This high-performance ester serves as a lightweight emollient and efficient solvent, particularly prized for its ability to dissolve and stabilize organic sunscreens. It delivers a sophisticated, “dry” skin feel while enhancing the spreadability of complex oil phases without leaving a greasy residue.
- INCI Name:
- Diethylhexyl Malonate
- Chemical/Scientific Name:
- Bis(2-ethylhexyl) malonate
- Common Aliases:
- Propanedioic acid, 1,3-bis(2-ethylhexyl) ester; DEHM
| Category: | Softeners |
| Source Origin: | Synthetic |
| Comedogenic Rating: | 0-1 |
| Primary Industries: | Cosmetics, Sun Care, Personal Care |
| Solubility: | Oil-soluble (Lipophilic) |
At a Glance: Properties & Effects
| Texture Enhancement: | |
| Formula Stability: | |
| Penetration Enhancement: | |
| Irritation Risk: |
Primary Benefits:
- Imparts a silky, non-oily finish to lipid-rich formulations.
- Functions as a superior solvent for crystalline UV filters such as Avobenzone.
- Enhances the uniform distribution of pigments and active ingredients across the skin surface.
- Provides excellent oxidative stability compared to natural plant oils.
Potential Risks:
- Minimal risk of irritation, though highly sensitive individuals should always patch test new formulations.
- Inert nature means it provides sensory benefits rather than direct biological repair.
Biological Action & Cosmetic Profile
Molecular behavior is defined by its branched-chain structure, which prevents the ingredient from packing tightly, resulting in a low-viscosity fluid with exceptionally high spreadability. This chemical architecture allows it to bridge the gap between heavy oils and volatile silicones, offering the substantive feel of an oil with the rapid absorption associated with esters. By reducing the surface tension of the oil phase, it ensures that actives are delivered in a thin, even film rather than in localized clusters.Interactions with the skin’s stratum corneum are primarily physical rather than biochemical. It fills the microscopic gaps between desquamating corneocytes, instantly smoothing the skin’s texture and reducing transepidermal water loss (TEWL) by forming a breathable, hydrophobic barrier. While it does not integrate into the lipid bilayer like ceramides, its presence helps maintain a soft, pliable surface.From a formulation perspective, this ingredient acts as a “carrier” solvent. Many high-efficacy ingredients, particularly crystalline sunscreens, are notoriously difficult to keep in solution. Diethylhexyl Malonate exhibits a high solubilizing capacity, preventing the recrystallization of these actives, which would otherwise lead to a gritty texture and reduced efficacy.
Broader Applications & Origins
Formulators frequently leverage this ester in “dry oil” sprays and lightweight facial serums where a traditional oil like Caprylic Capric Triglyceride might feel too heavy. Its synthetic origin ensures a high degree of purity and a lack of odor or color, making it an ideal choice for fragrance-free or sensitive skin lines.Versatility extends to color cosmetics, where it serves as a wetting agent for pigments in foundations and lipsticks. By ensuring pigments are thoroughly coated and dispersed, it prevents streaking and improves the color payoff of the product. Because it is highly stable, it does not go rancid over time, extending the shelf life of the final product compared to unsaturated botanical oils.
Routine Integration
Synergies:
- Organic UV Filters: Highly synergistic with Avobenzone and Octocrylene for enhanced photostability and skin feel.
- Lipid-Soluble Antioxidants: Improves the delivery and stability of Tocopherol and Tetrahexyldecyl Ascorbate.
- Mineral Pigments: Aids in the suspension of Titanium Dioxide and Iron Oxides for smoother application.
Conflicts:
- No known biochemical conflicts; however, in purely water-based serums without an emulsifier, it will phase-separate due to its lipophilic nature.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel has evaluated alkyl esters and malonates, concluding they are safe for cosmetic use as currently practiced. Dermatological testing, including Repeat Insult Patch Tests (RIPT), consistently shows that Diethylhexyl Malonate is non-sensitizing and non-irritating. Its low comedogenic potential makes it suitable for most skin types, including those prone to congestion. Furthermore, it is not listed as a restricted substance under EU CosIng regulations, affirming its broad global acceptance as a safe emollient.
Is Diethylhexyl Malonate a silicone?
No, it is a synthetic ester derived from malonic acid. While it provides a silky feel similar to some silicones, it is chemically distinct and offers different solubility profiles, particularly for UV filters.
Does this ingredient cause breakouts?
Current data suggests it has a very low comedogenic rating (0-1), meaning it is unlikely to clog pores. It is often used in “oil-free” or “non-greasy” formulations designed for acne-prone skin.
Why is it found in so many sunscreens?
It is one of the most effective solvents for chemical sun filters. It helps keep the filters dissolved in the formula, which is critical for maintaining the labeled SPF protection and preventing the product from feeling “sandy.”