Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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LOW SULFUR, LOW ASH, AND LOW PHOSPHORUS LUBRICANT ADDITIVE
PACKAGE USING AN ALKYLAMiNE SALT OF A
DIALKYLMONOTH1OPHOSPHATE
TECHNICAL FIELD OF THE INVENTION
(0001]The present invention relates to lubricating oil compositions, their
method of
preparation, and use. More specifically, this invention relates to an oil
soluble
lubricating additive package to achieve low sulfur, low ash, and low
phosphorus
levels in fully formulated oil.
BACKGROUND OF THE INVENTION
[0002]Combustion engines generate emissions that can pollute our environment.
in
response to increasing regulation and environmental concerns, engine
manufacturers have recognized the need to reduce engine emissions. In an
effort to
reduce emissions in exhaust gases, manufacturers have used particulate traps
and
catalytic converters. However, the lubricating oil used in the engine is
oftentimes
detrimental to devices such as catalytic converters or particulate traps. For
example,
phosphorus present in the lubricating oil is believed to interfere with
catalytic
efficiency. Further, it is believed that sulfur present in the lubricating
oil, after
oxidation and neutralization, may form sulfates that plug exhaust gas traps
thereby
preventing them from oxidizing and burning off trapped organic particulate
matter.
Accordingly, engine manufacturers are requiring lubricating oils that have
lower and
lower sulfur, ash, and phosphorus levels.
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SUMMARY OF THE INVENTION
[0003]An object of the present invention is to provide an oil soluble
lubricating
additive package that can be used to formulate a low sulfur, low ash, and low
phosphorus content oil for use in either gasoline or diesel engines. Further,
a
second object of the present invention is to provide lubricating oils that
contain
minimal sulfur, ash, and phosphorus levels.
[0004]Additionally, another goal of the present invention is to provide a
method for
lubricating the moving parts of a machine.
[0005]The present invention provides for an oil soluble lubricant additive
package
comprising (1 ) at least one alkylamine salt of a dialkylmonothiophosphate,
and (2) at
least one detergent, wherein the weight ratio of the alkyfamine salt of a
dialkylmonothiophosphate to the detergent is from about 0.05:1 to about 3: 7.
[0006] In an embodiment the oil soluble lubricant additive package of the
present
invention has a sulfur content and a phosphorus content sufficient to yield a
lubricating oil having a sulfur content less than about 0.3 wt% and a
phosphorus
content of less than about 0.11 wt%.
j0007] !n an embodiment at least one of the at least one detergent is selected
from
the group consisting of calcium sulfonate, magnesium sulfonate, sodium
sulfonate,
non-sulfurized Mannich phenates, sulfurized phenates, salicylates, overbased
salicylates, saligenin, overbased saligenin, overbased carboxylic acids, and
combinations thereof.
[0008]The present invention additionally includes a lubricating oil comprising
the
inventive oil soluble lubricant additive package, having a total base number
of less
than about 10, and at feast one property selected from fihe group consisting
of: a
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sulfur content less than about 0.3 wt%, a phosphorus content of less than
about 0.11
wt%, and an ash content less than about 1.2 wt%.
[0009]The present invention additionally includes machines lubricated by the
lubricating oil described above. Although the machine may be any machine for
which the inventive lubricating oil would provide satisfactory lubrication, it
is
envisioned that such machinery would include gas engines, diesel engines,
turbine
engines, automatic transmissions, manual transmissions, hypoid axles, and gear
boxes. Furthermore, the present invention includes vehicles comprising the
inventive oil soluble lubricant additive package described above.
[0010]The present invention also includes a method for lubricating an engine
crankcase comprising the step of: at least partially filling the crankcase
with a
lubricant comprising the oil soluble lubricant additive package described
above.
[0011] Further, the present invention provides a method far lubricating moving
parts
of a machine comprising the step of: contacting at least one moving part with
a
lubricant comprising the oil salable lubricant additive package described
above.
Although the method may be successfully employed on a wide variety of
machines, it
is envisioned that such machinery would include: gas engines, diesel engines,
turbine engines, automatic transmissions, manual transmissions, hypoid axles,
and
gear boxes.
