Diisopropyl Adipate

Diisopropyl adipate is a fatty acid ester emollient/solvent typically used at a few percent to improve slip and reduce greasiness; it is not an active and is generally well-tolerated in leave-on products. Patch testing and clinical use suggest a low rate of irritation and sensitization, but as a solvent/emollient it can occasionally sting or aggravate highly compromised eczema skin, especially in barrier-disrupted areas. Given sensitive-skin safety priorities and rare but possible reactivity, it fits best as very gentle rather than completely inert. Safety Notes: Diisopropyl Adipate is used as a lightweight emollient/solvent and slip agent, and in many mass-market leave-on lotions, sunscreens, primers, and makeup it can appear at low supporting levels (~0.1–2%) to improve spread and sensory feel. In real-world anhydrous leave-on products (makeup/primer bases, facial oils/oil-serums, silicone-free “dry oil” blends, some fragrance/body oils) it can function as a primary carrier oil and reach high levels, commonly 10–40% and in some specialty consumer products up to ~50–60%. It is less typical at high levels in rinse-off cleansers due to surfactant system constraints, where usage is usually low (often <5%) as part of the emollient phase.