U.S. patent application number 12/438972 was filed with the patent office on 2010-06-24 for lubricating composition.
This patent application is currently assigned to THE LUBRIZOL CORPORATION. Invention is credited to Betsy J. Butke, Carlos Cerda de Groote, Hirohito Hasegawa, Tadashi Yoshimura.
Application Number | 20100160191 12/438972 |
Document ID | / |
Family ID | 38988936 |
Filed Date | 2010-06-24 |
United States Patent
Application |
20100160191 |
Kind Code |
A1 |
Butke; Betsy J. ; et
al. |
June 24, 2010 |
Lubricating Composition
Abstract
The present invention relates to a lubricating composition
containing a dispersant, a corrosion inhibitor and an antioxidant.
The invention further provides a method for lubricating a
mechanical device with the lubricating composition.
Inventors: |
Butke; Betsy J.; (Mentor,
OH) ; Hasegawa; Hirohito; (Aichi, JP) ;
Yoshimura; Tadashi; (Aichi, JP) ; Cerda de Groote;
Carlos; (Lakewood, OH) |
Correspondence
Address: |
THE LUBRIZOL CORPORATION;ATTN: DOCKET CLERK, PATENT DEPT.
29400 LAKELAND BLVD.
WICKLIFFE
OH
44092
US
|
Assignee: |
THE LUBRIZOL CORPORATION
Wickliffe
OH
|
Family ID: |
38988936 |
Appl. No.: |
12/438972 |
Filed: |
August 28, 2007 |
PCT Filed: |
August 28, 2007 |
PCT NO: |
PCT/US07/76981 |
371 Date: |
January 28, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60824299 |
Sep 1, 2006 |
|
|
|
Current U.S.
Class: |
508/186 ;
508/273; 508/275; 508/421; 508/546 |
Current CPC
Class: |
C10N 2030/12 20130101;
C10N 2030/45 20200501; C10M 2215/064 20130101; C10M 2215/28
20130101; C10M 2223/043 20130101; C10M 2207/026 20130101; C10N
2040/135 20200501; C10N 2040/13 20130101; C10M 141/08 20130101;
C10M 2215/223 20130101; C10N 2040/12 20130101; C10N 2040/08
20130101; C10M 141/06 20130101; C10M 141/10 20130101; C10M 2207/289
20130101; C10N 2030/14 20130101; C10M 2219/106 20130101; C10N
2060/14 20130101 |
Class at
Publication: |
508/186 ;
508/546; 508/273; 508/275; 508/421 |
International
Class: |
C10M 163/00 20060101
C10M163/00; C10M 133/12 20060101 C10M133/12; C10M 135/36 20060101
C10M135/36; C10M 141/10 20060101 C10M141/10 |
Claims
1. A method for lubricating a mechanical device comprising
supplying to the mechanical device an ashless lubricating
composition comprising: (a) a dispersant; (b) an antioxidant; (c) a
corrosion inhibitor; (d) an oil of lubricating viscosity; and (e)
optionally an antiwear agent.
2. The method of claim 1, wherein the mechanical device requires a
fluid selected from the group consisting of a working fluid, a
hydraulic fluid, a circulating oil, a turbine oil and mixtures
thereof.
3. The method of claim 1, wherein the mechanical device is a
hydraulic system or a turbine system.
4. The method of claim 1, wherein the dispersant is a borated
dispersant.
5. The method of claim 1, wherein the antioxidant comprises (i) a
hindered phenol or (ii) an alkylated diphenylamine.
6. The method of claim 1, wherein the corrosion inhibitor comprises
(i) a 2,5-bis(alkyl-dithio)-1,3,4-thiadiazole, (ii) a benzotriazole
containing a hydrocarbyl substitution on at least one of the
following ring positions 4- or 5- or 6- or 7-, or (iii) a
benzotriazole containing a hydrocarbyl substitution on at least one
of the following ring positions 1- or 2-.
7. The method of claim 1, wherein the lubricating composition
further comprises (i) a non-ionic phosphorus compound; (ii) an
amine salt of a phosphorus compound; or (iii) an ammonium salt of a
phosphorus compound.
8. The method of claim 1, wherein the lubricating composition
comprises: (a) about 0.01 to about 2 wt % of a dispersant; (b)
about 0.01 to about 2 wt % of an antioxidant; (c) about 0.0001 wt %
to about 0.1 wt % of a corrosion inhibitor; (d) an oil of
lubricating viscosity; and (e) about 0 wt % to about 5 wt % of an
antiwear agent.
9. The method of claim 1, wherein the lubricating composition
further comprises about 0.05 wt % to about 1.5 wt % of an antiwear
agent.
10. An ashless lubricating composition comprising: (a) a
dispersant; (b) an antioxidant; (c) a corrosion inhibitor; (d) an
oil of lubricating viscosity; and (e) optionally an antiwear
agent.
11. The ashless lubricating composition of claim 10 comprising: (a)
about 0.01 to about 2 wt % of a dispersant; (b) about 0.01 to about
2 wt % of an antioxidant; (c) about 0.0001 wt % to about 0.1 wt %
of a corrosion inhibitor; (d) an oil of lubricating viscosity; and
(e) about 0 wt % to about 5 wt % of an antiwear agent.
12. The ashless lubricating composition of claim 11, wherein the
antiwear agent is present at about 0.05 wt % to about 1.5 wt % of
the ashless lubricating composition.
Description
FIELD OF INVENTION
[0001] The present invention relates to a lubricating composition
containing a dispersant, a corrosion inhibitor and an antioxidant.
The invention further provides a method for lubricating a
mechanical device, typically requiring a working fluid, a hydraulic
fluid, a circulating oil or a turbine oil, with the lubricating
composition.
