1. Moisturizing effect
Moisturizing effect is the most important role of sodium hyaluronate in cosmetics. Compared with other moisturizers, the relative humidity of the surrounding environment has less influence on its moisturizing properties. Commonly used humectants in cosmetics include glycerin, propylene glycol, sorbitol, polyethylene glycol, sodium lactate, sodium pyrrolidone carboxylate and so on. Experiments show that, compared with these humectants, sodium hyaluronate has the highest moisture absorption under low relative humidity (33%), and the lowest moisture absorption under high relative humidity (75%). This unique property is adapting to the skin's requirements for the moisturizing effect of cosmetics in different seasons and different environmental humidity, such as dry winter and humid summer. The moisturizing properties of sodium hyaluronate are related to its mr, the higher the mr, the better the moisturizing properties. Sodium hyaluronate is rarely used alone as a humectant, and is often used in conjunction with other humectants.
Sodium hyaluronate is a biological substance inherent in the skin, and exogenous sodium hyaluronate is a supplement to the skin's endogenous ha. Sodium hyaluronate with a small mr can penetrate into the skin epidermis to promote the supply of skin nutrition and the excretion of wastes, thereby preventing skin aging and playing a role in beauty and beauty. Skin care is more important than other makeup, and it has become a modern person's awareness of beauty.
3. Repair and prevention of skin damage
Skin burns or sunburns caused by sun exposure, such as redness, blackening, peeling, etc., are mainly caused by ultraviolet rays in the sun. Sodium hyaluronate promotes the proliferation and differentiation of epidermal cells, as well as scavenging oxygen free radicals, which can promote the regeneration of the skin of the injured area, and it can also prevent it from being used in advance. Its mechanism of action is different from the commonly used ultraviolet absorbers in sunscreens. Therefore, the mixed use of ha and ultraviolet absorbers in sunscreen skin care products has a synergistic effect, which can simultaneously reduce the transmission of ultraviolet rays and the effect of a small amount of ultraviolet rays. Skin damage is repaired, and it plays a double protective role. The combination of sodium hyaluronate, egf and heparin can accelerate the regeneration of epidermal cells, making the skin tender, smooth and elastic. When the skin suffers a mild burn or scald, applying an aqueous cosmetic containing sodium hyaluronate on the surface can relieve pain and accelerate the healing of the skin on the injured area.
4. Lubricity and film formation
Sodium hyaluronate is a high molecular polymer with strong lubricity and film-forming properties. Skin care products containing sodium hyaluronate have obvious lubrication and good hand feeling when applied. After being applied to the skin, a film can be formed on the surface of the skin to make the skin feel smooth and moist, and protect the skin. Hair care products containing ha can form a layer of film on the surface of the hair, play the role of moisturizing, lubricating, hair care, and eliminating static electricity, so that the hair is easy to comb and is elegant and natural.
Sodium hyaluronate has a very high viscosity in an aqueous solution, and its 1% aqueous solution is gel-like, and it can be added to cosmetics for thickening and stabilization.