[0012]The present invention provides a second inventive oil soluble lubricant
additive package comprising: (1) at least one alkylamine salt of a
dialkylmonothiophosphate and (2) at least one dispersant, wherein the weight
ratio of
the alkylamine salt of a dialkylmonothiophosphate to the dispersant is from
about 1:4
to about 1:20.
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(0013] In another embodiment the oil soluble lubricant additive package
described
above has a sulfur content and a phosphorus content sufficient to yield a
lubricating
oil having a sulfur content less than about 0.3 wt% and a phosphorus content
of less
than about 0.11 wt%.
(0014] ft is also useful herein that at least one dispersant used in the oil
soluble
lubricant additive package described above has a molecular weight of from
about
1,000 to about 20,000 amu. In one embodiment the at least one dispersant is a
malefic anhydride functionalized polyisobutylene polymer that has been reacted
with
a polyamine. Also the at least one dispersant can be a product of a Mannich
reaction. It is further equally possible that the at least one dispersant is
an ethylene-
propylene type dispersant.
(0015] It is further preferred in one embodiment that the oil soluble
lubricant additive
package described above additionally comprise at least one component selected
from the group consisting of: viscosity index improvers and pour point
depressants.
[0016] It is additionally useful herein that a lubricating oil comprising the
oil soluble
lubricant additive package described above has a total base number of less
than
about 10, and at least one property selected from the group consisting of: a
sulfur
content less than about 0.3 wt%, a phosphorus content of less than about 0.11
wt%,
and an ash content less than about 1.2 wt%. In one embodiment the ash content
of
the lubricating oil is less than about 1.0 wt% and in another embodiment is
less than
about 0.8 wt%.
(0017]The present invention also includes machines lubriicated by the
lubricating oil
described above. Although the inventive lubricating oil can be used on a wide
variety of machines, it is envisioned that the machines especially suited for
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lubrication include: gas engines, diesel engines, turbine engines, automatic
transmissions, manual transmissions, hypoid axles, and gear boxes.
[0018]Additionally, the present invention includes vehicles comprising the oil
soluble
lubricant additive package described above.
[0019]The present invention additionally includes a method for lubricating an
engine
crankcase comprising the step of: at least partially filling the crankcase
with a
lubricant comprising the oil soluble Lubricant additive package described
above.
[0020]A method for lubricating moving parts of a machine is also provided
comprising the step of: contacting at (east one moving part with a lubricant
comprising the oil soluble lubricant additive package described above.
Although the
method may be employed with a wide variety of machines, it is believed that
the
method is especially suited for use with: gas engines, diesel engines, turbine
engines, automatic transmissions, manual transmissions, hypoid axles, and gear
boxes.
[0021]The present invention additionally provides for an oil soluble
lubricating
additive package comprising: (1 ) at least one alkylamine salt of a
dialkylmonothiophosphate; and (2) at least one antioxidant, wherein the weight
ratio
of the alkylamine salt of a dialkylmonothiophosphate to antioxidant is from
about
10:1 to about 1:5.
[0022] It is preferred that the oil soluble lubricant additive package has a
sulfur
content and a phosphorus content sufficient to yield a lubricating oil having
a sulfur
content less than about 0.3 wt% and a phosphorus content of less than about
0.11
wt% .
[0023] It is preferred that at least one antioxidant used in the oil soluble
lubricant
additive package of the present invention is selected from the group
consisting of:
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alkylated diphenylamines, sulfurized olefins, phenols, hindered phenols, and
sulfurized phenols.
[0024]The present invention also provides for a lubricating oil comprising the
oil
soluble lubricant additive package described above, having a total base number
of
less than about 10, and at least one property selected from the group
consisting of: a
sulfur content less than about 0.3 wt%, a phosphorus content of less than
about 0.11
wt%, and an ash content less than about 1.2 wt%. In one embodiment the ash
content of the lubricating oil is less than about 1.0 wt% arid in another
embodiment is
less than about 0.8 wt%.
[0025] The present invention also includes machines lubricated by the
lubricating oil
described above. Although a wide variety of machines may be lubricated by the
present inventive lubricating oil, it is preferred that the machine is
selected from the
group consisting of: gas engines, diesel engines, turbine engines, automatic
transmissions, manual transmissions, hypoid axles, and gear boxes.
[0026] Additionally, the present invention includes vehicles comprising the
oil soluble
lubricant additive package described above.