BACKGROUND OF THE INVENTION
[0002] Ash-containing and ashless lubricating compositions are
utilised in various mechanical devices (for example stationary or
mobile machinery requiring a working fluid, a hydraulic fluid, a
circulating oil or a turbine oil). The lubricating compositions
often operate under high temperatures and/or high pressure regimes
in the mechanical device. The high temperatures and/or high
pressure regimes are believed to decompose additives in the
lubricating composition that are less thermally and/or oxidatively
stable. Typically additives that tend to decompose are often
ash-containing additives that contain a metal. Furthermore, as
ash-containing additives decompose, divalent metals such as zinc,
calcium or magnesium, are released into the lubricating
composition. The divalent metals are then capable of reacting with
other performance additives present in the lubricating composition,
such as alkenyl succinic anhydrides and alkenyl succinimides
creating sludge and other particulate matter that can cause filter
plugging.
[0003] In an attempt to overcome the difficulties associated with
lubricating a mechanical device with ash-containing lubricating
compositions, ashless formulations have been contemplated. However,
the formulation of an ashless lubricating composition suitable for
a mechanical device may be difficult and many compositions are
believed to have at least one of limited oxidative stability,
limited thermal stability, filter plugging, and produce
unacceptable levels of sludge.
[0004] EP 0 821 053 A2 discloses a synergistic antioxidant
composition composed of amine salts of alkyl phosphates and
ethylene diamine, ammonium or metal salts of alkylarylsulphonates.
The antioxidant composition is useful for zinc-free antiwear
hydraulic fluids.
[0005] International Application WO 00/11122 discloses lubricating
compositions containing (I) 100 pbw of a base oil, (II) an antiwear
agent comprising (i) from 0.05 to 10 pbw of a phosphorothionate and
from 0.01 to 1.0 pbw of an amine salt of phosphorus compound and/or
(ii) from 0.05 to 10 pbw of a dithiophosphate, and (III) a rust
preventing agent comprising from 0.01 to 1.0 pbw of an amide
obtained by reacting a polyalkylene polyamine and a carboxylic acid
having from 4 to 30 carbon atoms. The lubricating composition is
suitable for hydraulic systems.
[0006] U.S. Pat. No. 5,922,657 discloses a hydraulic fluid
containing a base oil selected from mineral, vegetable and
synthetic oils, .beta.-dithiophosphorylated propionic acid, and at
least one oil additive from the group consisting of antioxidants,
metal passivators, rust inhibitors, dispersants, detergents,
viscosity index improvers, pour point depressants, antifoams, solid
lubricants and further antiwear agents.
[0007] US Patent Application 2002/0010103 A1 discloses industrial
oils such as hydraulic oils containing (a) at least one a compound
selected from the group consisting of a phosphoric acid ester, a
thiophosphoric acid ester, and amine salts thereof; (b) at least
one of a phosphorus acid ester and/or an amine salt thereof; and
(c) at least one compound selected from the group consisting of an
alkenyl succinimide, an alkenyl succinic acid ester, benzylamine,
and derivatives thereof.
[0008] International Application WO 04/113479 discloses industrial
fluids containing (1) an antiwear package comprising: (a) a
hydrocarbyl phosphate and amine salt thereof; and (b) an alkylene
coupled adduct of a hydrocarbyl substituted dithiophosphoric acid
and a .alpha.,.beta.-unsaturated carbonyl containing compound; (2)
an antioxidant package comprising: (a) a hydrocarbyl diphenylamine;
and (b) a sterically hindered phenol; (3) a metal deactivator; and
(4) an oil of lubricating viscosity.
[0009] Hence it would be desirable to discover a lubricating
composition suitable for a mechanical device capable of reducing or
minimising at least one of filter plugging, limited oxidative
stability, limited thermal stability, and produce unacceptable
levels of sludge. The present invention provides a lubricating
composition and method of lubricating a mechanical device capable
of reducing or minimising at least one of filter plugging, limited
oxidative stability, limited thermal stability, and produce
unacceptable levels of sludge.
SUMMARY OF THE INVENTION
[0010] In one embodiment the invention provides an ashless
lubricating composition comprising:
[0011] (a) a dispersant;
[0012] (b) an antioxidant;
[0013] (c) a corrosion inhibitor; and
[0014] (d) an oil of lubricating viscosity.
[0015] In one embodiment the invention provides a method for
lubricating a mechanical device (typically requiring a working
fluid, a hydraulic fluid, a circulating oil or a turbine oil)
comprising supplying to the mechanical device an ashless
lubricating composition comprising:
[0016] (a) a dispersant;
[0017] (b) an antioxidant;
[0018] (c) a corrosion inhibitor; and
[0019] (d) an oil of lubricating viscosity.
[0020] In one embodiment the invention provides an ashless
lubricating composition comprising:
[0021] (a) about 0.01 to about 2 wt % of a dispersant;
[0022] (b) about 0.01 to about 2 wt % of an antioxidant;
[0023] (c) about 0.0001 wt % to about 0.1 wt % of a corrosion
inhibitor; and
[0024] (d) an oil of lubricating viscosity.
[0025] In one embodiment the invention provides a method for
lubricating a mechanical device (typically requiring a working
fluid, a hydraulic fluid, a circulating oil or a turbine oil)
comprising supplying to the mechanical device an ashless
lubricating composition comprising:
[0026] (a) about 0.01 to about 2 wt % of a dispersant;
[0027] (b) about 0.01 to about 2 wt % of an antioxidant;
[0028] (c) about 0.0001 wt % to about 0.1 wt % of a corrosion
inhibitor; and
[0029] (d) an oil of lubricating viscosity.
