Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Organic compound containing boron
Reexamination Certificate
2002-03-22
2004-01-13
Howard, Jacqueline V. (Department: 1764)
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Organic compound containing boron
C508S291000, C508S295000, C508S390000
Reexamination Certificate
active
06677281
ABSTRACT:
FIELD OF INVENTION
The present invention relates to industrial lubricants. More specifically the invention relates to lubricants for industrial machinery that provides improved rust protection, deposit control and demulsibility.
BACKGROUND
The art of lubricating oil formulation has become more complex with ever more stringent standards dictated by the increasing complexity of industrial equipment technology. For example, industrial oils and circulating oils such as compressor, gear, and hydraulic oils typically are required to be capable of separating from water in order that any water contamination arising during use does not adversely impact equipment operation and durability. In addition to industrial lubricants having demulsification properties, these oils are also required to be thermally and oxidatively stable in order to minimize deposit formation caused by degradation products. To further enhance deposit control performance industrial lubricants typically employ dispersants to keep deposit-forming precursors suspended in the bulk oil and away from working surfaces. Dispersants, however, tend to be effective in emulsifying water in the oil phase. Thus, additives that may enhance one property may adversely effect another property.
Another required property of industrial oils is rust inhibition.
An object of the present invention therefore is to provide an industrial lubricant that provides rust protection, deposit control and is capable of demulsifying water.
SUMMARY OF INVENTION
It has now been found that a specific balance of a metallic and ashless rust inhibitor and a dispersant provides improved anti-rust and demulsibility performance. Accordingly, in one embodiment, a lubricant composition is provided comprising:
(a) a lubricating oil basestock;
(b) an effective amount of a rust inhibitor additive combination consisting essentially of a metal containing rust inhibitor and an ashless rust inhibitor; and
(c) an ashless polyolefin dispersant wherein the weight ratio of dispersant to rust inhibitor additive combination is less than 1.14.
Other embodiments of the invention will become apparent from the detailed description which follows.
DETAILED DESCRIPTION OF INVENTION
The lubricating oil basestock comprising a major portion of the composition of the present invention has a viscosity in the ISO 10-1500 viscosity grade range and preferably ISO 32 to 680 viscosity grade range. Individual oils meeting this viscosity requirement can be used or a mixture of oils of different viscosities can be combined. Preferably the basestock will be selected from any of the natural mineral oils of API Group II basestocks.
The lubricant composition also includes an effective amount of a rust inhibitor additive combination consisting essentially of a metal containing rust inhibitor and an ashless rust inhibitor. In the combination the metal containing rust inhibitor preferably is selected from Group 2
a
metal sulfonates. Indeed, the preferred metal sulfonates are calcium and barium alkylaryl sulfonates. Examples of such sulfonates include calcium dinonyl naphthalene sulfonate, barium dinonyl naphthalene sulfonate, and neutral calcium sulfonate.
The metal sulfonate typically is used in an amount in the range of about 0.20 to about 0.50 wt % based on the lubricating composition and preferably in the range of 0.20 to 0.30 wt %.
Combined with the metal sulfonate rust inhibitor is an ashless rust inhibitor. The ashless rust inhibitor preferably is an alkenyl succinimide, especially alkenyl succinimides having alkenyl groups of from about 15 to about 30 carbon atoms.
The ashless rust inhibitor typically is used in an amount in the range of from about 0.05 to about 0.30 wt % based on the lubricating composition.
The composition of the present invention includes an ashless polyolefin dispersant. Preferred polyolefin dispersants include homo- and copolymers of ethylene, propylene, butylene, isobutylene, pentene and the like. These polymer dispersants will have weight average molecular weights in the range of about 800 to about 5000 and preferably from about 2000 to about 2500. Preferably the dispersant is borated. Indeed, an especially preferred borated ashless dispersant is a borated polyisobutylene having a weight average molecular weight in the range of about 2000 to about 2500.
Unexpectedly it has been found that the weight ratio of dispersant to rust inhibitor combination should be less than 1.14 and preferably in the range of 0.55 to 1.14.
Other conventional additives which can be used in the lubricants of this invention include oxidation inhibitors, antifoam agents, viscosity index improvers, pour point depressants, and the like. These include hindered phenols, alkylated diphenyl amines, benzotriaozole derivatives, silicone oils and the like.
In general these other additives can be used in total amounts ranging from about 1.5 to 5 wt %.
REFERENCES:
patent: 3254025 (1966-05-01), Le Suer
patent: 3661622 (1972-05-01), Rogers
patent: 3671012 (1972-06-01), Scott et al.
patent: 3720615 (1973-03-01), Izumi et al.
patent: 4010107 (1977-03-01), Rothert
patent: 4159956 (1979-07-01), de Vries
patent: 4419252 (1983-12-01), Shim
patent: 4493776 (1985-01-01), Rhodes
patent: 5137980 (1992-08-01), DeGonia et al.
patent: 5262073 (1993-11-01), Schmitt et al.
patent: 5312554 (1994-05-01), Waddoups et al.
patent: 5334318 (1994-08-01), Vinci et al.
patent: 5498353 (1996-03-01), Lin et al.
patent: 5525247 (1996-06-01), Miyaji et al.
patent: 5656582 (1997-08-01), Shiraishi et al.
patent: 5672570 (1997-09-01), Miyaji et al.
patent: 5789356 (1998-08-01), Tiffany, III
patent: 5888948 (1999-03-01), Meny et al.
patent: 5942472 (1999-08-01), Watts et al.
patent: 5962377 (1999-10-01), Baumgart et al.
patent: 5962378 (1999-10-01), Tiffany et al.
patent: 6001780 (1999-12-01), Ho et al.
patent: 85102059 (1985-04-01), None
patent: 0096539 (1983-12-01), None
patent: 0113045 (1984-07-01), None
patent: 0208560 (1987-01-01), None
patent: 0307132 (1989-03-01), None
patent: 0462319 (1991-12-01), None
patent: 0686689 (1995-12-01), None
patent: 0721978 (1996-07-01), None
patent: 0976810 (2000-02-01), None
patent: 104845 (1989-06-01), None
patent: 1421762 (1986-10-01), None
patent: WO 88/03552 (1988-05-01), None
patent: WO 94/13762 (1994-06-01), None
patent: WO 95/10584 (1995-04-01), None
patent: WO 96/35765 (1996-11-01), None
patent: WO 97/12016 (1997-04-01), None
D. Clark et al., “New Generation of Ashless Top Tier Hydraulic Fluids”, Journal of the Society of Tribologist and Lubrication Engineers, Apr. 2000, pp. 22-23.
Helen Ryan, Ethyl Petroleum Additives Ltd., Use of Group II, Group III Base Stocks in Hydraulic and Industrial Applications, 5th Annual Fuels & Lubes Asia Conference, pp. 1-17.
Fessenbeck et al., “Additives for Environmentally Acceptable Lubricants”, National Lubricating Grease Institute, V 60, Sep. 6, 1996, pp. 9-25 (Abstract only).
H. Huang et al., “Study on Rustproofing Lubricating Oil 801”, Journal -Runhua Yu Mifeng (1982), (4), pp. 16-21, Chinese Language.
Galiano-Roth Angela Stefana
Givens, Jr. Willie Allan
Bakun Estelle C.
ExxonMobil Research and Engineering Company
Howard Jacqueline V.
LandOfFree
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