Get a Free 5ml Mini Now Free 5ml Mini With Every Order of The Mantle

ALUMINUM ISOSTEARATE.

Valuable CAS 72277-75-9 / ANTICAKING, EMULSION STABILISING, OPACIFYING, VISCOSITY CONTROLLING

A metallic soap primarily functioning as a rheology modifier and texture enhancer, organizing oil phases to increase viscosity and create gel structures. It also acts as an opacifying agent and emulsion stabilizer, contributing to a smooth skin feel.

anticaking emulsion stabilising opacifying viscosity controlling

Science

As a metallic soap, it forms a crystalline lattice within oil phases, effectively increasing viscosity and generating a gel-like texture. On skin, it helps stabilize emulsions, uniformly suspend particles like pigments or UV filters, and provides an elegant, velvet-like finish.


Research

Low confidence
Effective range N/A
Optimal

N/A

Key findings

  1. 01 Product formulations containing 2.5-2.85% Isostearic acid showed no contact sensitization in repeat insult patch tests on 333 subjects.
  2. 02 Undiluted Isostearic acid (100%) caused no irritation; Aluminum Stearate (structurally similar) demonstrated low acute dermal toxicity in guinea pig studies.

Transparency

Not commonly dusted

The Formula

Solubility
Oil
Optimal pH 3 – 9
0 7 14

Stability

It exhibits high stability against heat and mechanical stress, with a melting point of approximately 115-120°C. While insoluble in water, it readily disperses in oils and various organic solvents.

Conflicts

  • Hot mineral acids (e.g., sulfuric, nitric) which cause decomposition into isostearic acid and aluminum salts
  • Strong oxidizing agents

Safety

CIR Status
Safe as used
Max tested
24%
Sensitization risk Low

The CIR Expert Panel deemed it safe for use in current practices, with concentrations up to 24% reported in eye makeup. It should be formulated to be non-irritating and non-sensitizing to ensure optimal safety.


Your Skin

Yes Normal
Yes Dry
Yes Oily
Yes Sensitive
Irritancy Low
Comedogenicity Low

Our Assessment

Valuable

As a versatile, low-risk functional ingredient, it is valuable for enhancing product texture, stability, and aesthetic appeal across various skincare formulations.


Related

Finding similar ingredients…


References