[0030] In one embodiment the ashless lubricating compositions
disclosed above further comprises an antiwear agent. In one
embodiment the ashless lubricating compositions disclosed above
further contain about 0.05 wt % to about 1.5 wt % of an antiwear
agent.
[0031] In one embodiment the invention provides the ashless
lubricating compositions disclosed above in the form of a
concentrate.
DETAILED DESCRIPTION OF THE INVENTION
[0032] The present invention provides an ashless lubricating
composition and a method for lubricating a mechanical device as
disclosed above.
[0033] As used herein the term "ashless" means that the lubricating
composition and/or additives discussed below are substantially-free
of metal. Substantially-free of means the composition will contain
ash-forming materials (e.g., a metal, typically a divalent metal
such as zinc, calcium or magnesium) at less than about 150 ppm, or
less than about 100 ppm, or about 10 ppm or less, or less than
about 1 ppm. Typically, the ash-forming materials will be present
only in trace amounts, normally associated with contaminants.
Dispersant
[0034] A suitable dispersant includes a succinimide dispersant (for
example N-substituted long chain alkenyl succinimides), a Mannich
dispersant, an ester-containing dispersant, a condensation product
of a fatty hydrocarbyl monocarboxylic acylating agent with an amine
or ammonia, an alkyl amino phenol dispersant, a hydrocarbyl-amine
dispersant, a polyether dispersant, or a polyetheramine dispersant.
In different embodiments the dispersant includes a succinimide
dispersant, succinic acid ester dispersant, or Mannich
dispersant.
[0035] In different embodiments the succinimide dispersant contains
an average of at least about 8, or about 30, or about 35 up to
about 350, or to about 200, or to about 100 carbon atoms. In one
embodiment, the long chain alkenyl group is derived from a
polyalkene characterised by an Mn (number average molecular weight)
of at least 500. Generally, the polyalkene is characterised by an
Mn of about 500, or about 700, (or about 800, or even about 900) to
about 5000, (or to about 2500, or to about 2000, or to about 1500,
or to about 1200). In one embodiment the long chain alkenyl group
includes those derived from polyolefins. The polyolefins may be
derived from monomers including mono-olefins having about 2 to
about 10 carbon atoms, such as ethylene, propylene, 1-butene,
isobutylene, and 1-decene. An especially useful monoolefin source
is a C.sub.4 refinery stream having about 35 to about 75 weight
percent butene content and about 30 to about 60 weight percent
isobutene content. Useful polyolefins include polyisobutylenes
having a number average molecular weight of about 400 to about
5000, or about 400 to about 2500, or about 400, or about 500 to
about 1500. The polyisobutylene vinylidene double bond content in
different embodiments includes the ranges of about 5% to about 69%,
or about 50% to about 69%, or about 50% to about 95%.
[0036] In one embodiment the succinimide dispersant comprises a
polyisobutylene succinimide, wherein the polyisobutylene has a
number average molecular weight of about 400 to about 5000.
[0037] Succinimide dispersants and their methods of preparation are
more fully described in U.S. Pat. Nos. 4,234,435 and 3,172,892.
[0038] Suitable amines include mono amines or polyamines (for
example ethylenediamine, diethylenetriamine, triethylenetetramine,
pentaethylenehexamine, or still bottoms (commercially available
from Dow as HPAX.RTM.)). The hydrocarbyl-substituted amine may be
formed by heating a mixture of a chlorinated olefin or polyolefin
such as a chlorinated polyisobutylene with an amine such as
ethylenediamine in the presence of a base such as sodium carbonate
as described in U.S. Pat. No. 5,407,453.
[0039] The dispersants may also be post-treated by conventional
methods by a reaction with any of a variety of agents. Among these
are boron-containing compounds, urea, thiourea,
dimercaptothiadiazoles, carbon disulphide, aldehydes, ketones,
carboxylic acids, hydrocarbon-substituted succinic anhydrides,
maleic anhydride, nitriles, epoxides, phosphorus compounds and/or
metal compounds. In one embodiment the dispersant is a borated
dispersant. Typically the borated dispersant is derived from a
succinimide dispersant comprising a polyisobutylene succinimide,
wherein the polyisobutylene has a number average molecular weight
of 400 to 5000.
[0040] A borated succinimide dispersant may be prepared using a
borating agent. The borating agent includes various forms of boric
acid (including metaboric acid, HBO.sub.2, orthoboric acid,
H.sub.3BO.sub.3, and tetraboric acid, H.sub.2B.sub.4O.sub.7), boric
oxide, boron trioxide, and alkyl borates, such as those of the
formula (RO).sub.xB(OH).sub.y wherein x is about 1 to about 3 and y
is about 0 to about 2, the sum of x and y being 3, and where R is
an alkyl group containing about 1 to about 6 carbon atoms. In one
embodiment, the boron compound is an alkali or mixed alkali metal
and alkaline earth metal borate. These metal borates are generally
hydrated particulate metal borates which are known in the art. In
one embodiment the metal borates include mixed alkali and alkaline
earth metal borates. The metal borates are available
commercially.
[0041] In different embodiments the dispersant is present in ranges
including about 0.001 wt % to about 5 wt %, or about 0.005 to about
2.5 wt %, about 0.05 to about 1.5 wt %, or about 0.08 to about 0.8
wt % of the lubricating composition.
Antioxidant
[0042] The antioxidant of the invention includes sulphurised
olefins, sulphides such as tert-nonyl mercaptan reacted with
propylene oxide (mole ratio 1:1), a hindered phenol, or aminic
compounds such as phenylalphanaphthylamine or an alkylated
diphenylamine.
