Patent GB-809731-A (GB)
Title: Organosiloxane greases
Filed: 1957-06-27
Abstract: A lubricating grease comprises a major proportion of a liquid organopolysiloxane, a thickening agent in amount to thicken the siloxane to the consistency of a grease, and from 0.01 to 0.1 per cent by weight of the siloxane of benzotriazole.  The siloxanes specified contain alkyl, aryl, alkaryl, aralkyl, alkenyl, cycloaliphatic or halogenated hydrocarbon radicals.  Thickening agents specified are metal salts of fatty acids having at least 8 C atoms in the molecule where the metals are Al, Pb, Zn, Mg, Li, Na, K, Ca, Ba, Sr, Cu, Mn, Hg, Bi, Cr, Fe, Co or Ni, as disclosed in Specification 688,166; metal salts of alicyclic substituted fatty acids having a chain length of from 2 to 6 C atoms, as disclosed in Specification 666,360, along with soaps of hydroxy fatty acids or their glycerides; lithium 2 - ethyl - hexoate, hydroxystearate, myristate or caprate; phthalocyanine; carbon black, as disclosed in Specification 628,878; oxides, particularly in their aerogel form, e.g. silica, alumina and iron oxide, as disclosed in Specification 605,036, [Group IV (a)], titania, zinc oxide, fume silica, diatomaceous earth, clay and calcium carbonate; aluminium benzoatestearate, octadecanoyl urea and N,N1-acetyl stearoyl-p-phenylenediamide.  The anhydrides of alkyl or alkenyl succinic or glutaric acids in which the alkyl or alkenyl radicals contain 8 to 23 C atoms may be added, e.g. in amount of from 0.01 to 0.5 per cent by weight of the siloxane, to impart corrosion resistance to the greases when in contact with ferrous metals.  Other optional additives include pigments, antioxidants and lubricity improvers.  Examples are given.  The compositions of Specification 807,503 are disclaimed.ALSO:A grease composition comprises a major proportion of a liquid organopolysiloxane, a thickening agent in amount sufficient to thicken the liquid to the consistency of a grease, and from 0.01 to 0.1 per cent by weight of the siloxane of benzotriazole.  The siloxanes specified contain alkyl, aryl, alkaryl, aralkyl, alkenyl, cycloaliphatic or halogenated hydrocarbon radicals. Thickening agents specified are metal salts of fatty acids having at least 8 C atoms in the molecule where the metals are, e.g., Al, Pb, Zn, Mg, Li, Na, K, Ca, Ba, Sr, Cu, Mn, Hg, Bi, Cr, Fe, Co or Ni, as disclosed in Specification 688,166; metal salts of alicyclic substituted fatty acids having a chain length of from 2 to 6 C atoms, as disclosed in Specification 666,360, along with soaps of hydroxy fatty acids or their glycerides; lithium 2-ethyl-hexoate, hydroxystearate, myristate or caprate; phthalocyanine; carbon black, as disclosed in Specification 628,878; oxides, particularly in their aerogel form, e.g. silica, alumina and iron oxide, as disclosed in Specification 605,036; titania, zinc oxide, fume silica, diatomaceous earth, clay and calcium carbonate; aluminium benzoate stearate, octadecanoyl urea and N,N1-acetyl stearoyl - p - phenylenediamide. The anhydrides of alkyl or alkenyl succinic or glutaric acids in which the alkyl or alkenyl radicals contain 8 to 23 C atoms may be added in amount, e.g. of from 0.01 to 0.5 per cent by weight of the siloxane to impart corrosion resistance to the greases when used in contact with ferrous metals.  Other optional additives include pigments, antioxidants and lubricity improvers.  Examples are given. The compositions of Specification 807,503 are disclaimed.  Uses: as lubricants, damping media and as dielectric and sealing compounds in ignition systems and electronic equipment; also used to prevent corrosion in the splicing of copper wire.