Isobutyl Benzoate
molecular structure · PubChem
AKA: 120-50-3, 2-Methylpropyl benzoate, BENZOIC ACID, 2-METHYLPROPYL ESTER, Benzoic acid, Isobutyl ester, FEMA No. 2185
Synthetic
Preservative
Solvent
Not Clean
Isobutyl benzoate is a benzoate ester obtained by the formal condensation of benzoic acid with isobutanol. It has a role as a metabolite. It is functionally related to a benzoic acid and an isobutanol.
Solubility insoluble in water; soluble in organic solvents, oils
Formula
C11H14O2
Mol. Weight
178.23
CAS #
120-50-3
Form
Liquid
State
colourless oily liquid with a green, floral, leafy odour
Functions
Preservative
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Solvent
Dissolves other ingredients so they distribute evenly in the formula. Often the invisible "base" everything else is mixed into.
Moisturizing
Antioxidant
Prevents microbial growth
Provides scent
Dissolves other ingredients
Traditional Use
A synthetic ester created through 20th-century organic chemistry synthesis. Employed in cosmetics as an emollient and solvent, particularly in nail products and fragrance formulations.
EWG
4
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not Phototoxic
medical-approval
all-shades-safe
Concentration Guide
0.5%
0%1%
Reg. Limit
EU regulatory limit: 0.5%. Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 1a.
Regulatory Agencies
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed1 review →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR