What Is Diisononyl Isoeicosanedioate?
Diisononyl Isoeicosanedioate is a lab made ester produced by reacting octadecanedioic acid with two branched isononyl alcohols. The union of these parts creates a clear lightweight liquid oil that feels silky on skin. It first gained attention in the late 1990s when formulators looked for modern alternatives to heavier oils that could still soften skin and boost spreadability.
Manufacturing involves an esterification step in which the acid and alcohol are gently heated with a catalyst, then the mixture is purified to remove any leftovers. The final material is stable against heat and light which helps finished products keep their quality longer.
You will often find Diisononyl Isoeicosanedioate in face and body moisturizers, anti aging creams, overnight masks, makeup primers, lipsticks, sunscreens and other leave on treatments designed for dry or mature skin.
Diisononyl Isoeicosanedioate’s Cosmetic Benefits/Uses
In formulas this ingredient serves two key roles
- Skin Conditioning: Forms a light protective film that reduces water loss so skin stays supple smooth and comfortable
- Emollient: Fills tiny spaces between skin cells creating a soft even surface and giving creams a pleasant glide without a greasy feel
Who Can Use Diisononyl Isoeicosanedioate
This silky ester suits most skin types including dry, normal and combination because it delivers moisture without a heavy afterfeel. Oily or acne prone skin typically tolerates it as well, though those who break out very easily may prefer lighter gels or lotions.
Diisononyl Isoeicosanedioate is made entirely from synthetic building blocks so it is acceptable for vegans and vegetarians and no animal testing is required for its manufacture.
The ingredient is not listed as restricted during pregnancy or breastfeeding and current safety data show low absorption through intact skin. That said this is not medical advice and anyone who is pregnant or nursing should clear all skincare products with their doctor first.
It does not increase sensitivity to sunlight and can be used day or night without raising the risk of sunburn. It also plays well with common actives such as retinoids, vitamin C and acids, helping formulas feel smoother and less drying.
Potential Side Effects/Adverse Reactions
Responses to topical Diisononyl Isoeicosanedioate can vary from person to person. The points below list potential reactions yet most users will not experience them when the ingredient is properly formulated and used as directed.
- Mild redness or stinging on very sensitive skin
- Allergic contact dermatitis in individuals who are specifically sensitized
- Temporary clogged pores or small comedones in users extremely prone to acne
- Eye irritation if the product is accidentally rubbed into the eyes
If any adverse reaction occurs stop using the product and seek advice from a qualified healthcare professional.
Comedogenic Rating
Rating: 1/5
Diisononyl Isoeicosanedioate is a lightweight branched ester that spreads easily and leaves minimal residue so it is far less likely to trap oil or debris inside pores than heavier plant butters or waxes. Most lab and consumer reports show a very low incidence of clogged pores which is why formulators use it in many non greasy moisturizers and makeup. For this reason it is generally suitable for people who are prone to acne or breakouts. Because the molecule is synthetically uniform it also resists oxidation, a process that can raise comedogenicity in natural oils.
As with any emollient, the final formula matters: if combined with high levels of occlusive waxes or comedogenic pigments the overall product could still cause congestion even though this single ingredient rates low.
Summary
Diisononyl Isoeicosanedioate is primarily a skin conditioning agent and emollient. It creates a light protective film that slows water loss, fills micro gaps between skin cells for a smoother surface, and gives creams or makeup a silky glide without greasy weight. These benefits stem from its branched molecular structure which lets it slip over skin easily and resist crystallizing.
The ester is not a household name like glycerin or shea butter yet its popularity has grown steadily, especially in modern lightweight formulations that aim to mimic the feel of silicones while staying biodegradable.
Current safety assessments classify it as low risk with minimal absorption through intact skin and no evidence of endocrine disruption. Still, every skin is unique so it is wise to patch test any new product that contains this ingredient to make sure it agrees with your individual tolerance.