Chemistry of Cosmetics
Chemistry of cosmetics
Few people would whip out a chemistry set, uncork the vials, and slap the compounds on their face. Yet, millions of women and girls essentially do that every day when they unzip their makeup bags and apply lipstick, mascara, and other makeup. Like the compounds in a chemistry set, makeup consists of chemicals. Although the chemicals in cosmetic products are intended to improve the appearance of skin, lips, and lashes, some can cause adverse effects.
Emulsions
The majority of creams and lotions are emulsions.
An emulsion can be defined simply as two immiscible fluids in which one liquid is dispersed as fine droplets in the other. Homogenized milk is an example of a typical oil-in-water (o/w) emulsion. Milk fat (oil) is dispersed in water as fine droplets by the homogenization process. The reason the fat does not float to the top immediately is due to the presence of emulsifiers; in this case, a milk protein called sodium caseinate as well as several phopholipids. In the case of water-in-oil (w/o) emulsions, water is dispersed as droplets and suspended in the oil phase. The nondispersed liquid or external suspending phase is also called the continuous phase. Mayonnaise, vinegar water dispersed as fine droplets in a continuous phase of soybean oil, is an example of a water-in-oil emulsion. Lecithin from eggs stabilizes the mayonnaise emulsion.
Moisturizers
The main distinction between moisturizers and emollients is their solubility in water. Healthy skin requires moisture. Moisturizers are generally polar materials that are hygroscopic in nature; they hold onto water. An important tool to assess the efficiency of moisturizers is the high scope. It measures transepidermalwater loss or TEWL. After a moisturizer is applied to the skin, the moisture level is recorded. After several minutes the moisture level will be reduced due to the natural tendency of the skin to release moisture over time. Ingredients that can maintain a high level of
Few people would whip out a chemistry set, uncork the vials, and slap the compounds on their face. Yet, millions of women and girls essentially do that every day when they unzip their makeup bags and apply lipstick, mascara, and other makeup. Like the compounds in a chemistry set, makeup consists of chemicals. Although the chemicals in cosmetic products are intended to improve the appearance of skin, lips, and lashes, some can cause adverse effects.
Emulsions
The majority of creams and lotions are emulsions.
An emulsion can be defined simply as two immiscible fluids in which one liquid is dispersed as fine droplets in the other. Homogenized milk is an example of a typical oil-in-water (o/w) emulsion. Milk fat (oil) is dispersed in water as fine droplets by the homogenization process. The reason the fat does not float to the top immediately is due to the presence of emulsifiers; in this case, a milk protein called sodium caseinate as well as several phopholipids. In the case of water-in-oil (w/o) emulsions, water is dispersed as droplets and suspended in the oil phase. The nondispersed liquid or external suspending phase is also called the continuous phase. Mayonnaise, vinegar water dispersed as fine droplets in a continuous phase of soybean oil, is an example of a water-in-oil emulsion. Lecithin from eggs stabilizes the mayonnaise emulsion.
Moisturizers
The main distinction between moisturizers and emollients is their solubility in water. Healthy skin requires moisture. Moisturizers are generally polar materials that are hygroscopic in nature; they hold onto water. An important tool to assess the efficiency of moisturizers is the high scope. It measures transepidermalwater loss or TEWL. After a moisturizer is applied to the skin, the moisture level is recorded. After several minutes the moisture level will be reduced due to the natural tendency of the skin to release moisture over time. Ingredients that can maintain a high level of