What Are the Uses of Phosphoric Acid in Cosmetics?

Phosphoric acid in cosmetics is used as a skin-conditioning agent in lotions, creams, and other cosmetic products. It is also used as a pH control for many toothpastes. Phosphoric acid's capacity to alter the pH of cosmetics and oral care products makes it an important ingredient in the production of a wide variety of these products. Phosphoric acid is often added to personal care formulations as a buffering or stabilizing agent or as preservative.

Why phosphoric acid is used in cosmetics

1. It is used as a pH control agent in toothpaste and other oral care products.

This is because phosphoric acid, as a mere dibasic acid, has a lower pKa value (2.79) than other pH control agents such as slat and sulfate salts, which have pKa values of around 6. It is mainly because it is less ionized at neutral or slightly acidic pH that gives rise to these properties: a higher buffering capacity (of about 100% of the molar equivalent in water), which helps toothpaste to foam better, a higher solubility in water (about 200 g/l), and an anti-corrosive ability to generate the surface tension of saliva.

2. It is used as a skin conditioning agent in lotions and creams.

A particularly high buffering capacity (of 300%) is present in creams and lotions. It is used as pH control agent in these products due to its ability to change the pH of the chemical system to maintain an appropriate skin pH. In this way, phosphoric acid has been used as a preservative in lotions or creams that do not contain a preservative system, although it is not necessary to add it when the product is already preserved with other types of preservatives. Since its maximum concentration value does not exceed 0.5% for face creams, it does not interfere with the stability of other cosmetic ingredients containing perfume oils and perfume oils, etc. This shows the use of phosphoric acid in cosmetics.

3. It is used as a buffering/stabilizing agent.

This is because the stability of cosmetic products is often related to the acidity level of that product. Therefore, a buffer with a higher pH will have higher stability. This can be important for some types of perfumes and their perfume oils, etc.

What are example of cosmetics products that uses phosphoric acid?

1. Toothpaste

This product is used because of its ability to maintain a long-lasting foam. Phosphoric acid is sprayed on the toothpaste in order to reduce pH back to neutral. Phosphoric acid is used because it has a higher buffering capacity than other types of buffers.

2. Face powder or skin lotion

These products are applied on the face and affected skin areas, respectively, because they are used as emulsion and spray, respectively. Both products are sprayed with phosphoric acid as it does not interfere with the stability of perfumes, cosmetics ingredients in general and perfume oils in particular.

3. Deodorant

This product is used to eliminate undesirable odor. It is sprayed on the arms, legs and armpits as a deodorant lotion. When applied, it also gives a particular odor due to its composition.

4. Sunscreen lotion or powder

Phosphoric acid is used as a sunscreen because it has UV absorbance properties. It is used to reduce the internal pH of the cream or lotion to maintain a relatively high internal pH, thereby protecting against skin damage caused by degradation of fatty acids and other components in skincare products (such as fragrances). This reduces the long-term resistance of sunscreen cream and lotion against water damage through oxidation and other chemical changes.

5. Perfume oil and perfume materials

Phosphoric acid is used as a pH control agent to maintain a stable pH in perfumes, lotions or creams that contain perfume oils and perfume oils, etc. in order to avoid fading of fragrance or an "off" odor to powder or paint products. In addition, phosphoric acid does not cause the discoloration of beautiful powders due to excess production of hydrogen sulfide gas, which usually occurs during the normal use of phosphoric acid as a preservative agent in cosmetics.

The above-mentioned cosmetics products and uses of phosphoric acid in cosmetics are used because of their applications, which are described above. The above-mentioned cosmetic products and methods that contain phosphoric acid as a pH control agent are useful in the production of cosmetics or to manufacture other related products.