Ceteth-5 is a synthetic non-ionic surfactant and emulsifying agent primarily used to stabilize oil-in-water emulsions. By reducing surface tension, it ensures that diverse cosmetic components remain uniformly blended and spreadable during application.
- INCI Name:
- Ceteth-5
- Chemical/Scientific Name:
- Polyethylene glycol (5) cetyl ether; Polyoxyethylene (5) cetyl ether
- Common Aliases:
- PEG-5 Cetyl Ether, POE(5) Cetyl Ether
| Category: | Surface-Active Substances |
| Source Origin: | Synthetic (derived from ethoxylation of Cetyl Alcohol) |
| Comedogenic Rating: | 2-3 |
| Primary Industries: | Cosmetics, Dermatology, Personal Care |
| Solubility: | Dispersible in Aqua; Soluble in alcohol and various oils. |
At a Glance: Properties & Effects
| Texture Enhancement: | |
| Formula Stability: | |
| Irritation Risk: |
- Primary Benefits:
- Prevents the separation of aqueous and lipid-based components in lotions and creams.
- Improves the tactile “slip” of a product, allowing for even distribution across the skin.
- Acts as a wetting agent to enhance the solubility of other active ingredients.
- Potential Risks:
- May cause mild sensitivity in individuals with compromised skin barriers.
- Moderate comedogenic potential depending on the total formulation concentration.
Biological Action & Cosmetic Profile
Structurally, this ingredient belongs to the polyethylene glycol (PEG) ethers of Cetyl Alcohol. The “5” in the name indicates the average number of repeating ethylene oxide units in the hydrophilic chain. This specific molecular weight gives the ingredient an amphiphilic nature, meaning it possesses both water-loving and oil-loving regions. This duality allows it to sit at the interface of oil and Aqua, effectively preventing droplets from coalescing.The Hydrophilic-Lipophilic Balance (HLB) of this substance is approximately 9.2. Because this value falls in the middle of the HLB scale, it is often employed as a co-emulsifier or a coupling agent to bridge the gap between more extreme surfactants. It is particularly effective at creating stable emulsions when paired with higher HLB ingredients like Ceteareth 20.Formulations containing this ether benefit from enhanced viscosity control. It does not provide significant physiological benefits to the skin cells directly, but it ensures that actives like Glycerin or Niacinamide are delivered in a homogenous medium. By maintaining the structural integrity of the cosmetic matrix, it ensures the preservation of the product’s shelf life and sensory profile.
Broader Applications & Origins
While primarily a cosmetic staple, these ethoxylated alcohols are frequently found in hair conditioners and cleansing milks. In hair care, they help distribute conditioning oils without leaving a heavy, waxy residue. The synthesis process involves the ethoxylation of fatty alcohols, which can be derived from vegetable oils, such as palm or coconut oil, though the final ingredient is considered a laboratory-processed synthetic.
Routine Integration
- Synergies:
- Fatty Alcohols: Works exceptionally well with Stearyl Alcohol and Cetyl Alcohol to create thick, luxurious textures.
- Humectants: Helps stabilize high concentrations of Glycerin and Sorbitol within oil-heavy creams.
- Lipids: Aids the integration of Stearic Acid into fluid emulsions.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel has evaluated the safety of alkyl ethyl ethers, including the Ceteth series. Their consensus concludes that these ingredients are safe for use in cosmetics when formulated to be non-irritating. Since the manufacturing process involves ethoxylation, reputable suppliers perform purification steps to ensure that trace impurities, such as 1,4-dioxane and ethylene oxide, are removed or kept below established safety thresholds. Peer-reviewed dermatological studies generally classify it as a low-risk sensitizer, making it suitable for most skin types provided the overall formulation is balanced.
Is Ceteth-5 safe for sensitive skin?
Generally, yes. While it is a surfactant, it is non-ionic and typically gentler than anionic surfactants like sulfates. However, those with known PEG sensitivities should patch test products first.
Does this ingredient cause acne?
It has a moderate comedogenic rating. In leave-on products with high concentrations, it may contribute to pore clogging for acne-prone individuals, but it is rarely the sole cause of breakouts in standard formulations.
Is it considered a “natural” ingredient?
No. Although it starts with a fatty alcohol that may be plant-derived, the ethoxylation process is a synthetic chemical reaction, classifying the final product as synthetic.