[0027] The present invention also includes a method for lubricating an engine
crankcase comprising the step of: at least partially filling the crankcase
with a
lubricant comprising the oil soluble lubricant additive package described
above.
[0028]The present invention additionally provides a method for lubricating
moving
parts of a machine comprising the step of: contacting at least one moving part
with a
lubricant comprising the oil soluble lubricant additive package described
above. It is
envisioned that this method may be employed with a wide variety of machines
including: gas engines, diesel engines, turbine engines, automatic
transmissions,
manual transmissions, hypoid axles, and gear boxes.
6
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[0029] The present invention additionally provides yet another oil soluble
lubricant
additive package comprising: (1 ) at least one alkylamine salt of a
dialkylmonothiophosphate; (2) and at least one component selected from the
group
consisting of: detergents, dispersants, antioxidants, friction modifiers,
viscosity index
improvers, and pour point depressants.
[0030] It is preferred that the oil soluble lubricant additive package
described above
has at least one property selected from the group consisting of: a sulfur
content less
than about 3 wt% and a phosphorus content less than about 1.2 wt%.
[0031] It is preferred that the oil soluble lubricant additive package is
essentially free
of non-sulfurized Mannich phenate.
[0032] It is further preferred that a lubricating oil comprising the oil
soluble lubricant
additive package described above, has a total base number of less than about
10
mg KOH/g, and at least one property selected from the group consisting of: a
sulfur
content less than about 0.3 wt%, a phosphorus content of less than about 0.11
wt%,
and an ash content less than about 1.2 wt%. In one embodiment the ash content
of
the lubricating oil is less than about 1.0 wt% and in another embodiment is
less than
about 0.8 wt%.
[0033]The present invention includes machines Lubricated by the lubricating
oi!
described above. Although it is envisioned that a wide variety of machines may
be
lubricated by the inventive lubricating oil described herein, it is preferred
that the
machines is selected from the group consisting of: gas engines, diesel
engines,
turbine engines, automatic transmissions, manual transmissions, hypoid axles,
and
gear boxes.
[0034]The present invention also includes vehicles comprising the oil soluble
lubricating additive package described herein.
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[0035]The present invention also provides a method for lubricating an engine
crankcase comprising the step of: at least partially filling the crankcase
with a
lubricant comprising the oil soluble lubricant additive package described
above.
[0036] The present invention additionally provides a method for lubricating
the
moving parts of a machine comprising the step of: conta~aing at least one
moving
part with a lubricant comprising the oil soluble lubricant additive package
described
above.
[0037] The present invention also provides a method of achieving a low sulfur,
low
ash, and low phosphate oil formulation comprising: (1) providing an oil
soluble
lubricant additive package comprising an alkylamine salt of a
dialkylmonothiophosphate; and (2) admixing the oil soluble lubricant additive
package with at least a base oil so as to form a lubricating oil having a
total base
number of less than about 10, and at feast one property selected from the
group
consisting of: a sulfur content less than about 0.3 wt%, a phosphorus content
of less
than about 0.11 wt%, and an ash content less than about 1.2 wt%. fn one
embodiment the ash content of the lubricating oil is less than about 1.0 wt%
and in
another embodiment is less than about 0.8 wt%.
[0038 It is preferred that the lubricating oil additionally comprises at least
one
additive selected from the group consisting of: detergents, dispersants,
antioxidants,
friction modifiers, viscosity index improvers, and pour point depressants.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS)
[0039] In accordance with the foregoing summary, the following presents a
detailed
description of the preferred embodiment of the invention that is currently
considered
to be the best mode.
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[0040] We begin with a discussion of the various components employed in the
present invention. Then we shall present an example of an oil formulation
based
upon the oil soluble additive package of the present invention. finally, we
conclude
with a comparison of an inventive oil formulation against a control
formulation in the
CAT 1 N engine test.
BASE OIL
[0041]The base oils useful herein include natural lubricating oils, synthetic
lubricating oils and mixtures thereof. Suitable lubricating oils also include
basestocks obtained by isomerization of synthetic wax and slack wax, as well
as
basestocks produced by hydrocracking the aromatic and polar components of the
crude. In general, both the natural and synthetic lubricating oils will each
have a
kinematic viscosity ranging from about 1 to about 40 mm~Zls (cSt) at
100° C, although
typical applications will reguire each of the base oils to have a viscosity
ranging from
about 1 to about 12, preferably 2 to 8, mm2ls (cSt) at 100° C.
