6 ingredients
Solvent
Explore all 6 ingredients in the Solvent category. Learn about their benefits and find products that contain them.
Water
Water (INCI: Aqua) is the most common cosmetic ingredient, used as the primary solvent to dissolve and carry water-soluble actives, humectants, and other ingredients in a formulation. Cosmetic-grade water is purified and deionised to remove mineral ions, which improves product stability and prevents microbial contamination. It forms the base of most creams, serums, toners, and lotions.
Learn more →Dipropylene Glycol
Dipropylene glycol is a clear, colourless liquid that functions primarily as a solvent and viscosity-decreasing agent in cosmetic formulations. It helps dissolve other ingredients and improve product spreadability, while also providing mild moisturising properties by acting as a humectant that attracts water to the skin.
Learn more →t-Butyl Alcohol
T-Butyl Alcohol (INCI: t-Butyl Alcohol; IUPAC: 2-methylpropan-2-ol) is a small branched-chain alcohol that appears as a clear liquid with a camphor-like odour. In cosmetic formulations it is used primarily as a solvent to dissolve other ingredients and improve product texture, as a denaturant in alcohol-based products, and occasionally as a perfuming agent. It is typically present at low concentrations as a functional excipient rather than an active ingredient.
Learn more →Alcohol
Alcohol (INCI: Alcohol, also known as ethanol) is a simple, volatile alcohol used in cosmetics primarily as a solvent, antimicrobial agent, astringent, and viscosity controller. It creates cosmetically elegant, fast-absorbing, thin formulas by dissolving ingredients that are insoluble in water or oil. It is a controversial ingredient: while it provides immediate sensory and preservative benefits, it can be drying and potentially barrier-disrupting when present at high concentrations.
Learn more →Hexylene Glycol
Hexylene glycol (2-methylpentane-2,4-diol) is a multi-functional helper ingredient used primarily as a solvent to thin out thick formulations and improve product spreadability. It also enhances the efficacy of preservative systems — notably in blends like Lexgard HPO where it boosts phenoxyethanol performance — and functions as a mild surfactant and emulsifier.
Learn more →Ethoxydiglycol
Ethoxydiglycol (INCI: Ethoxydiglycol; also known as diethylene glycol monoethyl ether or DEGEE) is a clear, odourless liquid solvent and humectant used widely in cosmetics and pharmaceuticals. It excels at dissolving and stabilising challenging actives — including vitamin C, benzoyl peroxide, and dihydroxyacetone (DHA) — and also acts as a penetration enhancer, helping other actives absorb more deeply into the skin. It is permitted in EU cosmetics under Annex III (entry 297), meaning it is restricted rather than banned, with safety assessments by the SCCS confirming it is safe at authorised concentrations.
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