[0043] Examples of a suitable hindered phenol include
2,6-di-tert-butyl-4-methylphenol,
3-(3,5-di-tert-butyl-4-hydroxy-phenyl)-propionic acid butyl ester,
3-(3,5-di-tert-butyl-4-hydroxy-phenyl)-propionic acid isooctyl
ester or 3-(3,5-di-tert-butyl-4-hydroxy-phenyl)-propionic acid
2-ethylhexyl ester), 2,6-di-tert-butylphenol,
4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol,
4-propyl-2,6-di-tert-butylphenol, 4-butyl-2,6-di-tert-butylphenol
4-pentyl-2-6-di-tert-butylphenol, 4-hexyl-2,6-di-tert-butylphenol,
4-heptyl-2,6-di-tert-butylphenol,
4-(2-ethylhexyl)-2,6-di-tert-butylphenol,
4-octyl-2,6-di-tert-butylphenol, 4-nonyl-2,6-di-tert-butylphenol,
4-decyl-2,6-di-tert-butylphenol, 4-undecyl-2,6-di-tert-butylphenol,
4-dodecyl-2,6-di-tert-butylphenol,
4-tridecyl-2,6-di-tert-butylphenol,
4-tetradecyl-2,6-di-tert-butylphenol, or mixtures thereof.
[0044] Examples of a suitable methylene-bridged sterically hindered
phenol include 4,4'-methylenebis(6-tert-butyl-o-cresol),
4,4'-methylenebis(2-tert-amyl-o-cresol),
2,2'-methylenebis(4-methyl-6-tert-butylphenol),
4,4'-methylene-bis(2,6-di-tertbutylphenol), or mixtures
thereof.
[0045] Examples of a suitable aminic compound include nonyl
diphenylamine, di-nonyl diphenylamine, octyl diphenylamine,
di-octyl diphenylamine, butyl octyl diphenylamine, octyl styrenyl
diphenylamine or diethyl dinonyl diphenylamine.
[0046] In one embodiment the antioxidant includes (i) a hindered
phenol or (ii) an alkylated diphenylamine. In one embodiment the
antioxidant includes a mixture of a hindered phenol and an
alkylated diphenylamine.
[0047] In different embodiments the antioxidant is present in
ranges including about 0.01 to about 3 wt %, or about 0.01 to about
2 wt %, or about 0.05 to about 1 wt % of the lubricating
composition.
Corrosion Inhibitor
[0048] The corrosion inhibitor may also be described as a metal
deactivator or a yellow-metal passivator.
[0049] Examples of a corrosion inhibitor include benzotriazoles,
1,2,4-triazoles, benzimidazoles, 2-alkyldithiobenzimidazoles,
2-alkyldithiobenzothiazoles,
2-(N,N-dialkyldithiocarbamoyl)benzothiazoles,
2,5-bis(alkyl-dithio)-1,3,4-thiadiazoles,
2,5-bis(N,N-dialkyldithiocarbamoyl)-1,3,4-thiadiazoles,
2-alkyldithio-5-mercapto thiadiazoles or mixtures thereof.
[0050] In one embodiment the corrosion inhibitor includes a
benzotriazole. In one embodiment the corrosion inhibitor includes a
2,5-bis(alkyl-dithio)-1,3,4-thiadiazole.
[0051] Benzotriazoles include those containing hydrocarbyl
substitutions on at least one of the following ring positions 1- or
2- or 4- or 5- or 6- or 7-. The hydrocarbyl groups in different
embodiments contain 1 to about 30, or 1 to about 15, or 1 to about
16 carbon atoms. In one embodiment the corrosion inhibitor includes
tolyltriazole. In one embodiment hydrocarbyl benzotriazoles
substituted at positions 4- or 5- or 6- or 7- are further reacted
with an aldehyde and an amine.
[0052] Examples of suitable hydrocarbyl benzotriazoles further
reacted with an aldehyde and an amine include
N,N-bis(2-ethylhexyl)-ar-methyl-1H-benzotriazole-1-methanamine,
N,N-bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methanamine,
N,N-bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methanamine,
2H-benzotriazole-2-methanamine,
N-(4-methoxyphenyl)-1H-benzotriazole-1-methanamine,
N,N-didodecyl-1H-benzotriazole-1-methanamine,
N-(1H-benzotriazol-1-ylmethyl)-N-(2-ethylhexyl)-1H-benzotriazole-1-methan-
amine, N-methyl-N-phenyl-1H-benzotriazole-1-methanamine,
4,5,6,7-tetrahydro-N,N-ditridecyl-1H-benzotriazole-1-methanamine,
N,N-dioctadecyl-1H-benzotriazole-1-methanamine,
5-methyl-N,N-dioctyl-1H-benzotriazole-1-methanamine,
N,N-dibutyl-1H-benzotriazole-1-methanamine,
N-(4-methylphenyl)-1H-benzotriazole-1-methanamine,
N,N-bis(2-ethylhexyl)-1H-benzotriazole-1-methanamine,
N,N-dioctyl-2H-benzotriazole-2-methanamine,
N-dodecyl-1H-benzotriazole-1-methanamine,
N-phenyl-1H-benzotriazole-1-methanamine,
N,N-didodecyl-4,5,6,7-tetrahydro-1H-benzotriazole-1-methanamine,
N,N-bis(2-ethylhexyl)-5-methyl-1H-benzotriazole-1-methanamine,
N-octadecyl-1H-benzotriazole-1-methanamine,
N,N-didodecyl-2H-benzotriazole-2-methanamine,
N,N-dioctyl-1H-benzotriazole-1-methanamine,
N-(2-ethylhexyl)-1H-benzotriazole-1-methanamine,
4,5,6,7-tetrahydro-N,N-ditetradecyl-1H-benzotriazole-1-methanamine,
or mixtures thereof. In one embodiment the corrosion inhibitor
includes
N,N-bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methanamine or
N,N-bis(2-ethylhexyl)-ar-methyl-1H-benzotriazole-1-methanamine.
