Menthoxypropanediol is achemical compound, a menthol derivative used in cosmetics for its refreshing and soothing properties.

The name describes the structure of the molecule:

• Menthoxy indicates that the chemical compound contains a functional group derived from menthol. This group gives the compound refreshing and soothing properties.
• propanediol is a diol, or a type of alcohol with two -OH groups. It is known to be an effective moisturizing agent and solvent used in cosmetics to enhance the texture of products and the solubility of active ingredients.

Chemical Industrial Synthesis Process

• Reagent selection. The synthesis of Menthoxypropanediol begins with the selection of menthol, a natural organic compound known for its cooling properties, and 1,3-propanediol, an alcohol used as a solvent and moisturizing agent.
• Esterification reaction. Menthol is reacted with 1,3-propanediol in the presence of an acid catalyst to form an ester, Menthoxypropanediol. This process may require careful control of temperature and reaction time to ensure high yield.
• Purification. After the reaction, the product is purified to remove impurities and unreacted by-products. Purification can be carried out using techniques such as vacuum distillation or chromatography.
• Quality control. The final product is analyzed to ensure it meets the necessary specifications for cosmetic applications. These tests can include purity analysis, chemical structure determination, and stability testing.
• Stabilization. Sometimes, stabilizers or other additives may be added to improve the stability and compatibility of Menthoxypropanediol with other substances in cosmetic formulations.

What it is used for and where

Menthoxypropanediol  acts offering cooling benefits without the irritation that can sometimes be associated with pure menthol. It is commonly used in skincare products such as creams, lotions, and acne treatment products to enhance the sensation of freshness on the skin. This ingredient also helps to improve the penetration of other actives into the skin, making it useful in a variety of cosmetic formulations.

Cosmetics - INCI Functions

• Fragrance. It plays a very important role in the formulation of cosmetic products as it provides the possibility of enhancing, masking or adding fragrance to the final product, increasing its marketability. It is able to create a perceptible pleasant odour, masking a bad smell. The consumer always expects to find a pleasant or distinctive scent in a cosmetic product. 
• Refreshing. This ingredient is included in cosmetic products to provide a refreshing or toning sensation to the skin and can also help relieve irritation or redness.

Main uses and benefits of menthoxypropanediol.

Cooling Effect. It offers an immediate cooling sensation on the skin, making it ideal for post-sun exposure products, after-shave products, and other soothing skin formulations.

Soothing Properties. It is known for its soothing abilities, which help to calm irritated skin, making it a useful component in formulations for sensitive skin.

Enhancement of Product Sensoriality. It enhances the sensory experience of cosmetic products, adding a refreshing dimension without the strong cold sensation or tingling of pure menthol.

Skin Compatibility. Unlike menthol, which can be irritating for some people, menthoxypropanediol is generally well tolerated and can be used on more sensitive skin types.

Versatility in Formulation. It can be easily incorporated into various cosmetic formulations, including gels, lotions, creams, and lip balms.

Stability in Formulation. It shows good chemical stability and does not react easily with other ingredients, making it a reliable additive for cosmetic formulators.

Safety

Unlike menthol, which may be irritating to some people, Menthoxypropanediol is generally well tolerated and can be used on more sensitive skin (1) although its use may cause allergies in particularly sensitive skin (2).

References_____________________________________________________________________

(1) Ständer S, Augustin M, Roggenkamp D, Blome C, Heitkemper T, Worthmann AC, Neufang G. Novel TRPM8 agonist cooling compound against chronic itch: results from a randomized, double-blind, controlled, pilot study in dry skin. J Eur Acad Dermatol Venereol. 2017 Jun;31(6):1064-1068. doi: 10.1111/jdv.14041. 

Abstract. Background: Patients suffering from chronic pruritus (CP) due to dry skin with are often applying emollients containing menthol. However, topical menthol may be irritating and of weak potency in severe pruritus. Two TRPM8 agonists, (1R,2S,5R)-N-(2-(2-pyridinyl)ethyl)-2-ispropyl-5-methylcyclohexancarboxamide and menthoxypropanediol, combined as cooling compound (CC) have shown stronger activation of TRPM8 than menthol. Objectives: Objective of this study was to evaluate the efficacy and safety of CC in alleviating pruritus in patients with dry itchy skin....Conclusions: Treatment of dry and pruritic skin with a lotion containing the TRPM8 agonist combination ameliorates severe pruritus and represents a possible novel treatment for the burdensome symptom. The most suitable treatment concentration needs still to be identified. ClinicalTrials.gov: NCT00669708. © 2016 European Academy of Dermatology and Venereology.

(2) FRANKEN, Lonneke; DE GROOT, Anton; LAHEIJ‐DE BOER, Anna‐Marijke. Allergic contact dermatitis caused by menthoxypropanediol in a lip cosmetic. Contact Dermatitis (01051873), 2013, 69.6.

Abstract. The article presents a case study of a 46-year-old woman who has diagnosed with perioral erythema and scaling. She mentions to have been using several lip comestics such as lip balms. It notes that the patient had allergic contact dermatitis which is caused by menthoxypropanediol, a component in making lip cosmetics. The article also discusses the nature of methoxypropanediol which derives from menthol.