viewBox="0 0 20 20" fill="none" width="20" height="20" aria-hidden="true"> Fragrance

ALPHA-ISOMETHYL IONONE
Synthetic Fragrance (Ionone Derivative)

ALPHA-ISOMETHYL IONONE is produced synthetically through chemical modification of ionones originally isolated from violets. Learn everything about its origin, effect, and the best application in your daily skincare routine here.

Also known as: Isomethyl Ionone, Gamma-Methylionone, Iraldein

Substance Class Synthetic Fragrance (Ionone Derivative)

INCI Name ALPHA-ISOMETHYL IONONE

CAS Number 127-51-5

Quality EU Cosmetics Regulation compliant

viewBox="0 0 24 24" fill="none" width="32" height="32" aria-hidden="true"> What is ALPHA-ISOMETHYL IONONE?

Alpha-Isomethyl Ionone is a synthetic fragrance from the ionone family, originally isolated from violets and now produced chemically. The substance imparts a characteristic floral-powdery scent note to cosmetic products with woody undertones, reminiscent of iris, lily of the valley, and classic powder perfumes. In skincare, it is primarily used as a masking agent to cover functional odors of active ingredients such as retinol or peptides. Due to its allergenic potential, Alpha-Isomethyl Ionone is one of the 26 fragrances subject to declaration under the EU Cosmetics Regulation and must be listed separately in the INCI list starting at very low concentrations.

viewBox="0 0 24 24" fill="none" width="32" height="32" aria-hidden="true"> Where does ALPHA-ISOMETHYL IONONE come from?

It is produced synthetically through chemical modification of ionones originally isolated from violets (Viola odorata). The substance is created through methylation and isomerization, creating a more stable and cost-effective alternative to natural violet scent. In modern cosmetics, extraction and processing are subject to strict quality standards according to EU Cosmetics Regulation (EC) No. 1223/2009. RAU Cosmetics exclusively sources cosmetic-grade raw materials from verified suppliers.

viewBox="0 0 24 24" fill="none" width="32" height="32" aria-hidden="true"> How does ALPHA-ISOMETHYL IONONE work on a cellular level?

Binds to olfactory receptors in the nasal mucosa and creates a floral-woody scent with a violet note. In cosmetic formulations, the substance acts as a masking agent that covers unpleasant inherent odors of other ingredients. Due to its lipophilic structure, it adheres well to the skin surface and ensures a long-lasting scent.

viewBox="0 0 24 24" fill="none" width="32" height="32" aria-hidden="true"> Dosage & Regulation

Typical use concentration: Typically 0.001-0.1% in perfumes and skincare products, up to 0.014% in leave-on products according to EU limits

How it works on your skin

Fragrance Masking

Covers the characteristic inherent odor of functional ingredients such as niacinamide, peptides, or retinol. The violet note with woody undertones particularly neutralizes chemical or metallic scent notes. This significantly improves the sensory acceptance of highly concentrated active ingredient formulations.

Floral-Powdery Scent Note

Imparts a classic feminine scent character to products, reminiscent of iris, violet, and lily of the valley. The woody facets provide depth and prevent the scent from appearing too sweet. In perfumery, the note is often referred to as 'Powdery Floral' and is typical of elegant, timeless compositions.

Fragrance Fixation

Acts as a fragrance component with medium volatility (middle note), harmonizing the transition between volatile top notes and heavy base notes. The lipophilic structure enables good adhesion to the skin, making the scent perceptible for several hours.

Allergenic Potential (Warning)

Belongs to the 26 fragrances subject to declaration in the EU, as about 1-2% of the population are sensitized. Can trigger allergic contact dermatitis in predisposed individuals, especially with repeated exposure in leave-on products. Patch tests show reactions starting at 0.5% concentration in sensitized individuals.

Who is it for?

Non-sensitive Skin

Can improve the floral-elegant scent character of care products, provided there is no fragrance sensitivity.

Normal Skin

Masks functional odors of active ingredients such as retinol or peptides and contributes to the sensory product experience.

In your routine

Product selection for sensitivity

If you are prone to fragrance allergies or have already reacted to perfumes, avoid products with this ingredient completely. Pay attention to the INCI list — Alpha-Isomethyl Ionone must be declared from 0.001% in leave-on products.

Patch test before first use

Apply a small amount of the product to the inside of your forearm and wait 24-48 hours. In case of redness, itching, or burning, wash off immediately and do not use the product.

Application on intact skin

Avoid application on irritated, inflamed, or injured skin, as the penetration of the fragrance is increased and the risk of sensitization rises.

Combination with other fragrances

If you use several perfumed products (serum, cream, body lotion), the exposure adds up. In case of known sensitivity, reduce the number of perfumed products in your routine.

