Many consumers come across the term ‘bentonite’ when reading the ingredient lists of cosmetics and notice that some products contain this chemical substance. Today, we’d like to take a closer look at what bentonite actually is.

Bentonite, also known as soapstone. In cosmetics and skincare products, bentonite primarily acts as an adsorbent. It has a risk rating of 2, is relatively safe, and can be used with confidence. It generally has no adverse effects on pregnant women, nor does it cause acne.

Bentonite is a non-metallic mineral whose primary mineral component is montmorillonite. The structure of montmorillonite consists of a 2:1 crystal structure, formed by two silicate tetrahedra sandwiching a layer of alumino-oxygen octahedra.

As the layered structure formed by the montmorillonite unit cells contains certain cations—such as Cu, Mg, Na and K—and the bonds between these cations and the montmorillonite unit cells are highly unstable, making them easily exchangeable with other cations, it possesses excellent ion-exchange capacity.

Overseas, it has been applied in over 100 sectors across 24 fields of industrial and agricultural production, featuring in more than 300 products; consequently, it is often referred to as ‘high-energy clay’.

As bentonite possesses exceptional properties such as powerful cleansing, detoxification, itch relief and skin-brightening, alongside characteristics including hygroscopicity, water-absorption and swelling, suspension, dispersion, stability, thixotropy, water-dispersibility, thickening ability and non-toxicity, it has become an essential ingredient in cosmetics and an ideal raw material for the development of natural products.

★★★  Applications in Face Masks

 

Montmorillonite, the active component in bentonite, possesses moisture-retaining, skin-cleansing and adsorbent properties. When added to face masks, it exhibits excellent water absorption, absorbing excess oil and impurities from the face, adsorbing bacteria on the skin’s surface, increasing viscosity to prevent suspended particles from settling, and acting as a stabilising emulsifier; it is therefore widely used in face masks.

 

★★★  Applications in Facial Cleansers

 

Due to bentonite’s unique internal network structure, it possesses ion-exchange capacity, adsorbent properties, moisture-retention and skin-cleansing capabilities, as well as the ability to facilitate transdermal absorption of active ingredients. It can effectively remove and adsorb residual make-up, dirt and impurities from skin creases, whilst also absorbing excess sebum, exfoliating dead skin cells and accelerating their shedding. Consequently, bentonite serves as an excellent filler in facial cleansers.

 

★★★  Applications in Body Lotions

 

The unique network structure of bentonite enables a large amount of free water to be converted into bound water, thereby increasing its viscosity. Body lotions often contain appropriate amounts of organic and inorganic gelling agents to enhance the emulsion’s stability. High-purity modified bentonite can form a thixotropic gel of the non-Newtonian fluid type in aqueous solutions, making it an ideal emulsion stabiliser in cosmetics.

 

★★★  Application in Concealer Products

 

Bentonite and white carbon black (i.e. hydrated silica) are forms of silica in the form of fine powders or ultrafine particles. They are commonly used in sunscreen, foundation, tinted moisturiser and primer-type concealer products, offering excellent concealing and brightening effects, as well as providing a certain degree of water resistance in sunscreen products.

As bentonite is difficult to disperse during the production of cosmetic formulations, Nano physically modifies the bentonite by pre-dispersing it with various oils to produce a bentonite gel. This gel offers a fresh, silky-smooth feel on the skin, disperses easily, simplifies the production process, and reduces time and energy consumption.

 

■■■ Bentonite Gel (D5 Silicone Oil)

 

1. This product has already been blended with a silicone oil emulsifier; adding a small amount of W/O emulsifier to the actual formulation is sufficient to produce water-in-oil (W/O) products, making it convenient to use;

 

2. Products formulated in W/O or W/Si systems exhibit excellent stability, resolving issues such as separation and oil separation caused by heat or prolonged storage;

 

3. Production is straightforward, greatly simplifying the manufacturing process; it disperses easily in various oil phases, ensuring consistent viscosity of the final product across batches;

 

4. Products formulated using this emulsifier in W/O or W/Si systems have a light texture and glide smoothly upon application.

 

■■■ Bentonite Gel (Isododecane)

 

1. Improves the stability of low- or medium-viscosity W/O or W/Si systems, resolving the issue of oil separation in water-in-oil products caused by heat or prolonged storage;

 

2. Possesses oil-controlling properties, enhancing the refreshing feel of W/O or W/Si system products;

 

3. Enhances the compatibility of sunscreen agents in water-in-oil systems, improving the stability of sunscreen BB products and increasing the SPF value;

 

4. Easy to manufacture, it greatly simplifies the production process; it disperses readily in various oil phases, ensuring consistent viscosity between batches of the final product.

 

The bentonite gel developed by Nano has significantly expanded its range of applications, improved its compatibility and stability, made it easier to disperse, simplified the production process, and reduced time and energy costs—making it an excellent cosmetic ingredient!