A robust, vegetable-based emulsifier specifically engineered for water-in-oil (W/O) systems. This high-performance ingredient excels at stabilizing formulations with high pigment loads and significant mineral content.
- INCI Name:
- Polyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate
- Chemical/Scientific Name:
- Polyglyceryl-4 diisostearate polyhydroxystearate sebacate
- Common Aliases:
- Isolan GPS
| Category: | Emulsifiers |
| Source Origin: | Plant-derived (typically from Glycerin, Isostearic Acid, and ricinoleic acid) |
| Comedogenic Rating: | 0-1 |
| Primary Industries: | Dermatological Sunscreens, Protective Creams, Color Cosmetics |
| Solubility: | Oil-soluble |
At a Glance: Properties & Effects
| Formula Stability: | |
| Texture Enhancement: | |
| Hydration/Moisture: | |
| Irritation Risk: |
- Primary Benefits: Exceptional stabilization of W/O emulsions, facilitates cold-process manufacturing, enhances pigment dispersion, and improves water resistance.
- Potential Risks: Generally considered non-irritating and non-sensitizing; extremely rare potential for mild congestion in highly oil-sensitive skin.
Biological Action & Cosmetic Profile
The molecular structure of this ingredient functions as a powerful polymeric surfactant. Unlike traditional emulsifiers that may require heat to integrate, this ester allows for cold-process formulation, preserving the integrity of heat-sensitive active substances. Its chemical architecture consists of polyglycerol-4 units esterified with a combination of diisostearic, polyhydroxystearic, and sebacic acids. This complexity provides a broad range of polarity, making it highly effective at bridging the gap between water droplets and the surrounding oil phase.
Stability remains its hallmark trait. Formulators utilize this ingredient to create low-viscosity lotions or heavy creams that remain stable even in the presence of high electrolyte concentrations. Because it forms a resilient film around water droplets, it prevents phase separation in challenging environments, such as high-temperature storage or during the application of mechanical shear. This film-forming ability also contributes to the “water-resistant” claims found in many athletic sunscreens and long-wear foundations.
Sensory characteristics are significantly improved when this polyglyceryl ester is used. It mitigates the greasy or heavy feel often associated with traditional water-in-oil products. Instead, the resulting emulsions provide a smooth, velvety skin feel with excellent spreadability. This is particularly beneficial for products containing inorganic UV filters like Zinc Oxide or Titanium Dioxide, as it ensures an even distribution of particles across the skin surface, preventing streaking or white casts.
Broader Applications & Origins
Environmental sustainability drives the adoption of this ingredient. It is typically derived from renewable vegetable sources, such as rapeseed and castor oil, aligning with “green chemistry” standards. Beyond sunscreens, it is a staple in “barrier creams” designed for compromised skin. Its ability to maintain a continuous oil phase on the skin surface mimics the natural lipid barrier, providing a physical shield against transepidermal water loss (TEWL).
Routine Integration
- Synergies: Works exceptionally well with Magnesium Sulfate (Epsom salts) to further stabilize the internal water phase. It is a preferred partner for Caprylic Capric Triglyceride and mineral-based sun-protection agents.
Clinical Consensus & Safety
Dermatological reviews by the Cosmetic Ingredient Review (CIR) Expert Panel and classifications in the EU’s CosIng database categorize this polyglyceryl ester as safe for use in cosmetics. Toxicology data indicates it lacks significant dermal irritation or sensitization potential. Because of its large molecular weight, the ingredient does not penetrate the skin barrier, instead remaining on the stratum corneum to perform its functional and protective duties. Clinical usage in “baby care” and “sensitive skin” categories further validates its mild safety profile.
Is this ingredient vegan and natural?
Yes, it is typically derived from 100% vegetable-based raw materials and is approved for use in many “natural” and “clean” beauty standards, though it undergoes synthetic processing to achieve its final ester form.
Does it cause breakouts?
This ingredient has a very low comedogenic potential. While it is used in oil-rich formulations, the emulsifier itself is not a known pore-clogger, and it is frequently used in dermatological products for sensitive and acne-prone skin.
Why is it in my waterproof sunscreen?
It creates a water-in-oil emulsion that is naturally resistant to washing off with water or sweat. Its film-forming properties help keep UV filters locked in place on the skin during physical activity.