[0042] Natural lubricating oils include animal oils, vegetable oils (e.g.,
castor oil and
lard oil), petroleum oils, mineral oils, and oils derived from coal or shale.
The
preferred natural lubricating oil is mineral oil.
[0043] The mineral oils useful in this invention can include but are not
limited to all
common mineral oil base stocks. This would include oils that are naphthenic or
paraffinic in chemical structure. Oils that are refined by conventional
methodology
using acid, alkali, and clay or other agents such as aluminum chloride, or be
extracted oils produced, for example, by solvent extraction with solvents such
as
phenol, sulfur dioxide, furfural, dichlorodiethyl ether, etc. They may be
hydrotreated
or hydrorefined, dewaxed by chilling or catalytic dewaxing processes, or
hydrocracked. The mineral oil may be produced from natural crude sources or be
9
n ._. _
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composed of isomerized wax materials or residues of other refining processes.
In
one embodiment, the oil of lubricating viscosity is a hydrotreated,
hydrocracked
and/or iso-dewaxed mineral oil having a Viscosity Index (VI) of greater than
80,
preferably greater than 90; greater than 90 volume % saturates and less than
0.03
wt. % sulfur.
[0044] Group li and Group Ill basestocks are also particularly suitable for
use in the
present invention, and are typically prepared from conventional feedstocks
using a
severe hydrogenation step to reduce the aromatic, sulfur and nitrogen content,
followed by dewaxing, hydrofinishing, extraction andlor distillation steps to
produce the
finished base oil. Group If and III basestocks differ from conventional
solvent refined
Group I basestocks in that their sulfur, nitrogen and aromatic contents are
very low.
As a result, these base oils are compositionally very different from
conventional
solvent refined basestocks. The American Petroleum Institute has categorized
these
different basestock types as follows: Group !, >0.03 wt. % sulfur, andJor <90
vol%
saturates, viscosity index between 80 and 120; Group II, < 0.03 wt. % sulfur,
and > 90
vol% saturates, viscosity index between 80 and 120; Group III, < 0.03 wt. %
sulfur,
and > 90 vol% saturates, viscosity index > 120; Group IV, poly-alpha-olefins.
Hydrotreated basestocks and catalytically dewaxed basestocks, because of their
low
sulfur and aromatics content, generally fall into the Group II and Group III
categories.
[0045]There is no limitation as to the chemical composition of the various
basestocks
used in the present invention. For example, the proportions of aromatics,
paraffinics,
and naphthenics in the various Group I, Group ii and Group lil oils can vary
substantially. The degree of refining and the source of the crude used to
produce the
oil generally determine this composition. fn one embodiment, the base oil
comprises
a mineral oil having a VI of at least 110.
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[0046]The lubricating oils may be derived from refined, re-refined oils, or
mixtures
thereof. Unrefined oils are obtained directly from a natural source or
synthetic
source (e.g., coal, shale, or tar sands bitumen) without further purification
or
treatment. Examples of unrefined oils include shale oil obtained directly from
a
retorting operation, petroleum oil obtained directly from diistillation, or an
ester oil
obtained directly from an esterification process, each of which is then used
without
further treatment. Refined oils are similar to the unrefined oils except that
refined
oils have been treated in one or more purification steps to improve one or
more
properties. Suitable purification techniques include distillation,
hydrotreating,
dewaxing, solvent extraction, acid or base extraction, filtration, and
percolation, all of
which are known to those skilled in the art. Re-refined oils are obtained by
treating
used oils in processes similar to those used to obtain the refined oils. These
re-
refined oils are also known as reclaimed or reprocessed oils and are often
additionally processed by techniques for removal of spent additives and oil
breakdown products.
[0047] Synthetic lubricating oils include hydrocarbon oils and halo-
substituted
hydrocarbon oils such as oligomerized, polymerized, and interpolymerized
olefins;
alkylbenzenes; polyphenyls; and alkylated diphenyl ethers, alkylated Biphenyl
sulfides, as well as their derivatives, analogs, and homologs thereof, and the
like.
