Disteardimonium Hectorite is a chemical compound derived from Hectorite, a naturally occurring colloidal clay composed of magnesium, silicates or lithium that is white in colour. It is obtained by surfactants such as stearalkonium chloride and ammonium stearate.
The name describes the structure of the molecule:
- Disteardimonium refers to a quaternary ammonium salt derived from stearic acid, a long-chain fatty acid with 18 carbon atoms. The prefix 'di-' indicates the presence of two groups derived from stearic acid.
- Hectorite is a type of naturally occurring clay mineral. It belongs to the group of smectite clays, known for their ability to swell in water. Hectorite is composed of layers of silicate (silicon, oxygen and other elements) encased in a layer of magnesium hydroxide.
The synthesis process takes place in different steps:
- Purification. Hectorite undergoes a purification process to remove impurities. This process typically involves a series of washing, sedimentation and centrifugation steps.
- Modification. Hectorite is modified by replacing the sodium ions present in the clay with disteardimonium ions. This is done through a process known as ion exchange. The clay is mixed with a solution of disteardimonium ions and the sodium ions present in the clay are replaced by the disteardimonium ions.
- Drying and grinding. After the ion exchange process, the modified clay is dried and then ground into a fine powder to produce Disteardimonium Hectorite.
It appears in the form of a white powder.
What it is used for and where
Cosmetics
It is a wetting and viscosity agent used predominantly in cosmetic products.
As an INCI ingredient, it acts as follows:
Viscosity control agent. It controls and adapts viscosity to the required level for optimal chemical and physical stability of the product and dosage in gels, suspensions, emulsions, solutions.
Light stabilizer. It prevents light from degrading light-sensitive components and slows down degradation reactions that have already begun. The mechanism is, in a way, similar to antioxidants and the effectiveness depends on the.complexity of the formulation and the density of the product.
Suspending agent. Non surfactant. Cosmetic or pharmaceutical suspensions are known to be thermodynamically unstable and it is therefore essential to include in the formulation a suspending agent capable of dispersing any sedimented particulates and reducing the rate of sedimentation. The presence of this agent increases the consistency of the suspension medium and exerts a protective colloidal action.
Pharmaceuticals
Disteardimonium Hectorite is used in creams, ointments, gels and topical lotions to improve product consistency and stability with stabilising and viscosising properties.
Safety
The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the safety of 4 ammonium hectorite compounds used in cosmetics: disteardimonium hectorite, dihydrogenated tallow benzylmonium hectorite, stearalkonium hectorite, and quaternium-18 hectorite. These ingredients function in cosmetics mainly as nonsurfactant suspending agents. The Panel reviewed available animal and human data and concluded that these ammonium hectorite compounds were safe as cosmetic ingredients in the practices of use and concentration as given in this safety assessment (1).
CAS 97280-96-1
EC number 306-493-1
References_____________________________________________________
(1) Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD, Liebler DC, Marks JG Jr, Shank RC, Slaga TJ, Snyder PW, Andersen FA. Safety assessment of ammonium hectorites as used in cosmetics. Int J Toxicol. 2013 Nov-Dec;32(6 Suppl):33S-40S. doi: 10.1177/1091581813507722