[0053] In one embodiment, the corrosion inhibitor includes (i) a
2,5-bis(alkyl-dithio)-1,3,4-thiadiazole, (ii) a benzotriazole
containing a hydrocarbyl substitution on at least one of the
following ring positions 4- or 5- or 6- or 7-, or (iii) a
benzotriazole containing a hydrocarbyl substitution (typically a
benzotriazole further reacted with an aldehyde and an amine) at
least one of the following ring positions 1- or 2-.
[0054] In one embodiment, the corrosion inhibitor includes
2,5-bis(alkyl-dithio)-1,3,4-thiadiazoles. In different embodiments
the alkyl groups of 2,5-bis(alkyl-dithio)-1,3,4-thiadiazoles
contain 1 to about 30, or about 2 to about 25, or 4 to about 20, or
about 6 to about 16 carbon atoms. Examples of suitable
2,5-bis(alkyl-dithio)-1,3,4-thiadiazoles include
2,5-bis(tert-octyldithio)-1,3,4-thiadiazole,
2,5-bis(tert-nonyldithio)-1,3,4-thiadiazole,
2,5-bis(tert-decyldithio)-1,3,4-thiadiazole,
2,5-bis(tert-undecyldithio)-1,3,4-thiadiazole,
2,5-bis(tert-dodecyldithio)-1,3,4-thiadiazole, or mixtures
thereof.
[0055] The corrosion inhibitor may be used alone or in combination
with two, three or more corrosion inhibitors. In one embodiment the
corrosion inhibitor includes a mixture of (i) a
2,5-bis(alkyl-dithio)-1,3,4-thiadiazole, (ii) a benzotriazole
containing a hydrocarbyl substitution on at least one of the
following ring positions 4- or 5- or 6- or 7-, and (iii) a
benzotriazole containing a hydrocarbyl substitution (typically a
benzotriazole further reacted with an aldehyde and an amine) on at
least one of the following ring positions, 1- or 2-.
[0056] In different embodiments the corrosion inhibitor is present
in ranges including about 0.0001 wt % to about 5 wt %, or about
0.0001 wt % to about 0.5 wt %, or about 0.0001 wt % to about 0.1 wt
%, or about 0.0005 wt % to about 0.06 wt % of the lubricating
composition.
Oils of Lubricating Viscosity
[0057] The lubricating composition comprises an oil of lubricating
viscosity. Such oils include natural and synthetic oils, oil
derived from hydrocracking, hydrogenation, and hydrofinishing,
unrefined, refined and re-refined oils and mixtures thereof.
[0058] Unrefined oils are those obtained directly from a natural or
synthetic source generally without (or with little) further
purification treatment.
[0059] Refined oils are similar to the unrefined oils except they
have been further treated in one or more purification steps to
improve one or more properties. Purification techniques are known
in the art and include solvent extraction, secondary distillation,
acid or base extraction, filtration, percolation and the like.
[0060] Re-refined oils are also known as reclaimed or reprocessed
oils, and are obtained by processes similar to those used to obtain
refined oils and often are additionally processed by techniques
directed to removal of spent additives and oil breakdown
products.
[0061] Natural oils useful in making the inventive lubricants
include animal oils, vegetable oils (e.g., castor oil, lard oil),
mineral lubricating oils such as liquid petroleum oils and
solvent-treated or acid-treated mineral lubricating oils of the
paraffinic, naphthenic or mixed paraffinic-naphthenic types and
oils derived from coal or shale or mixtures thereof.
[0062] Synthetic lubricating oils are useful and include
hydrocarbon oils such as polymerised and interpolymerised olefins
(e.g., polybutylenes, polypropylenes, propyleneisobutylene
copolymers); poly(1-hexenes), poly(1-octenes), poly(1-decenes), and
mixtures thereof; alkyl-benzenes (e.g. dodecylbenzenes,
tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)-benzenes);
polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls);
alkylated diphenyl ethers and alkylated diphenyl sulphides and the
derivatives, analogs and homologs thereof or mixtures thereof.
[0063] Other synthetic lubricating oils include polyol esters (such
as Priolube.RTM.3970), diesters, liquid esters of
phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl
phosphate, and the diethyl ester of decane phosphonic acid), or
polymeric tetrahydrofurans. Synthetic oils include those produced
by Fischer-Tropsch reactions and typically may be hydroisomerised
Fischer-Tropsch hydrocarbons or waxes. In one embodiment oils
include those prepared by a Fischer-Tropsch gas-to-liquid synthetic
procedure as well as other gas-to-liquid oils.
[0064] Oils of lubricating viscosity may also be defined as
specified in the American Petroleum Institute (API) Base Oil
Interchangeability Guidelines. The five base oil groups are as
follows: Group I (sulphur content >0.03 wt %, and/or <90 wt %
saturates, viscosity index 80-120); Group II (sulphur content
.ltoreq.0.03 wt %, and .gtoreq.90 wt % saturates, viscosity index
80-120); Group III (sulphur content .ltoreq.0.03 wt %, and
.gtoreq.90 wt % saturates, viscosity index .gtoreq.120); Group IV
(all polyalphaolefins (PAOs)); and Group V (all others not included
in Groups I, II, III, or IV). The oil of lubricating viscosity
comprises an API Group I, Group II, Group III, Group IV, Group V
oil or mixtures thereof. Often the oil of lubricating viscosity is
an API Group I, Group II, Group III, Group IV oil or mixtures
thereof. Alternatively the oil of lubricating viscosity is often an
API Group II, Group III or Group IV oil or mixtures thereof.
