Name: Wax, Cetyl Esters
CAS No: Cetyl esters wax [977067-67-6]
USP-NF: Cetyl Esters Wax
Cera cetyla; Crodamol SS; Cutina CP; Liponate SPS; Protachem MST; Ritaceti; Ritachol SS; spermaceti wax replacement; Starfol Wax CG; Synaceti 116; synthetic spermaceti.
Cetyl esters wax [977067-67-6]
CnH2nO2 (where n = 26–38).470–490 The USP32–NF27 describes cetyl esters wax as a mixture consisting primarily of esters of saturated fatty alcohols (C14–C18) and saturated fatty acids (C14–C18).
Cetyl esters wax is a stiffening agent and emollient used in creams and ointments as a replacement for naturally occurring spermaceti. Cetyl esters wax is hydrophobic and has been proposed as a suitable component of an ophthalmic gelatin-based, controlledrelease delivery matrix.(1) The physical properties of cetyl esters wax vary greatly from manufacturer to manufacturer owing to differences between the mixtures of fatty acids and fatty alcohol esters that are used. Differences between products appear most obviously in the melting point, which can range from 43–478C (USP32–NF27 range) to 51–558C, depending on the mixture. Materials with a high melting point tend to contain predominantly cetyl and stearyl palmitates. See Table I.
Cetyl esters wax occurs as white to off-white, somewhat translucent flakes (typically in the range of 5 mm to several millimeters in the largest dimension), having a crystalline structure and a pearly luster when caked. It has a faint, aromatic odor and a bland, mild taste.
See Table II.
Dielectric constant 6–18 Flash point >2408C Peroxide value 40.5 Refractive index nD 60 = 1.440 Specific gravity 0.820–0.840 at 508C Viscosity (dynamic) 6.7–7.4 mPa s (6.7–7.4 cP) at 1008C Solubility High melting materials tend to be less soluble. See Table III.
Store in a well-closed container in a cool, dry place. Avoid exposure to excessive heat (above 408C).
Incompatible with strong acids or bases.
Cetyl esters wax is prepared by the direct esterification of the appropriate mixtures of fatty alcohols and fatty acids.
Cetyl esters wax is an innocuous material generally regarded as essentially nontoxic and nonirritant. LD50 (rat, oral): >16 g/kg
Observe normal precautions appropriate to the circumstances and quantity of material handled.
Included in the FDA Inactive Ingredients Database (topical preparations). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.
Spermaceti wax. Spermaceti wax CAS number [8002-23-1] Appearance Spermaceti is a waxy substance obtained from the head of the sperm whale. It consists of a mixture of the cetyl esters of fatty acids (C12–C18) with cetyl laurate, cetyl myristate, cetyl palmitate, and cetyl stearate comprising at least 85% of the total esters. It occurs as white, translucent, slightly unctuous masses with a faint odor and mild, bland taste. Iodine value 3.0–4.4 Melting point 44–528C Refractive index nD 80 = 1.4330 Saponification value 120–136 Solubility Soluble in chloroform, boiling ethanol (95%), ether, and fixed or volatile oils; practically insoluble in ethanol (95%) and water. Specific gravity 0.938–0.944 Uses Spermaceti has been used in creams, ointments, and suppositories,(2) although it has largely been superseded in pharmaceutical and cosmetics formulation by the synthetic material, cetyl esters wax. Comments The EINECS number for spermaceti wax is 232-302- 5
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