Storage: Relatively stable to light and air, but sensitive to strong acids (pH <3) and strong bases (pH >9). In formulations with high concentrations of ascorbic acid or AHAs, the pH value should be buffered. Shelf life in closed containers at room temperature is several years.

Frequently Asked Questions

Why is Alpha-Isomethyl Ionone listed separately in the INCI list even though 'Parfum' is also given?

Since the 7th amendment of the EU Cosmetics Directive (2003), 26 particularly common allergy-triggering fragrances must be declared separately, even if they are part of a perfume composition. Alpha-Isomethyl Ionone is one of them because about 1-2% of the population are sensitized to it. The declaration obligation applies from 0.001% in leave-on products (creams, serums) and from 0.01% in rinse-off products (shampoos, shower gels). This allows allergy sufferers to specifically avoid the substance.

Is Alpha-Isomethyl Ionone more dangerous than other fragrances?

Not generally more dangerous, but it is among the more common contact allergens among fragrances. In patch test studies, about 1-2% of tested persons react positively, which is in the medium range (for comparison: balsam of Peru approx. 3-5%, oakmoss up to 2%). The sensitization rate is dose-dependent — higher concentrations in leave-on products increase the risk. For non-sensitized persons, the substance is harmless when used normally.

Where does the typical 'powder scent' of Alpha-Isomethyl Ionone come from?

The powdery note arises from the specific molecular structure with a methyl group on the ionone ring. This configuration resembles the scent profile of iris root (orris) and violets, which naturally contain ionones. In the nose, the same olfactory receptors are activated as with natural iris extracts, which were traditionally used in powders. The woody undertone comes from the ketone function, which also occurs in cedarwood fragrances.

Can one become allergic to Alpha-Isomethyl Ionone even after years of use?

Yes, fragrance allergies can develop with a delay. Sensitization often occurs after repeated exposure over months or years — this is known as acquired contact sensitization of type IV (delayed type). Particularly risky is the combination of: frequent use, high concentration, damaged skin barrier (e.g., through retinoids or acids), and genetic predisposition. Once sensitized, the allergy usually remains for life.

Are there natural alternatives to Alpha-Isomethyl Ionone for violet scent?

Natural violet extracts (Viola odorata) contain the related substances alpha-ionone and beta-ionone, but are significantly more expensive and less stable. Iris root extract (orris) also provides a powdery note, but costs up to €50,000/kg and matures for 3-5 years. In 'Clean Beauty,' ionones from raspberry ketone fermentation are sometimes used; these are chemically similar and also potent allergens. A completely allergen-free alternative for this specific scent note does not exist.

Discover the Power of ALPHA-ISOMETHYL IONONE

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Details

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Hydration + SPF. Your morning routine, simplified. Hyaluron Cream SPF10 — Daily Moisturizer with Hyaluronic Acid & UV Protection Your morning skincare just got easier. RAU's Hyaluron Cream SPF10 combines deep Hyaluronic Acid hydration with daily UV protection in a single, lightweight moisturizer. It's designed for the woman who wants her skin to look luminous, feel comfortable, and stay protected — without layering five products before 8am. Absorbs fast, wears beautifully under makeup, and keeps skin hydrated all morning. Note: SPF10 provides daily UV protection for incidental exposure. For prolonged sun exposure, layer with a dedicated broad-spectrum SPF30+ product. ☀ Daily UV Shield SPF10 helps protect skin from incidental sun exposure during your everyday routine 💧 Hyaluronic Hydration Helps skin retain moisture for a plump, comfortable feel throughout the morning ✍ Makeup-Ready Finish Lightweight, fast-absorbing texture — wears smoothly under foundation or on its own Active Ingredients What's Working For Your Skin Hyaluronic Acid Attracts and binds moisture to the skin surface — helps visibly plump and smooth the complexion UV Filters (SPF10) Provides daily protection against UVA/UVB rays for routine outdoor activities — commuting, errands, office windows Panthenol (Vitamin B5) Helps soothe and condition — leaves skin soft, calm, and comfortable Your Ritual How to Use Hyaluron Cream SPF10 1 Last step AM — Apply as the final step of your morning skincare routine, after serum 2 Apply — Warm a small amount in fingertips and smooth evenly over face and neck 3 Let absorb — Wait 1-2 minutes before applying makeup for best wear 4 Extended sun exposure? — Layer a dedicated SPF30+ sunscreen on top when spending time outdoors Made in Germany SPF10 Daily UV Paraben-Free Fragrance-Free 50 ml / 1.7 fl oz $50.99 Free shipping on orders over $60. Ships internationally from Germany. Estimated delivery: 7-14 business days to the US.

