Iso E Super Aroma Chemical
CAS# 54464-57-2

The registered trade name by International Flavors & Fragrances (IFF) is Iso E Super®, and this is also the most commonly used name in the industry. As a fully synthetic compound that does not occur in nature, its origin story is a classic example of creativity in fragrance chemistry. The molecule was created at IFF in 1973 by chemists researching compounds with woody and ambergris-like notes. In appearance, Iso E Super is a clear liquid, colorless to pale yellow, with an odor described as dry, smooth woods with an ambergris nuance and a lightly floral accent.

Synthesized and patented by IFF in 1973, Iso E Super was initially used only at low dosages. A major turning point came in 1988 when perfumer Jean Louis Sieuzac boldly used it at a very high concentration (25%) in Dior’s Fahrenheit. The tremendous success of Fahrenheit not only ushered in a new era for the use of this molecule, but also cemented its status. Since then, the compound has been used extremely widely-from mass-market fragrances to distinctive niche perfumery-and it also appears in personal care and home care products to boost and improve lasting power.

Description

Iso E Super is classified in the Woody and Ambery family. In a fragrance formula, it plays multiple key roles-as an enhancer, a modifier, and a fixative-and is typically considered part of the base notes.

The scent of Iso E Super is relatively abstract and elusive. It is often described as a dry, smooth, almost transparent cedarwood-like note that gives a warm, slightly sweet ambergris effect with a soft, powdery touch. An interesting characteristic of this molecule is that some people can experience temporary olfactory “blindness” when smelling it on its own. Although its odor intensity is not especially strong, Iso E Super has excellent diffusion and radiance. Its substantivity is also very tenacious, reportedly lasting over 200 hours on a blotter.

In a formula, Iso E Super has an almost magical ability to make other notes appear brighter and more diffusive. It helps smooth and knit materials together, adding depth and body to the overall scent without significantly changing their inherent character. It is particularly effective at enhancing floral and woody notes.

Some classic pairings that set trends in the industry include the high-dose use of Iso E Super in Fahrenheit (Dior, 1988) and Trésor (Lancôme, 1990). More recently, perfumer Geza Schoen created a phenomenon with Molecule 01 (Escentric Molecules, 2006), a fragrance composed solely of Iso E Super, designed to fully explore its unique effect and the highly individualized way it behaves on skin. Technically, because it is liquid and readily soluble in alcohol and other common solvents, Iso E Super can be used directly in formulas without complex processing.

Applications

Iso E Super is one of the most widely used ingredients in the fragrance industry and is present in the vast majority of modern perfumes for both men and women. Beyond fine fragrance, it is also widely used in personal care products such as shower gels, shampoos, and body lotions, as well as in home care products including laundry detergents, fabric softeners, scented candles, and room sprays.

However, the use of Iso E Super is tightly regulated due to its potential to cause skin sensitization. According to the 49th amendment of the International Fragrance Association (IFRA), the maximum permitted level in products such as perfume (Category 4) is 21.4%. Because it is identified as a potential allergen, European Union regulations require manufacturers to list its chemical name (often Tetramethyl Acetyloctahydronaphthalenes) on the ingredient label if its concentration exceeds the relevant threshold.

Iso E Super’s popularity is evidenced by its presence in many well-known products on the market. Representative examples include Escentric Molecules’ Molecule 01, Dior Fahrenheit, Lancôme Trésor, Hermès Terre d’Hermès, and Dolce & Gabbana Light Blue.