Abstract:
547,972. Lubricants; oxidation inhibitors. STANDARD OIL DEVELOPMENT CO. Nov. 17, 1939, No. 30306. Convention date, Dec. 16, 1938. [A Specification was laid open to inspection under Sect. 91 of the. Acts, June 17, 1940.] [Class 91] [Also in Group IV] Lubricants comprise a hydrocarbon lubricating oil compounded with a small amount of a metal salt of a dialkyl-dihydroxy-diaryl sulphide or polysulphide or a polymer thereof or a selenide or telluride analogue. Metals specified are aluminium, barium, calcium, cobalt, chromium, magnesium, manganese, sodium, potassium, lithium, nickel, lead, tin, zinc, copper, iron and cadmium; the monovalent metals replace the hydrogen atoms of one or more of the hydroxyl groups, whilst the polyvalent metals may replace one or more of the hydroxyl groups in the same molecule or in a number of molecules of the same kind. The aryl groups may be napththyl &c. as well as phenyl, whilst the alkyl groups preferably contain 4-6 carbon atoms. The preparations of various metal salts of tert-amyl-phenol monosulphide is described and information given as to their effect, when added in quantities of up to 2 per cent. in inhibiting the oxidation of various lubricating oils. Specification 498,046 is referred to. The Specification as open to inspection under Sect. 91 also includes the subject-matter of Specification 547,973. In addition, it describes the use of metal salts of aromatic hydroxy compounds which contain any substituent in the aryl nucleus, as well as of the corresponding sulphur, selenium and tellurium compounds. Salts of the following further types of compounds are specified: alkylphenols such as tert-amylphenol and diisobutylphenol; alkylchlorphenols such as 2-chloro-4-tert-amylphenol, 2:6 dichloro- 4-tert-amylphenol and 6-chloro-2:4-diamylphenol ; dinitrophenyl-alkyphenol sulphides. All the metal salts are stated to be useful as oxidation inhibitors not only for lubricating oils but also for all petroleum oils and for fatty oils, soaps, aldehydes, synthetic resins, rubber, synthetic rubber and paper. This subject-matter does not appear in the Specification as accepted.