the interfacial tension between two liquids. The term surfactant is a contraction of "Surface active agent".

In addition to cleansing many shampoos contain Dimethicone, a silicon like substance which coats the hair, filling up tiny holes and giving the hair a smoother feel and a shinier texture. It seals out moisture, thus preventing frizz and keeps flat-ironed hair straight and curled hair curly. It also protects against mechanical damage from dirt throughout the day. Because it locks out damage-repairing conditioner as well, it's better to avoid shampoos that contain lots of dimethicone if you are going to use a hair conditioner.

SHAMPOO ADDITIVES

Whilst many shampoos may make clinical claims most health authorities do not regard them as a medical product. Manufacturers are free to make all sorts of claims about useless ingredients, such as botanical extracts and purified waters.

Vitamins and pro-vitamins are only helpful if ingested. Since your hair isn't living, it can't make use of vitamins or minerals. Applying them directly to your hair will not cause damage, but may be dulling. Amino acids are useless for your hair for the same reasons as vitamins. Some enzymes, however, can help repair your hair if used in conditioners.

SPECIALISED SHAMPOOS

There are shampoos available specifically for those who have dandruff. Such shampoos contain zinc pyrithione, selenium sulphide etc. These chemicals are fungicides, and reduce dandruff by killing Malassezia furfur. Coal tar and salicylate derivatives are often used as well.

Shampoo for infants is formulated so that it is less irritating to the eyes. Most contain sodium laureth sulphate, the mildest of the sulphate family.

Shampoo for animals (such as for dogs or cats) should be formulated especially for them, as their skin has fewer cell layers than human skin. Cats' skin is 2-3 cell layers thick, while dogs' skin is 3-5 layers. Compare that to human skin, which is 10-15 cell layers thick. This is a clear example of why you should never use baby shampoo on a cat or dog.

Shampoo intended for animals might contain insecticides or other medications for treatment of skin conditions or parasites such as fleas or mange. It is important to note that while most human shampoos are appropriate for animal use, products that contain active ingredients/drugs such as zinc in antidandruff shampoos, are potentially toxic when ingested in large quantities by animals (but not humans) and special care should be taken to avoid use of these products on animals.

Crazy Facts Corner

• In World War II pilots wiped shampoo on the windscreen to prevent frosting at high altitudes.
• Blond hair that has taken on a greenish tone due to swimming pool chemicals responds well if ketchup is rubbed in – but use shampoo afterwards!
• Hair care and booze seem to go well together. Washing with beer gives added volume and a splash of vodka apparently removes most product build up.
• Never short on imagination the shampoo manufactures have now started launching shampoo bars. If it does nothing else it will bring back nostalgic memories to the generation that used to rub soap on their hair. 

Links:

http://en.wikipedia.org/wiki/Shampoo

http://www.everything2.com/index.pl?node=shampoo

http://www.geocities.com/HotSprings/4266/chem.html

 http://www.pg.com.eg/history2.cfm

Researched by Dynamic Dave