Dibutyl adipate (DBA) is an organic compound that works as a plasticizer in plastics and an emollient in cosmetics. It’s the chemical result of combining adipic acid with butanol, creating a clear, oily liquid that makes materials more flexible and skin products feel smoother.
You’ll find this versatile ingredient in everyday products from makeup to food packaging. Its molecular formula is C₁₄H₂₆O₄, and it appears as a colorless liquid with a mild, ester-like smell that’s barely noticeable in finished products.
Chemical Identity and Structure of Dibutyl Adipate
| Property | Value |
|---|---|
| Chemical Name | Dibutyl adipate (di-n-butyl ester of adipic acid) |
| CAS Number | 105-99-7 |
| Molecular Formula | C₁₄H₂₆O₄ |
| Molecular Weight | 258.36 g/mol |
| Physical State | Clear, colorless oily liquid |
| Odor | Mild ester-like smell |
| Melting Point | -10°C |
| Boiling Point | 300-305°C at 760 mmHg |
| Density | 0.96 g/mL at 25°C |
| Water Solubility | 4-6 mg/L at 25°C (practically insoluble) |
| Vapor Pressure | 0.001-0.002 mmHg at 25°C (very low volatility) |
| Partition Coefficient (log Kow) | 4.3-4.4 |
| Other Names | Hexanedioic acid dibutyl ester, Adipic acid dibutyl ester, Cetiol B, Adimoll DB |
Common Applications of Dibutyl Adipate
- Plasticizer in polymers: Makes PVC and other plastics flexible by lowering their glass-transition temperature. It’s especially common in films, coatings, and adhesives.
- Cosmetic ingredient: Functions as an emollient and solvent in moisturizers, sunscreens, foundations, lipsticks, and hair conditioners. It helps products spread smoothly and provides a lightweight, non-greasy feel.
- Floor polish component: Makes up about 10% of certain floor waxes and polishes, creating a smooth protective film that adds gloss without quick evaporation.
- Food packaging additive: FDA-approved for use in materials that contact food, including packaging films and adhesives where it helps maintain flexibility.
- Printing ink ingredient: Serves as a plasticizing solvent that improves ink flow and adhesion properties.
- Sunscreen formulation aid: Dissolves solid organic UV filters and ensures even application on skin, improving sun protection effectiveness.
- Makeup film-former: Improves the flexibility and durability of color cosmetics like foundations and mascaras, helping them last longer on skin.
Is Dibutyl Adipate Toxic
Dibutyl adipate has low acute toxicity and is generally safe for humans at normal exposure levels. The oral LD50 in rats is 12-13 g/kg body weight, which means you’d need to consume massive amounts to experience harmful effects.
The compound can cause mild skin irritation when applied undiluted, producing slight redness and swelling that goes away quickly. However, it’s not a skin sensitizer and doesn’t cause allergic reactions in most people.
Long-term studies show no significant organ damage or health problems at doses up to 1000 mg/kg per day. The substance isn’t carcinogenic, mutagenic, or genotoxic according to multiple safety assessments by regulatory agencies.
Is Dibutyl Adipate Safe in Cosmetic Uses
Dibutyl adipate is safe for use in cosmetics at typical concentrations and has approval from major regulatory bodies worldwide. The FDA allows it in cosmetics without restrictions, and the EU’s CosIng database lists it as an approved ingredient for skin conditioning and film-forming.
The ingredient works well at low concentrations (usually 1-10% of formulations) and doesn’t clog pores, making it suitable for acne-prone skin. It’s considered non-comedogenic and provides conditioning benefits without heaviness.
Studies show excellent skin tolerance when DBA is properly formulated in products. Patch tests demonstrate good dermal compatibility, with no evidence of causing contact allergies or sensitization reactions.
Unlike some phthalate plasticizers that are banned in cosmetics, dibutyl adipate serves as a safer alternative. It doesn’t accumulate in the body and breaks down into harmless components.
FAQs
How does dibutyl adipate differ from phthalates?
Dibutyl adipate is an adipate ester that’s readily biodegradable and has lower toxicity than many phthalate plasticizers, making it a safer alternative for cosmetics and consumer products.
What happens if dibutyl adipate gets in water?
It biodegrades quickly in water, with 86-95% breaking down within 28 days, though it can harm aquatic life at concentrations above 3 mg/L.
Is dibutyl adipate natural or synthetic?
It’s a synthetic compound made by combining adipic acid with butanol through an esterification process.
Can pregnant women use products with dibutyl adipate?
At cosmetic concentrations, it’s considered safe, though the EU requires labeling due to reproductive effects seen only at extremely high doses in animal studies.