Repechage Hydra Dew Pure Gentle Foaming Cleanser

Glycerin, also known as glycerol, is a versatile and widely used humectant in skincare formulations. This colorless, odorless, viscous liquid is derived from both natural and synthetic sources, including vegetable oils and petrochemicals. As a hygroscopic substance, glycerin attracts and retains moisture, making it highly effective in hydrating and moisturizing the skin.

In skincare products, glycerin typically comprises 0.5% to 5% of the formulation. It functions by drawing water from the environment and deeper skin layers to the surface, enhancing skin hydration and improving barrier function. This moisture-binding property helps to reduce transepidermal water loss, leading to smoother, more supple skin.

Glycerin's low molecular weight allows it to penetrate the stratum corneum, providing hydration to deeper skin layers. It also exhibits emollient properties, helping to soften and smooth the skin's surface. Additionally, glycerin has been shown to enhance the penetration of other active ingredients in skincare formulations.

While generally well-tolerated, high concentrations of glycerin can potentially cause a tacky feel on the skin or draw out too much moisture in low-humidity environments. Therefore, it is often combined with other moisturizing agents for optimal efficacy and skin feel.

Limonene is a naturally occurring cyclic terpene found abundantly in the essential oils of citrus fruits, particularly lemons and oranges. This colorless liquid hydrocarbon possesses a fresh, citrusy aroma and is widely used in skincare formulations for its fragrance and potential therapeutic properties.

In skincare, limonene functions as a penetration enhancer, facilitating the absorption of other active ingredients. It exhibits antimicrobial and anti-inflammatory properties, potentially aiding in the treatment of acne and other skin infections. Some studies suggest limonene may have antioxidant effects, helping to neutralize free radicals and protect skin from oxidative stress.

However, limonene can be a skin sensitizer and irritant for some individuals, especially when oxidized. It is prone to oxidation when exposed to air, potentially leading to the formation of allergenic compounds. As a result, proper formulation and storage are crucial to maintain its stability and minimize the risk of adverse reactions.

Limonene is regulated in cosmetics and must be declared on ingredient lists when present above certain concentrations. Its use is generally considered safe when formulated appropriately, but patch testing is recommended for individuals with sensitive skin or known citrus allergies.

Phenoxyethanol is a widely used preservative in cosmetic and personal care products. This synthetic compound, derived from phenol and ethylene oxide, plays a crucial role in preventing microbial growth and extending product shelf life. With its chemical formula C8H10O2, phenoxyethanol appears as a colorless, oily liquid with a faint rose-like odor.

Effective against a broad spectrum of bacteria, yeasts, and molds, phenoxyethanol is particularly valuable in water-based formulations. It functions optimally at pH levels between 3 and 8.5, making it compatible with a wide range of skincare and cosmetic products. Typically used at concentrations of 0.5% to 1%, phenoxyethanol is considered safe for most individuals when used as directed.

While phenoxyethanol offers excellent preservation properties, it is often combined with other preservatives for enhanced efficacy. Its stability in the presence of sunlight and compatibility with other cosmetic ingredients contribute to its popularity among formulators. However, some individuals may experience skin irritation or allergic reactions, particularly at higher concentrations. Regulatory bodies, including the FDA and EU Cosmetics Regulation, have approved phenoxyethanol for use in cosmetics within specified limits, reflecting its established safety profile when used appropriately.

Propanediol, also known as 1,3-propanediol, is a versatile and increasingly popular ingredient in skincare formulations. This clear, colorless liquid is derived from corn sugar through a fermentation process, making it a sustainable alternative to petroleum-based glycols. Propanediol functions as a solvent, humectant, and emollient in skincare products, offering multiple benefits for the skin.

As a humectant, propanediol attracts and retains moisture, helping to keep the skin hydrated and plump. Its low molecular weight allows for efficient penetration into the skin, enhancing the delivery of other active ingredients. This property makes it an excellent choice for improving the efficacy of various skincare formulations.

Propanediol also acts as a preservative booster, helping to maintain product stability and extend shelf life. It has a low irritation potential, making it suitable for sensitive skin types. Additionally, this ingredient can improve the texture and spreadability of products, enhancing the overall user experience.

In cosmetic formulations, propanediol is commonly used in concentrations ranging from 1% to 10%, depending on the product type and desired effects. Its multifunctional nature and skin-friendly profile make it a valuable addition to a wide range of skincare products, from serums and moisturizers to toners and masks.