Preferred synthetic oils are oligomers of a-olefins, particularly oligomers of
1-decene,
having a viscosity ranging from about 1 to about 12, preferably 2 to 8, mm2/s
(cSt) at
100° C. These oligomers are known as poly-a olefins or PAOs.
[0048] Synthetic lubricating oils also include alkylene oxide polymers,
interpolymers,
copolymers, and derivatives thereof where the terminal hydroxyl groups have
been
modified by esterification, etherification, etc. This class of synthetic oils
is
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exemplified by polyoxyatkylene polymers prepared by polymerization of ethylene
oxide or propylene oxide; the alkyl and aryl ethers of these polyoxyalkylene
polymers
(e.g., methyl-polyisopropylene glycol ether having an average molecular weight
of
1000, diphenyl ether of polypropylene glycol having a molecular weight of 100-
1500);
and mono- and poly-carboxylic esters thereof (e.g., the acetic acid esters,
mixed C3-
C8 fatty acid esters, and C~2 oxo acid diester of tetraethylene glycol).
(0049]Another suitable class of synthetic lubricating oils comprises the
esters of
dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids
and alkenyl
succinic acids, malefic acid, azelaic acid, subric acid, sebasic acid, fumaric
acid,
adipic acid, linoleic acid dimer, malonic acid, alkylmalonic acids, alkenyl
malonic
acids, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol,
dodecyl
alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoethers,
propylene glycol, etc.). Specific examples of these esters include dibutyl
adipate,
di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl
azelate,
diisodecyl azelate, dioctyl isothalate, didecyl phthalate, dieicosyl sebacate,
the 2-
ethylhexyl diester of linoleic acid dimer, and the complex ester formed by
reacting
one mole of sebasic acid with two moles of tetraethylene glycol and two moles
of 2-
ethyl-hexanoic acid, and the like. A preferred type of oil from this class of
synthetic
oils is adipates of C4 to C~2 alcohols.
(0050] Esters useful as synthetic lubricating oils also include those made
from C5 to
C~2 monocarboxylic acids and polyols and polyol ethers such as neopentyl
glycol,
trimethylolpropane pentaeythritol, dipentaerythritol, tripentaerythritol, and
the like.
(0051 Silicon-based oils (such as the polyalkyl-, polyaryl-, polyalkoxy-, or
polyaryloxy-siloxane oils and silicate oils) comprise another useful class of
synthetic
lubricating oils. These oils include tetra-ethyl silicate, tetra-isopropyl
silicate, tetra-(2-
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ethylhexyl) silicate, tetra-(4-methyl-2-ethylhexyl) silicate, tetra-(p-tent-
butylphenyl)
silicate, hexa-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes and
poly
(methylphenyl) siloxanes, and the like. Other synthetic lubricating oils
include liquid
esters of phosphorus containing acids (e.g., tricresyl phosphate,
trioctylphosphate,
and diethyl ester of decylphosphonic acid), polymeric tetra-hydrofurans, poly-
alpha-
olefins, and the like.
VISCCOSITY INDEX IMPROVE~RS
[0052] Viscosity index improvers impart high and low temperature operability
to the
lubricating oil and permit it to remain relatively viscous at elevated
temperatures and
also exhibit acceptable viscosity or fluidity at low temperatures. Viscosity
index
improvers are generally high molecular weight hydrocarbon polymers including
polyesters. The viscosity index improvers may also be derivatized to include
other
properties or functions, such as the addition of dispersancy properties. These
oil
soluble viscosity modifying polymers will generally have number average
molecular
weights of from 103 to 106, preferably 104 to 106, as determined by get
permeation
chromatography or osmometry.
[0053]The viscosity index improvers useful herein can include polymethacrylate-
based ones, olefin copolymer-based ones, {e.g., isobutylene-based and ethylene-
propylene copolymer based ones), polyalkyl styrene-based ones, hydrogenated
styrene-butadiene copolymer-based ones, and styrene-malefic anhydride ester
copolymer-based ones.
[0054] Representative examples of suitable viscosity index improvers are found
in
U.S. Pat. Nos. 5,075,383; 5,102,566; 5,139,688; 5,238,588; and 6,107,257. The
above references are incorporated herein by reference.
