Does glycerin make the skin darker?

More and more people think that glycerin is just a chemical substance, a blending agent, and there is no need to use it on the body. If used carelessly, it may cause great harm to the body. In fact, the weather is getting colder and the winter is dry, so at this time everyone needs to know some care methods about glycerin. The most common question is whether using glycerin on the skin will cause the skin to darken?

The details are as follows:

1. Glycerin is propylene glycol. It is the simplest trihydroxy alcohol. Molecular formula HOCH2CH(OH)CH2OH. Also known as propylene glycol.

In nature, glycerol is mainly present in the form of glycerides in animals and plants. A small amount of glycerol is found in palm oil and very few other oils. Colorless viscous liquid. Has a sweet taste. Melting point 20℃, boiling point 290℃ (decomposition), relative density 1.2613 (20/4℃).

Pure glycerol can form a crystalline solid, which is most likely to crystallize when cooled to -15 to -55°C. It has strong water absorption and is miscible with water. It is also soluble in acetone, trichloroethylene, and ether-alcohol mixtures.

Glycerol is similar to monohydric alcohols. For example, it reacts with metallic sodium to form sodium monohydric glycerol alcohol. It reacts with dry hydrogen chloride gas to produce 2,3-dihydroxy-1-chloropropane and 1,3-dihydroxy-2-chloropropane.

It reacts with hydrogen chloride in ether solution to mainly produce 2-hydroxy-1,3-dichloropropane. When oxidized, it produces glyceraldehyde and glyceric acid; when reduced, it produces propylene glycol. Glycerol reacts with a mixture of sulfuric acid and nitric acid at around 10°C to produce glycerol trinitrate, commonly known as nitroglycerin. This compound decomposes into a large amount of gas, water vapor and carbon dioxide after a slight collision, causing an explosion.

Nitroglycerin is also commonly used as a cardiotonic and anti-anginal drug. Fatty acid chlorides or anhydrides can esterify glycerol. Glycerin reacts with hydrogen peroxide, peracid, ferrous salt, dilute nitric acid, etc. to generate glyceraldehyde and dihydroxyacetone; it reacts with concentrated nitric acid to generate glyceric acid.

Glycerol can also be oxidized by lead tetraacetate or periodic acid. When glycerol is heated with potassium sulfate or concentrated sulfuric acid, intramolecular water loss occurs to generate acrolein.

Glycerin is a by-product of the soap industry and can also be made by fermenting molasses with special yeasts. Glycerol can also be synthesized using propylene as raw material. Glycerol is widely used as a chemical raw material for the manufacture of synthetic resins, plastics, paints, nitroglycerin, oils and beeswax, etc. It is also used in the pharmaceutical, fragrance, cosmetics, sanitary products and other industries.

Second, the role.

Glycerin is the most common moisturizer and is very cheap. It is found in almost all skin care products.

Glycerin can absorb moisture from the air to moisturize the skin, and it can also lock the moisture in the skin and prevent it from being lost.

3. Usage:

1. Dilute with plenty of water and apply to the skin with a cotton pad to moisturize. (Glycerin: water is 1:20)

2. After dissolving in water, it can be added to creams and lotions to enhance moisturizing properties.