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Stimulation of collagen synthesis: Detailed view of Bakuchiol powder, representing firmer skin and anti-aging.

Details

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resist aging! Rich Cream with Bakuchiol ✔ rich & moisturising face cream ✔ can prevent and smooth wrinkles ✔ for the regeneration of thinning, mature & light-damaged skin ✔ developed & produced in Germany Skin type The face cream is suitable for dry, dehydrated & mature skin. Application Apply to cleansed skin and massage in. CAN - tighten the skin- smooth wrinkles- moisturise- protect against premature ageing- prevent dehydration- soothe the skin Hazard statements Our resist aging! Rich Cream with Bakuchiol is a rich anti-aging day and night cream for dry, dehydrated and mature skin. The combination of active ingredients: The main active ingredient used, bakuchiol, is extracted from the seeds of the babchi plant. In traditional Chinese medicine and Ayurveda, the plant has long been used as a remedy for numerous skin problems. Due to its antimicrobial effect, the active ingredient is used against skin blemishes, for example. 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TOCOPHERYL ACETATE - Antioxidant - skin nourishing PANTHENOL - panthenol - regenerates and renews damaged skin, soothes and reduces inflammation, promotes cell growth CAPRYLYL GLYCOL - caprylyl glycol - nourishes the skin and makes it smooth and soft SERINE - amino acid - keeps the skin in good condition, improves the smell of the product UREA - urea - has keratolytic and anti-itching properties and moisturising effect GLYCERYL CAPRYLATE - glyceryl caprylate - enables the formation of emulsions, keeps the skin supple ASCORBYL PALMITATE - antioxidant - makes the product durable and improves the smell of the product LACTIC ACID - moisturising, skin caring, regulates / stabilises the pH-value of cosmetic products SODIUM L ACTATE - sodium salt of lactic acid - moisturising, helps remove dead skin cells from the skin surface MAGNESIUM SULFATE - Magnesium sulphate - increases or decreases viscosity (toughness) of product STEARIC ACID - Surfactant - emulsion stabilising, cleansing, refatting, perfuming DIETHYLAMINO HYDROXYBENZOYL HEXYL BENZOATE - diethylamino-hydroxybenzoyl-benzoic acid hexyl ester - protects the skin from UV radiation TOCOPHEROL - Vitamin E - antioxidant, skin caring, gives the product a pleasant fragrance TETRASODIUM GLUTAMATE DIACETATE - stabiliser - influences stability and quality of the product PHENYLPROPANOL - fragrance/solvent - improves the smell of the product SODIUM CHLORIDE - common salt - improves the smell of a product, swelling, viscosity control PARFUM (FRAGRANCE) - fragrance CITRIC ACID - citric acid - reduces horny skin, blackheads, acne scars, fine wrinkles, widens/deepen pores PROPYLENE CARBONATE - Propylene carbonate - Increases or decreases viscosity (toughness) of product SODIUM HYDROXIDE - Caustic soda - regulates and stabilises the pH of the product STEARALKONIUM HECTORITE - Stearalkonium Hectorite - money forming, increases or decreases the viscosity (toughness) of the product HYDROGENATED PALM GLYCERIDES CITRATE - esterification product with citric acid - makes the skin smooth and supple ETHYLHEXYL METHOXYCINNAMATE - Octinoxate - protects against UV radiation PHENOXYETHANOL - Phenoxyethanol - antimicrobial, protects the product from spoilage SODIUM SULFITE - Sodium sulphite - Antioxidant, preservative POTASSIUM SORBATE - potassium salt - protects the product from microbial spoilage and gives the product a pleasant smell SODIUM BENZOATE - sodium salt - protects the product from microbial spoilage and gives the product a pleasant smell BENZYL SALICYLATE - salicylic acid benzyl ester - protects the product from damage by UV light, improves the smell of the product LINALOOL - fragrance LIMONENE - fragrance ALPHA-ISOMETHYL IONONE - gamma methyl ionone - fragrance, skin conditioning

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Ab wann sieht man Ergebnisse mit Retinol Serum?

Erste Verbesserungen der Hauttextur nach 4 bis 6 Wochen. Anti-Aging-Effekte wie weniger Falten und mehr Festigkeit nach 12 bis 16 Wochen.

Kann ich Retinol Serum täglich anwenden?

Start mit 2x pro Woche abends — nach 4 Wochen auf 3 bis 4x steigern. Empfindliche Haut: 1x wöchentlich beginnen. Sonnenschutz am Folgetag ist Pflicht.

Retinol vs. Bakuchiol — was ist besser?

Retinol ist der klinisch am besten belegte Anti-Aging-Wirkstoff. Bakuchiol wirkt ähnlich, ist pflanzlich — ideal für Schwangere und sehr empfindliche Haut.