Patent GB-636941-A (GB)
Title: Lubricating oil compositions
Filed: 1944-10-18
Abstract: A lubricating oil composition, especially suitable for use in motor oils for the crankcase lubrication in Diesel, aircraft and other engines operating at high temperatures and pressures but also suitable for use in greases, cutting oils, transmission oils and heat transfer fluids, comprises a major proportion of a hydrocarbon oil of lubricating viscosity, a small amount of a detergent which is a salt of an organic acid, which term includes a phenol or thiophenol, and a small amount of an anti-oxidant corrosion inhibitor which is a selenium compound having in its molecule the structure <FORM:0636941/III/1> wherein the carbon atoms are aliphatic or alicyclic, m is a small whole number and n is zero or a small whole number.  The aliphatic or alicyclic groups may contain substituents, for example aromatic groups or polar substituents such as halogen atoms or amino or hydroxy groups.  One or more detergents and one or more different selenium compounds may be present in the oil composition which may also contain additional ingredients such as pour-point depressants, oiliness agents, extreme pressure agents, blooming agents and viscosity index improvers.  Detergents mentioned are the sodium, potassium, magnesium, calcium, barium, cadmium, zinc, aluminium, tin, nickel, ammonium, substituted ammonium and organometallic salts of various fatty acids, aryl substituted fatty acids, polar substituted aliphatic carboxylic acids, aromatic carboxylic acids, naphthenic acids, phenols, substituted phenols and thiophenols.  In the examples mineral lubricating oil compositions are described containing: (1) dicetyl selenide and calcium cetyl phenate; (2) dilauryl selenide and calcium cetyl phenate, sulphurized calcium cetyl phenate, aluminium cetyl tartrate, calcium cetyl o-hydroxybenzoate, calcium dinaphthenate or cadmium cetyl benzoate; (3) dioctyl selenide and calcium cetyl phenate or calcium stearate; and (4) dilauryl diselenide and calcium naphthenate.  Tests are described in which the mineral lubricating oil compositions are compared with similar compositions from which either the detergent or the selenium compound has been omitted.  Hydrocarbon oils other than mineral lubricating oils may be employed and amyl naphthalene and oils p  from the hydrogenation of coal or other carbonaceous matter are mentioned.  Specifications 462,793 and 633,993 and U.S.A. Specification 2,001,108, are referred to.  The Specification as open to inspection under Sect. 91 refers to hydrocarbon oil compositions containing the selenium compound and a detergent which is (a) a metal organic sulphonate; (b) a polyvalent metal salt of an organo-substituted acid of phosphorus, for example an oil-soluble polyvalent metal salt of an organo-substituted thiophosphoric acid, together with a polyvalent metal salt of a phenol, particularly an oil-soluble one; (c) a polyvalent metal salt of an N-organo-substituted dithiocarbamic acid together with a polyvalent metal organo sulphonate; (d) a salt of an organo-inorganic acid; or (e) a compound of the type (A)(X)(Z)(X1)(Rn) in which A represents a basic salt-forming substituent, X and X1 are selected from the group consisting of oxygen, sulphur and selenium, Z is an acid-forming element selected from Groups IIIa, IV, Vb and VIb of the Periodic Table, R is an organic radicle and n is a whole number.  This subject-matter does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specification 600,775.