[0065] The amount of the oil of lubricating viscosity present is
typically the balance remaining after subtracting from 100 wt % the
sum of the amount of the polymer, the antiwear agent, the corrosion
inhibitor and other performance additives.
[0066] The lubricating composition may be in the form of a
concentrate and/or a fully formulated lubricant. If the dispersant,
the antioxidant and the corrosion inhibitor are in the form of a
concentrate (which may be combined with additional oil to form, in
whole or in part, a finished lubricant), the ratio of the
components (a), (b) and (c) (i.e. the dispersant, the antioxidant
and the corrosion inhibitor to the oil of lubricating viscosity
and/or to diluent oil include the ranges of about 1:99 to about
99:1 by weight, or about 80:20 to about 10:90 by weight.
Other Performance Additives
[0067] The composition of the invention optionally further includes
at least one other performance additive. The other performance
additives include antiwear agents, viscosity index improvers (that
is viscosity modifiers), foam inhibitors, demulsifiers, pour point
depressants, foam inhibitors, a carboxylic acid or anhydride, and
mixtures thereof.
[0068] The total combined amount of the other performance additive
compounds present on an oil free basis may include ranges of 0 wt %
to about 10 wt %, or about 0 wt % to about 5 wt %, or about 0.005
wt % to about 4 wt %, or about 0.05 wt % to about 2.5 wt %, or
about 0.1 wt % to about 1.5 wt % of the composition. Although one
or more of the other performance additives may be present, it is
common for the other performance additives to be present in
different amounts relative to each other.
Antiwear Agent
[0069] In one embodiment the antiwear agent comprises a
phosphorus-containing acid, salt or ester, or mixtures thereof. In
one embodiment the antiwear agent is in the form of a mixture.
[0070] The antiwear agent includes those derived from phosphoric
acid, phosphorous acid, thiophosphoric acid, thiophosphorous acid,
or mixtures thereof.
[0071] In one embodiment the antiwear agent includes (i) a
non-ionic phosphorus compound; (ii) an amine salt of a phosphorus
compound; or (iii) an ammonium salt of a phosphorus compound.
[0072] In one embodiment the antiwear agent comprises an ammonium
or amine salt of a phosphorus-containing acid or ester.
[0073] The amine salt of a phosphorus acid or ester includes
phosphoric acid esters and amine salts thereof;
dialkyldithiophosphoric acid esters and amine salts thereof; amine
salts of phosphites; and amine salts of phosphorus-containing
carboxylic esters, ethers, and amides; and mixtures thereof.
[0074] The amine salt of a phosphorus acid or ester may be used
alone or in combination.
[0075] In one embodiment the amine salt of a phosphorus acid or
ester includes a partial amine salt, or a partial amine-metal salt
compound or mixtures thereof. In one embodiment the amine salt of a
phosphorus acid or ester further contains a sulphur atom in the
molecule.
[0076] The amine salt may be prepared from amines that include
primary amines, secondary amines, tertiary amines, and mixtures
thereof. The amines include those with at least one hydrocarbyl
group, or, in certain embodiments, two or three hydrocarbyl groups.
In different embodiments the hydrocarbyl groups contain about 2 to
about 30, or about 8 to about 26, or about 10 to about 20, or about
13 to about 19 carbon atoms.
[0077] Primary amines include ethylamine, propylamine, butylamine,
2-ethylhexylamine, octylamine, and dodecylamine, as well as such
fatty amines as n-octylamine, n-decylamine, n-dodecylamine,
n-tetradecylamine, n-hexadecylamine, n-octadecylamine and
oleyamine. Other useful fatty amines include commercially available
fatty amines such as "Armeen.RTM." amines (products available from
Akzo Chemicals, Chicago, Ill.), such as Armeen C, Armeen O, Armeen
OL, Armeen T, Armeen HT, Armeen S and Armeen SD, wherein the letter
designation relates to the fatty group, such as coco, oleyl,
tallow, or stearyl groups.
[0078] Examples of suitable secondary amines include dimethylamine,
diethylamine, dipropylamine, dibutylamine, diamylamine,
dihexylamine, diheptylamine, methylethylamine, ethylbutylamine and
ethylamylamine. The secondary amines also include cyclic amines
such as piperidine, piperazine and morpholine.
[0079] The amine may also be a tertiary-aliphatic primary amine.
The aliphatic group on the tertiary-aliphatic primary amine in
different embodiments contains about 4 to about 30, or about 6 to
about 26, or about 8 to about 24 carbon atoms. Tertiary alkyl
amines include monoamines such as tert-butylamine, tert-hexylamine,
1-methyl-1-amino-cyclohexane, tert-octylamine, tert-decylamine,
tertdodecylamine, tert-tetradecylamine, tert-hexadecylamine,
tert-octadecylamine, tert-tetracosanylamine, and
tert-octacosanylamine.
[0080] In one embodiment the amine salt of a phosphorus acid or
ester includes an amine with about C.sub.11 to about C.sub.14
tertiary alkyl primary groups or mixtures thereof. In one
embodiment the amine salt of a phosphorus compound includes an
amine with about C.sub.14 to about C.sub.18 tertiary alkyl primary
amines or mixtures thereof. In one embodiment the amine salt of a
phosphorus compound includes an amine with about C.sub.18 to about
C.sub.22 tertiary alkyl primary amines or mixtures thereof.