13
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POUR POINT DEPRESSANTS
[0055] Pour point depressants are used to improve low temperature properties
of oil-
based compositions. See, for example, page 8 of "Lubricant Additives" by C.V.
Smalheer and R. Kennedy Smith (Lezius Hiles Co. publishers, Cleveland, Ohio,
1967). Examples of useful pour point depressants are polymethacrylates;
polyacrylates; polyacrylarnides; condensation products of haloparaffin waxes
and
aromatic compounds; vinyl carboxylate polymers; and ter-polymers of
dialkylfumarates, vinyl esters of fatty acids and alkyl vinyl ethers. Pour
point
depressants are described in U.S. Patent Nos. 2,387,501; 2,015,748; 2,655,479;
1,815,022; 2,191,498; 2,666,146; 2,721,877; 2,721,878; and 3,250,715, which
are
herein incorporated by reference for their relevant disclosures.
DISPERSANTS
[0056] Dispersants used in the present invention may be ash-producing or
ashless.
Suitable dispersants for use herein can typically comprise amine, alcohol,
amide, or
ester polar moieties attached to the polymer backbone via a bridging group.
The
dispersant may be, for example, selected from oil-soluble salts, esters, amino-
esters,
amides, imides, and oxazolines of long chain hydrocarbon substituted mono- and
dicarboxylic acids or their anhydrides; thiocarboxylate derivatives of chain
hydrocarbons; long chain aliphatic hydrocarbons having a polyamine attached
directly thereto; and Mannich condensation products formed by condensing a
long
chain substituted phenol with formaldehyde and polyalkylene polyamine, and
Koch
reaction products. The long chain aliphatic hydrocarbons can be polymers such
as
polyalkylenes, including, for example, polyisobutytene, polyethylene,
polypropylene,
and copolymers thereof and/or copolymers with other alpha-olefins. Typical PIS
molecular weights useful herein can range from about 950 to 6000.
14
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[0057] Representative examples of dispersants suitable for use in the present
invention are found in U.S. Patent Nos. 5,075,383; 5,139,688; 5,238,588; and
6,107,257. Additional representative examples are found in U.S. Patent
Application
Publication No. 2001l0036906A1. The disclosures of the afore~-mentioned
references are incorporated herein by reference.
DETERGENTS
(0058] A detergent is an additive that reduces the formation of piston
deposits, for
example high-temperature varnish and lacquer deposits, in engines. Detergents
typically possess acid-neutralizing properties and are capable of keeping
finely
divided solids in suspension. Metal detergents are used preferably for
improving the
acid-neutralizing properties, high-temperature detergency, and anti-wear
properties
of the resulting lubricating oil composition.
[0059] Detergents used herein may be any detergent used in lubricating oil
formulations, and may be of the ash-producing or ashless variety_ Detergents
suitable for use in the present invention include all of the detergents
customarily
used in lubricating oils, including metal detergents. Specific examples of
metal
detergents are those selected from alkali metal or alkaline earth metal
sulfonates,
alkali metal or alkaline earth metal phenates, and alkali metal or alkaline
earth metal
salicylates. In an embodiment, the lubricating oil formulation is essentially
free of
sulfurized phenate detergent.
[0060] Representative examples of suitable detergents useful in the present
invention are found in U.S. Pat. Nos. 6,008,166. Additional representative
examples
of suitable detergents are found in U.S. Patent Application Nos.
200210142922A1,
2002/0004069A1, and 200210147115A1. The disclosures of the afore-mentioned
references are incorporated by reference herein.
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ALKYLAMINE SALT OF A DIALKYLMONOTHIOPHOSPHATE
[4061]Although any oil soluble alkyiamine salt of a dialkylmonothiophosphate
that
imparts suitable anti-wear performance to the finished oil may be used in the
present
invention, a synthesis method for a preferred alkylamine salt of a
dialkylmonothiophosphate for use in the present invention follows.
