ISO E Super (chemical name: 7-acetyl-1,2,3,4,5,6,7,8-octahydro-1,1,6,7-tetramethyl naphthalene) is a synthetic aroma chemical widely used in modern perfumery. It is celebrated for its unique, woody, and ambery scent, which adds depth, warmth, and complexity to fragrances. Below is a detailed explanation of ISO E Super, including its properties, uses, and significance in perfumery.
1. Chemical Structure and Properties
- Chemical Name: 7-acetyl-1,2,3,4,5,6,7,8-octahydro-1,1,6,7-tetramethyl naphthalene
- IUPAC Name: 1,2,3,4,5,6,7,8-octahydro-1,1,6,7-tetramethyl-naphthalen-2-ol
- Molecular Formula: C₁₅H₂₆O
- Molecular Weight: 222.37 g/mol
- Appearance: A colorless to pale yellow liquid.
- Odor: Woody, ambery, musky, and slightly floral with a velvety, skin-like quality.
- Solubility: Insoluble in water but soluble in alcohol and oils, making it suitable for use in perfumes and cosmetic formulations.
- Boiling Point: Approximately 134°C (273°F) at 0.1 mmHg.
- Stability: Stable under normal conditions but can degrade under strong acids, bases, or UV light.
2. Discovery and Development
ISO E Super was first synthesized in the 1970s by International Flavors & Fragrances (IFF). It was initially created as a cost-effective alternative to natural ambergris, a rare and expensive material derived from sperm whales. Over time, ISO E Super gained popularity for its unique scent profile and versatility in modern perfumery.
3. Role in Perfumery
ISO E Super is a versatile fragrance ingredient with several key roles:
- Base Note: It is often used as a base note in perfumes, providing a long-lasting, warm, and woody foundation.
- Blending Agent: It harmonizes well with other woody, amber, and musky notes, creating a balanced and complex scent profile.
- Enhancer: It enhances the overall structure of a fragrance, adding depth, warmth, and radiance.
- Fixative: It helps stabilize and prolong the scent of a perfume by slowing down the evaporation of more volatile components.
4. Fragrance Profile
ISO E Super contributes the following olfactory characteristics to a perfume:
- Woody: Adds a smooth, cedarwood-like warmth.
- Ambery: Provides a rich, resinous, and slightly sweet undertone.
- Musky: Imparts a soft, skin-like, and velvety quality.
- Radiant: Creates a subtle, diffusive, and airy effect, enhancing the overall projection of the fragrance.
5. Common Uses in Perfumes
ISO E Super is a staple in many fragrance families, including:
- Woody Fragrances: It is a key component in woody perfumes, particularly those featuring cedarwood, sandalwood, and vetiver.
- Amber Fragrances: Its warm and resinous qualities make it ideal for amber and oriental compositions.
- Musky Fragrances: It enhances the soft, skin-like, and velvety notes in musky perfumes.
- Modern Fragrances: Its unique and multifaceted scent profile makes it popular in avant-garde and niche perfumery.
6. Safety and Regulation
ISO E Super is generally considered safe for use in cosmetics and fragrances when used within recommended concentrations. Key points include:
- IFRA Compliance: The International Fragrance Association (IFRA) sets guidelines for the maximum allowable concentration of ISO E Super in different product types to ensure safety.
- Allergen Potential: It is not classified as a significant allergen, but it is always recommended to conduct patch tests to ensure it does not cause adverse reactions in sensitive individuals.
7. Advantages in Perfumery
- Versatility: It blends well with a wide range of fragrance materials, including woods, ambers, and musks.
- Longevity: Its fixative properties help prolong the lifespan of a perfume on the skin.
- Diffusion: Its radiant and airy qualities enhance the overall projection and sillage of a fragrance.
- Cost-Effectiveness: As a synthetic ingredient, it is more affordable than natural alternatives with similar scent profiles.
8. Limitations
- Overuse: Due to its popularity, it can be overused in some fragrances, leading to a generic or “synthetic” smell.
- Regulatory Restrictions: Compliance with IFRA and EU regulations may restrict its use in certain formulations.
9. Example Perfumes Featuring ISO E Super
ISO E Super is found in numerous iconic fragrances, including:
- Molecule 01 by Escentric Molecules: A minimalist fragrance that features ISO E Super as the sole ingredient, showcasing its unique scent profile.
- Terre d’Hermès by Hermès: Enhances the woody and earthy accords.
- Santal 33 by Le Labo: Complements the sandalwood and musky notes.
10. Conclusion
ISO E Super is a fundamental aroma chemical in modern perfumery, prized for its woody, ambery, and musky characteristics. Its ability to act as a base note, fixative, and enhancer makes it indispensable in creating warm, complex, and long-lasting fragrances. While it is generally safe, its potential for overuse necessitates careful formulation and adherence to regulatory guidelines. Its versatility and unique scent profile ensure its continued prominence in the fragrance industry.