Frostschutz und Enteisungsmittel

A de-icing and anti-freezing material in the form of a viscous, stable, oil-in-water emulsion comprises a major proportion of water and a minor proportion of oil or grease, together with a quantity of solute as a freezing-point depressant in the aqueous phase and a "water-absorbing compound", and is stabilized by a cationic or non-ionic emulsifying agent active at the interface. By "water-absorbing compound" is meant a substance which will absorb substantial quantities of water with little change of viscosity of either itself or the material as a whole; examples are sodium carboxymethyl cellulose, sodium alginate, hydroxyethyl cellulose, gelatin or starch. The oily phase may be a naphthenic mineral oil optionally containing colloidal graphite or molybdenum disulphide. The solute is preferably a corrosion inhibitor such as sodium nitrite, but common salt or urea may also be used. Polymers, e.g. polyisobutylene, or a mixture of polyethylene glycol or glycerol with sugar residues, or hydrogenated castor oil may be included as thixotropic agents, and sorbitol as a humectant. A preferred emulsifier is a mixture of diethylene glycol monostearate and an alkyl trimethyl ammonium chloride.