Edition: BP 2025 (Ph. Eur. 11.6 update)
General Notices
Non-ionic Emulsifying Wax
Action and use
Emulsifying agent.
DEFINITION
Cetostearyl Alcohol 800 g
Macrogol Cetostearyl Ether (22) 200 g
Extemporaneous preparation
The following directions apply.
Melt together and stir until cold.
CHARACTERISTICS
A white or almost white, waxy solid or flakes melting when heated to a clear almost colourless liquid.
Practically insoluble in water, producing an emulsion; moderately soluble in ethanol (96%); partly soluble in ether.
IDENTIFICATION
A. Incinerate at a temperature not exceeding 450° until free from carbon and cool. The residue is negligible (distinction from Emulsifying Wax).
B. Complies with the test for Sulfated ash.
TESTS
Acid value
Not more than 0.5, Appendix X B.
Refractive index
At 60°, 1.435 to 1.439, Appendix V E.
Solidifying point
45° to 53°, Appendix V B, using the following modifications. Place in the inner test tube sufficient of the melted substance to fill the tube to a depth of about 50 mm. Stir the substance gently and steadily, without scraping the wall of the tube, while the tube and its contents are allowed to cool. The temperature at which the level of the mercury in the thermometer remains stationary for a short time is regarded as the solidifying point.
Alkalinity
Dissolve 10 g in 10 mL of water and 10 mL of ethanol (96%). Not more than 0.5 mL of 0.1M hydrochloric acid VS is required for neutralisation using phenolphthalein solution R1 as indicator.
Hydroxyl value
175 to 192, Appendix X D. Use 3.5 g.
Saponification value
Not more than 2.0, Appendix X G. Use 20 g.
Sulfated ash
Not more than 0.1%, Appendix IX A.
