Silica, also known as fumed silica, is widely used in cosmetics. Its high specific surface area, small particle size and high adsorption make it play multiple roles in cosmetic formulas. The following are the specific uses of silica in cosmetics:

1. Adsorbent
Fragrance adsorption: Silica can be used to adsorb fragrances, which not only helps to maintain the stability of fragrances, but also controls its release rate, making the fragrance of cosmetics more durable and evenly released.
Oil and moisture adsorption: In powdered cosmetics, such as facial care products and antiperspirants, silica can absorb excess oil and moisture, help keep the skin dry, and improve the use effect of the product. 

2. Thickener and stabilizer
Thickening effect: Adding silica to cosmetics such as ointments, gels, and creams can significantly thicken the product and increase the viscosity and stability of the product. 
Improve storage stability: As an efficient anti-caking agent and free-flowing agent in cosmetics and eye care products, silica can improve the storage stability of products and the dispersibility of powdered products.

3. Thixotropy and spreadability
Improve thixotropy: The three-dimensional "chain" structure (branch structure) and surface silanol of silica enable it to form an "interpenetrating network" between silica and the matrix in the system, thus showing good thixotropy. This makes the cosmetics added with silica feel even and smooth when applied, without astringency. 

4. Improve color and texture
Uniform color: In cosmetics such as lipstick, silica can increase viscosity, improve overall stability, and help evenly distribute pigments, prevent discoloration, and make the makeup more durable and natural. 
Fine texture: As a filler and thickener in cosmetics such as foundation and eye shadow, silica can make the product more delicate and smooth, and improve the use experience. 

5. Safety
Non-toxic and harmless: White carbon black is a non-toxic, odorless, pollution-free nano inorganic material with stable chemical properties. It is insoluble in water, acid (except hydrofluoric acid) and organic solvents, but soluble in alkali and hydrofluoric acid. This makes it very safe to use in cosmetics. 
In summary, white carbon black plays multiple roles in cosmetics, such as adsorbent, thickener, stabilizer, thixotropy improver, and color and texture enhancer. With the continuous development of nanomaterial technology and the improvement of people's requirements for cosmetic quality, the application prospects of white carbon black in cosmetics will be broader.