Vendors selling bangles are seen in the streets of Kolkata. There are also separate shops which sell a variety of bangles. The cosmetic, cosmetics, cosmetology, makeup or makeup, is the set of treatments, employing natural and synthetic substances, designed to treat and improve the appearance and odor of the human body for the purpose aesthetic. Related primarily to the care of face, skin, nails and hair is widespread in all cultures since ancient times.
The operations of the makeup are very different from each other because of the beauty standard in force. In case of defects, is covering the asymmetries and imperfections as in makeup camouflage, and in the case of the merits will highlight the traits more pleasing.
The oxidation the most common phenomenon of degradation which alters the organoleptic values of the cosmetic, in particular unsaturated lipids. Any substances arrive rancid odor damage and irritate the skin. There is talk of autoxidation when the activation energy comes from the presence of UV rays, heat, moisture, oxygen, metal ions particularly iron and copper.
As long as it is not consumed oxygen, a peroxide radical attacks a fatty acid RH, forming radical R and hydroperoxide unstable that degrades into free radicals, aldehydes, ketones, alcohols and volatile responsible for the bad smell that highlights the rancidity occurred. For these reasons it is recommended to be stored in cool and dry places.