[0081] Mixtures of amines may also be used in the invention. In one
embodiment a useful mixture of amines is "Primene.RTM. 81R" and
"Primene.RTM. JMT." Primene.RTM. 81R and Primene.RTM. JMT (both
produced and sold by Rohm & Haas) are mixtures of C.sub.11 to
C.sub.14 tertiary alkyl primary amines and C.sub.18 to C.sub.22
tertiary alkyl primary amines respectively.
[0082] In one embodiment the amine salt of a phosphorus acid or
ester is the reaction product of a C.sub.14 to C.sub.18 alkylated
phosphoric acid with Primene.RTM. 81R (produced and sold by Rohm
& Haas) which is a mixture of C.sub.11 to C.sub.14 tertiary
alkyl primary amines.
[0083] Examples of the amine salt of a phosphorus acid or ester
include the reaction product(s) of isopropyl, methyl-amyl
(1,3-dimethylbutyl or mixtures thereof), 2-ethylhexyl, heptyl,
octyl, nonyl, decyl, dodecyl, butadecyl, hexadecyl, octadecyl or
eicosyl phosphoric (or dithiophosphoric) acids with ethylene
diamine, morpholine, 2-ethylhexyl amine or Primene.RTM. 81R, and
mixtures thereof. In one embodiment the antiwear agent comprises an
amine salt of a phosphorus acid or ester or mixtures thereof. In
one embodiment the phosphorus acid or ester is a
C.sub.14-C.sub.18-alkyl phosphorus acid or ester with Primene.RTM.
81R or 2-ethylhexyl amine.
[0084] In one embodiment the dithiophosphoric acids include those
reacted with an epoxide or a glycol. This reaction product is
further reacted with a phosphorus acid, anhydride, or lower ester.
The epoxide includes an aliphatic epoxide or a styrene oxide.
Examples of useful epoxides include ethylene oxide, propylene
oxide, butene oxide, octene oxide, dodecene oxide, styrene oxide
and the like. In one embodiment the epoxide is propylene oxide. The
glycols include aliphatic glycols, wherein the aliphatic groups of
the glycols in different embodiments have about 2 to about 12, or
about 2 to about 6, or about 2 to about 3 carbon atoms. The
dithiophosphoric acids, glycols, epoxides, inorganic phosphorus
reagents and methods of reacting the same, are described in U.S.
Pat. Nos. 3,197,405 and 3,544,465. The resulting acids may then be
salted with amines. An example of a suitable dithiophosphoric acid
is prepared by adding phosphorus pentoxide (about 64 grams) at
about 58.degree. C. over a period of about 45 minutes to about 514
grams of hydroxypropyl O,O'-di(1,3-dimethylbutyl)phosphorodithioate
(prepared by reacting di(1,3-dimethylbutyl)-phosphorodithioic acid
with about 1.3 moles of propylene oxide at about 25.degree. C.).
The mixture is heated at about 75.degree. C. for about 2.5 hours,
mixed with diatomaceous earth and filtered at about 70.degree. C.
The filtrate contains about 11.8% by weight phosphorus, about 15.2%
by weight sulphur, and has an acid number of about 87 (bromophenol
blue).
[0085] In one embodiment the antiwear agent comprises an
amide-containing dithiophosphorus acid ester. A more detailed
description for the amide-containing dithiophosphorus acid ester is
found in U.S. Pat. No. 4,938,884. A description of the molecular
structure is found in column 2, lines 4 to 28. Suitable examples
prepared are disclosed in Examples 1 to 7 (column 8, line 45 to
column 10, line 13 of U.S. Pat. No. 4,938,884). Typically the
amide-containing dithiophosphorus acid ester is prepared by the
addition of dithiophosphoric acid to an acrylamide, such as
acrylamide, methacrylamide, methylenebisacrylamide, or
methylenebismethacrylamide. In one embodiment the amide-containing
dithiophosphorus acid ester includes a methylenebisacrylamide, or
methylenebismethacrylamide product prepared from prepared by the
addition of a dithiophosphoric acid to acrylamide to form an
adduct; and subsequent reaction of the adduct with formaldehyde to
make the methylene coupled product.
[0086] In one embodiment the antiwear agent comprises a carboxylic
acid-containing dithiophosphorus acid ester, for example
3-(bis-pentoxy-thiophosphorylsulphanyl)-propionic acid methyl
ester, 3-(dibutoxy-thiophosphorylsulphanyl)-propionic acid methyl
ester, or mixtures thereof.
[0087] In one embodiment the antiwear agent comprises a non-ionic
phosphorus compound. Typically the phosphorus atom in the non-ionic
phosphorus compound may have an oxidation state of +3 or +5. The
different embodiments comprise phosphite ester, phosphate esters,
or mixtures thereof.
[0088] In one embodiment the antiwear agent includes a non-ionic
phosphorus compound that is a hydrocarbyl phosphite. The
hydrocarbyl-substituted phosphite of the invention includes those
represented by the formula:
##STR00001##
wherein each R''' independently is hydrogen or a hydrocarbyl group,
with the proviso that at least one of the R''' groups is
hydrocarbyl.
[0089] Each hydrocarbyl group of R''' in different embodiments
contains at least about 2, or at least about 4 carbon atoms.
Typically, the combined total sum of carbon atoms present on both
R''' groups is less than about 45, or is less than about 35, or is
less than about 25. Examples of suitable ranges for the number of
carbon atoms present on R''' groups include about 2 to about 40,
about 3 to about 24, or about 4 to about 20. Examples of suitable
hydrocarbyl groups include propyl, butyl, t-butyl, pentyl, hexyl,
dodecyl, butadecyl, hexadecyl, or octadecyl groups. Generally the
hydrocarbyl phosphite is soluble or at least dispersible in oil. In
one embodiment the hydrocarbyl phosphite is di-butyl hydrogen
phosphite or a C.sub.16-18 alkyl or di-alkyl hydrogen phosphite. A
more detailed description of the non-ionic phosphorus compound is
included in column 9, line 48 to column 11, line 8 of U.S. Pat. No.