[0062] In a round bottom flask equipped with a thermocouple, stirrer, addition
funnel
and condenser is charged 148.50 grams of ARMEEN OI . An effective amount of di-
n-butyl hydrogen phosphate (DBHP) is charged to the addition funnel. Begin
vigorous stirring of the ARMEEN OL and charge an effective amount of elemental
sulfur to the reactor. After the sulfur addition is complete, immediately
begin adding
the DBHP dropwise to the reactor. The reaction temperature should not exceed
70
°C. The temperature can be adjusted by the rate of DBHP addition. The
DBHP is
charged over four hours. The reaction should be monitored for DBHP buildup by
taking an IR each hour and checking the IR for unreacted DBHP. After the DBHP
addition is complete, charge the n-octylamine (13.29 grams). Heat the reaction
for
30 minutes at 50 °C.
[0063]ARMEEN OL is a commercial product from AKZO Nobel. ARMEEN OL is a
primary oleyl amine. Other amines supplied by AKZO Nobel suitable for this
invention include ARMEEN 12D, ARMEEN 16D, ARMEEN 18D, ARMEEN O,
ARMEEN OD, ARMEEN OLD, ARMEEN C, ARMEEN S, and ARMEEN SD. Any
primary, secondary or tertiary amine is suitable as long as the final product
is oil
soluble and it imparts suitable anti-wear performance to an oil.
[0064]The alykl groups on the phosphate andlor phosphate can be of any length
as
long as the final product is oil soluble and it imparts suitable anti-wear
performance
to an oil.
16
CA 02472803 2004-06-30
EI'-7604
ANTIOXIDANTS
[0065] Usefu! antioxidant materials include oil soluble phenolic compounds,
oil
soluble sulfurized organic compounds, oil soluble amine antioxidants, oil
soluble
organo borates, oil soluble organo phosphites, oil soluble organo phosphates,
oil
soluble organo dithiophosphates and mixtures thereof. Such antioxidants can be
metal free (that is, free of metals which are capable of generating sulfated
ash), and
therefore are most preferably ashless (having a sulfated ash value not greater
than 1
wt. % SASH, as determined by ASTM D874).
[0066) Representative examples of suitable antioxidants useful in the present
invention are found in U.S. Patent No. 5,102,566. Additoonal representative
examples of suitable antioxidants useful in the present invention are found in
U.S.
Patent Application Publication No. 200110012821A1. The disclosures of the
afore-
mentioned references are incorporated by reference herein.
FRICTION MODIFIERS
[0067) Friction modifiers serve to impart the proper friction characteristics
to
lubricating oil compositions.
[0068] Friction modifiers include such compounds as aliphatic amines or
ethoxylated
aliphatic amines, aliphatic fatty acid amines, aliphatic carboxylic acids,
aliphatic
carboxylic esters of polyols such as glycerol esters of fatty acid as
exemplified by
glycerol phenate, aliphatic carboxylic ester-amides, aliphatic phosphonates,
aliphatic
phosphates, aliphatic thiophosphonates, aliphatic thiophosphates, etc.,
wherein the
aliphatic group usually contains above about eight carban atoms so as to
render the
compound suitably oil soluble. Also suitable are aliphatic substituted
succinimides
formed by reacting one or more aliphatic succinic acids or anhydrides with
ammonia.
17
CA 02472803 2004-06-30
r P-7604
Additionally suited for use in the present invention are friction modifiers
containing
molybdenum.
(0069] Representative examples of molybdenum-containing friction modifiers
include
those found in U.S. Patent Nos. 5,650,381; RE37,363E; 5,628,802; 4,889,647;
5,412,130; 4,786,423; 4,812,246; 5,137,647; 5,364,545; 5,840,672; 5,925,600;
5,962,377; 5,994,277; 6,017,858; 6,150,309; 6,174,842; 6,187,723; 6,268,316;
European Patent Nos. EP 222 143 B1; EP 281 992 B1; EP 719 314 B1; EP 719 315
B1; EP 874 040 A1; EP 892 037 A1; EP 931 827 A1; EP 1 041 134 A1; EP 1 041
135 A1; EP 1 087 008 A1; EP 1 088 882 A1; EP; Japanese Patent No. JP
11035961; and International Publication Nos. WO 95/07965; WO 00/08120; WO
00171649.
[0070] Representative examples of suitable friction modifiers are found in
U.S. Pat.
