ALCOHOL DENAT. (alcool dénaturé)

À quoi il sert

Fonctions déclarées par les fabricants :

Agent antimousse : Limite la mousse pendant la fabrication ou dans le produit fini.

Élimine la mousse en cours de fabrication ou réduit la tendance des produits finis à produire de la mousse.

Agent antimicrobien : Aide à limiter le développement des micro-organismes sur la peau.

Aide à contrôler le développement des micro-organismes sur la peau.

Agent astringent : Sert à resserrer la peau.

Resserre la peau.

Parfum.

Solvant : Dissout d’autres substances pour les incorporer à la formule.

Dissout d'autres substances.

Agent de contrôle de la viscosité : Rend le produit plus ou moins épais pour ajuster sa consistance.

Augmente ou diminue la viscosité des produits cosmétiques.

Ce que dit la règle

Aucune règle européenne ne vise cet ingrédient en particulier. Il reste soumis à la règle générale : chaque produit doit faire l'objet d'une évaluation de sa sécurité avant d'être vendu (article 10 du règlement (CE) n° 1223/2009), sous la responsabilité du fabricant.

À quoi il sert

Usages consommateurs

Adhesion/cohesion promoter

Usages consommateurs

Anti-adhesive/cohesive

Usages consommateurs

Anti-freeze agent

Molécule présente naturellement dans des plantes ou des organismes ; l'ingrédient utilisé en cosmétique peut en être extrait, obtenu par fermentation ou synthétisé : l'étiquette ne dit pas lequel.

Fondement : un CAS CosIng et présence naturelle recensée dans Wikidata (base LOTUS).

Présence naturelle recensée dans Wikidata (base LOTUS) : 74 taxons ; exemples : Parthenium argentatum, Parthenium confertum, Citrus paradisi, Citrus reticulata, Vaccinium angustifolium.

Fabrication

Direct catalytic hydration of ethylene. ... Ethylene and deionized water (molar ratio range 1:0.3 -1:0.8) are heated to 250 - 300 °C at 6-8 MPa by passage through a heat exchanger and a superheater. Since hydration is exothermic, the gaseous reaction products leave the reactor at a temperature 10-20 °C higher than when they entered and thus are used as a source of heat in the heat exchanger. Some phosphoric acid is entrained by the gas stream and is neutralized by injecting a dilute solution of sodium hydroxide. After condensation and separation of the liquid reaction products, the gas is freed from residual ethanol by water washing and then recompressed and recycled to the reactor. The phosphoric acid lost by entrainment and evaporation is replaced continuously or periodically by spraying it on the catalyst bed. Crude product collects in the sump of the washer and contains ca. 10-25 wt% ethanol. It is decompressed to recover the dissolved ethylene, which is recycled. The ethanol is then purified, ideally by extractive distillation followed by rectification, to obtain a 95 vol% ethanol-water azeotrope. The azeotrope can be dehydrated by azeotropic distillation to give anhydrous ethanol.

Fabrication

Indirect hydration of ethylene ... The feed gas must contain a minimum of 35 vol% ethylene and only inert gases such as methane and ethane. ... The absorption of ethylene increases almost linearly with pressure. Operating pressure is generally 1-3.5 MPa, the higher pressure being used when the ethylene level in the feed is low. Each mole of sulfuric acid absorbs up to 1.4 mol of ethylene. The absorption is carried out with 94 - 98 wt % sulfuric acid in wash towers at 65 - 85 C. ... The resulting liquid is agitated for several hours under pressure to complete the reaction. Hydrolysis is usually performed in two stages. First, diethyl sulfate is hydrolyzed at a low temperature (70 °C) in the presence of less than the equivalent amount of water. Then more water is added gradually, and the temperature is raised to ca. 100 °C. Hydrolysis is complete within 1 hr, and the sulfuric acid is then diluted to 40-55 wt%. The ethanol formed is recovered, together with the diethyl ether byproduct, in a stripping column. The product mixture is then washed with sodium hydroxide solution to neutralize any acid, and the diethyl ether is removed in the ether distillation column. The ethanol is purified by distillation and concentrated to give a 95 vol% ethanol-water azeotrope.

Fabrication

Manufactured by fermentation of starch, sugar, and other carbohydrates; from ethylene, acetylene, sulfite waste liquors, and synthesis gas (CO + H); by hydrolysis of ethyl sulfate, and oxidation of methane.

Aspect

Clear, colorless, very mobile liquid

Odeur décrite

Alcohol odor

Odeur décrite

Fragrant odor

Présent dans 8,0 % des cosmétiques relevés (1 777 sur 22 321), surtout : déodorants, protections solaires, eaux de toilette.