6,103,673.
[0090] In one embodiment the antiwear agent includes a phosphate
ester. Examples of a suitable phosphate ester include triaryl
phosphates such as tricresyl phosphate, triphenyl phosphate,
tri-dimethylphenyl phosphate, tri-butylphenyl phosphate, or
mixtures thereof.
[0091] In one embodiment the antiwear agent includes a
thiophosphate ester. Examples of a suitable thiophosphate ester
include triaryl thiophosphates such as tricresyl thiophosphate,
triphenyl thiophosphate, tri-dimethylphenyl thiophosphate,
tri-butylphenyl thiophosphate, or mixtures thereof.
[0092] In different embodiments the antiwear agent is present in
ranges including about 0 wt % to about 5 wt %, or about 0.001 wt %
to about 2 wt %, or about 0.05 wt % to about 1.5 wt %, or about 0.1
wt % to about 1 wt % of the lubricating composition.
Viscosity Modifiers
[0093] Viscosity modifiers include hydrogenated copolymers of
styrene-butadiene, ethylene-propylene copolymers, polyisobutenes,
hydrogenated styrene-isoprene copolymers, hydrogenated isoprene
polymers, polymethacrylate, polyacrylate, polyalkyl styrenes,
hydrogenated alkenyl aryl conjugated diene copolymers, polyolefins,
and esters of maleic anhydride-styrene copolymers.
[0094] Other performance additives such as foam inhibitors
including copolymers of ethyl acrylate and 2-ethylhexylacrylate and
optionally vinyl acetate; demulsifiers including trialkyl
phosphates, polyethylene glycols, polyethylene oxides,
polypropylene oxides and (ethylene oxide-propylene oxide) polymers;
pour point depressants including esters of maleic anhydride-styrene
copolymers, polymethacrylates, polyacrylates or polyacrylamides;
and seal swell agents including Exxon Necton-37.TM. (FN 1380) and
Exxon Mineral Seal Oil (FN 3200); and dispersant viscosity
modifiers (often referred to as DVM) include functionalised
polyolefins, for example, ethylene-propylene copolymers that have
been functionalized with the reaction product of maleic anhydride
and an amine, a polymethacrylate functionalised with an amine, or
styrene-maleic anhydride copolymers reacted with an amine; may also
be used in the composition of the invention.
INDUSTRIAL APPLICATION
[0095] The method of the invention is useful for lubricating a
mechanical device typically requiring a working fluid, a hydraulic
fluid, a circulating oil or a turbine oil.
[0096] In one embodiment the mechanical device requires a fluid
selected from the group consisting of a working fluid, a hydraulic
fluid, a circulating oil, a turbine oil and mixtures thereof.
[0097] In different embodiments the mechanical device is a
hydraulic system, a turbine system, or a circulating oil
system.
[0098] The following examples provide illustrations of the
invention. These examples are non exhaustive and are not intended
to limit the scope of the invention.
Examples
Lubricating Compositions EX1 to EX5
[0099] A series of lubricating compositions are prepared containing
the following additives: a borated dispersant, an amine salt of a
phosphorus compound, a mixture of phenolic and aminic antioxidants,
two or more corrosion inhibitors, and antifoam agents. The combined
total treat-rate of all the additives (on an oil-free basis, i.e.
excluding normal amount of diluent oil commonly associated with
each additive) is about 1.47 wt % for Example 1 (EX1), about 1.48
wt % for Example 2 (EX2), about 1.76 wt % for Example 3 (EX3),
about 1.40 wt % for Example 4 (EX4) and about 1.27 wt % for Example
(EX5).
[0100] Examples EX1 to EX5 are evaluated in the following tests:
(i) oxidation stability of steam turbine oils using ASTM Method
D2272, (ii) kinematic viscosity at about 40.degree. C. using ASTM
method D445, and (iii) thermal stability of hydraulic fluids after
heat stressing of the fluid utilising the "Cincinnati Machine
Thermal Stability Test" Procedure A. The Cincinnati Machine Thermal
Stability Test evaluates steel and copper corrosion and thermal
stability.
[0101] The data obtained for tests (i) and (ii) are shown in Table
1. The data obtained for test (iii) are shown in Table 2.
TABLE-US-00001 TABLE 1 Test (ASTM Method) EX1 EX2 EX3 EX4 EX5 D2272
(minutes) 211 222 248 215 268 D445 (mm.sup.2/s) 32.74 32.75 32.95
32.85 32.84
TABLE-US-00002 TABLE 2 Cincinnati Machine Thermal Stability Test
EX1 EX2 EX3 EX4 EX5 Copper Rating 3 3 3 4 5 Copper weight loss (mg)
0.7 1.2 0.2 -2.7 0 Steel Rating 1 1 1 1 1 Steel weight loss (mg)
0.2 0.4 0.1 0 0.3 Sludge Formed (mg/100 ml of oil) 0.95 11 0.65 0.6
3.6
[0102] The data obtained indicate that the lubricating compositions
of the invention are capable of providing a hydraulic fluid,
turbine oil or circulating oil with at least one of acceptable
sludge performance, acceptable thermal stability and acceptable
oxidation stability.
[0103] While the invention has been explained in relation to its
various embodiments, it is to be understood that various
modifications thereof will become apparent to those skilled in the
art upon reading the specification. Therefore, it is to be
understood that the invention disclosed herein is intended to cover
such modifications as fall within the scope of the appended
claims.
* * * * *