Nos. 3,933,659; 4,105,571; 3,779,928; 3,778,375; 3,852,205; 3,879,306;
3,932,290;
3,932,290; 4,028,258; 4,344,853; 5,102,566; 6,103,674; 6,174,842; 6,500,786;
6,500,786; and 6,509,303. Additional representative examples of suitable
friction
modifiers are found in U.S. Patent Application Publication No. 200210137636
A1.
The disclosures of the above references are incorporated herein by reference.
CAT 7N ENGINE TEST RESULTS
[0071~The CAT 1N engine test is a commonly used test for evaluating the
acceptability of heavy-duty diesel engine oils for Caterpillar engines. The
test
employs a single cylinder aluminum piston diesel engine. The acceptability of
an oil
formulation is based upon the following parameters: average oil consumption,
piston
deposits, % top groove fill, % top land heavy carbon. Further, in order to
pass the
CAT 1 N diesel test, no stuck pistons, piston rings or liner distress is
permitted.
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CA 02472803 2004-06-30
EP-7604
[0072]To determine the efficacy of the inventive additive, a control
formulation
comprising a zinc dialkyldithiophosphate was compared to a formulation wherein
the
zinc dialkyldithiophosphate was replaced by an alkylamir~e salt of a
dialkylmonothiophosphate with a compensating reduction in the amount of base
oil.
Detergent #1 is a metal sulfonate and detergent #2 is a commercially available
metal
salicylate detergent. In this example, the weight ratio of alkylamine salt of
a
dialkylmonothiophosphate to combined detergents is 0.675 to 1.45 or about
1:2.14.
Composition, wt% basis Control FormulationInventive Formulation
Base Oil #1 52.00 51.575
Base Oil #2 27.00 27.00
Viscosit index Im rover 8.50 8.50
Pour Point De ressant 0.20 0.20
Dis ersant #1 3.00 3.00
Dis ersant #2 5.03 5.03
Deter ent #1 0.50 0.50
Deter ent #2 0.95 0.95
Alkylamine salt of a 0.00 0.675
dialk Imonothio hos hate
Zinc Dialk Idithio hos 0.25 0.00
hate
Antioxidant #1 0.50 0.50
Antioxidant #2 0.50 0.50
Anti-Foamin A ent 0.01 0.01
Friction Modifier 0.50 0.50
Process Oil 1.06 1.06
Kinematic Viscosit 100C 13.79 centistoke 13.17 centistoke
(0073]The following table compares the control formulatian's performance
against
the inventive formulation. The column marked "Test #1" provides the pass/fail
limits
for the CAT 1 N test for a single trial. if a given oil formul<~tion does not
provide
satisfactory results with a single trial, multiple trials may be averaged
together and
this average compared against the corresponding passJfail limits for the
number of
tests being averaged. That is to say, if two trials of the inventive
formulation were
19
CA 02472803 2004-06-30
EP-7604
averaged together, the averaged results would be compared against the
passlfaii
limits provided in the "Test#2" column.
Control Inventive Test Test #2 Test #3
FormulationFormulation#1
TLHC, % 0 0 3 4 5
TGF, % 9 9 20 23 25
WD 260.9 235.2 28fi.2311.7
O.C., av 0.205 0.201 323
0.5
max
0
-
252
hour
O.C.E.O.TØ21 0.212 No
scuffin
TLHC, % - Top Land Heavy Carbon
TGF, % - Top Groove Fill
WD - Weight of Deposit
O.C. - Oil Consumption
O.C.E.O.T. - Oil Consumption at End of Test
[0074]As can be seen from the table above, the inventive formulation performed
well
in the CAT 1 N test. The inventive formulation did not require additional
trials, as
single trial performance was satisfactory. The inventive formulation exhibited
a
marked reduction in weight of deposit. These results demonstrate the improved
performance imparted to the formulated oil by the substitution of an
aikylamine salt
of a dialkylmonothiophosphate for zinc dialkyldithiophosphate.
[0075] While the invention has been described in connection with what is
presently
considered to be the most practical and preferred embodiments, it is to be
understood that the invention is not to be limited to the disclosed
embodiment(s), but
on the contrary, is intended to cover various modifications and equivalent
arrangements included within the spirit and scope of the appended claims,
which are
incorporated herein by reference.
. . .. .. _ ... . _ ,.. ~n....~.~~.~~ ..,...~.w. ~ ~ . , ~.. ., _ ____.
