Perm (hairstyle)
The term perm (abbreviation: DW ) is the chemical conversion process, in which straight hair wavy or curly. Colloquially, a hairstyle with permed hair is simply referred to as perm. A perm can be used professionally by a hairdresser at the salon, but there are also products for use at home.
The hair deformation occurs by chemical reaction in the hair keratin. In this case, the cystine bonds in hair keratin, which are responsible for the mechanical strength, disrupted by reduction with thioglycolic acid. The softened hair can be brought into the desired shape by means of curlers. By oxidation with hydrogen peroxide, the disulfide bonds that provide stability, are prepared from the reduced sulfhydryl groups again. The hair will now remain in the prescribed form.
Short-term change in shape
By the action of water, the hydrogen bonds of hair keratin to be solved. The hair becomes malleable and moldable. In " blow-dried styles " brings you wet hair first into the desired shape, and then allowed to evaporate the water. However, the durability of blow-dried styles is low. By setting lotions or hair sprays durability can be increased slightly.
Permanent change in shape
The duration of wave is carried out in two steps. For the first step is a reducing agent, a permanent wave agent, for the second step an oxidizing agent, a fixing agent is required. Sometimes a thorough examination of the hair from the hairdresser must be made in advance. Thin hair can be worse in a perm bring as thick hair.
Advance the hair is washed with a shampoo and treated with a maintenance solution. Then small sections of hair are wound on curlers (up to 60 pieces). The hair is then wetted with the waving agent solution.
Permanent wave preparations are as solutions, gels or aerosol foams commercially. Very often mildly alkaline permanent waving compositions (also neutral and strongly alkaline preparations are known ) are used, they have a pH of 7.5 to 9 - as a pH buffer is ammonium hydrogen - and include six to eleven percent thioglycolic acid. In such a solution, the thioglycolic acid is present as ammonium salt. Also, sulfite, cysteine or cysteine derivatives - such as cysteamine - be used to reduce sometimes. Through the opening of the disulfide bridges, the natural protein structure of the hair is changed ( " denatured " ) and made malleable. The hair shrinks in length slightly swells it in diameter (up to 100 %) and takes the form of the winder to.
A permanent wave composition contains emulsifiers and combability (cationic polymers). Sometimes it is advisable to accelerate by heat ( heat hoods ) the conversion. The exposure of the corrugated medium solution is approximately 10-30 minutes.
The hair is then thoroughly washed with water and thus exempt from the Thioglykollösung. In order to fix this new shaping of the hair, are by means of an oxidizing agent, usually hydrogen peroxide, or oxygen, the disulfide bonds are closed again ( " renatured "). The fixative is applied as a foam or liquid and rinsed after a contact time of 10 minutes with water. The hydrogen peroxide concentration of the fixing agent can be between one to twelve percent, and also it still contains some phosphoric acid so that the pH will lie between 2 to 4. By hydrogen peroxide but also the hair pigment can penetrate and the hair are lightened. Alkaliperoxoborate should not attack the hair pigment.
Furthermore, emulsifiers and combability are included in the fixative.
Finally, the curls can still be treated with a skin care preparation, and then the hair is dried. Failures in perms can occur if the exposure time or the temperature were chosen incorrectly, the curlers were too big or too small or the hair was not rinsed thoroughly enough.
Since curls are under an inward tension, they slowly go through frequent hair washing, by combing and brushing back into the original ungelockte form, since this state is more stable for the hair.
With a so-called counter shaft, the opposite effect is possible: you can so curly or wavy hair smooth, but not at longer times. The chemical agents in this procedure remain the same, but the hair is not wrapped around curlers, but smoothed out.
History
The method of preparing the hot perm was invented in 1906 ( patented in 1910 ) by the German hairdresser Karl Ludwig Nessler ( 1872-1951 ), who lived in the U.S. later. In her soaked strands of hair were on turned up vertically with spiral curlers and heated individually by means of a pair of pliers with borax. On 8 October 1906, the first electrically operated permanent wave apparatus was presented in London.
1924 developed Josef Mayer ( 1881-1952 ) in Karlovy Vary, the so-called flat winding. The first perm chemically produced was introduced by Clark and Speakman in 1932. Sulfite with the disulfide bonds of the hair are split, so that it is deformable. Subsequently, a heat treatment for molding, wherein disulfide bonds are formed again.
In 1940, the thioglycolic acid to reduce the disulfide bonds was discovered in hair keratin. Since 1947, the cold permanent wave or cold wave is common in the keratin of the hair is only chemically softened and reshaped. In the 1970s, the African- look with extremely small curling locks was popular, the hair was not blow-dried, but dried in the air. Since the 1990s, the perm is no longer so much in demand.