U.S. patent application number 16/288263 was filed with the patent office on 2019-08-29 for functional fluids lubricating oil compositions.
The applicant listed for this patent is Chevron Oronite Company LLC. Invention is credited to Juan A. Buitrago, Kevin J. Chase, Joshua B. James.
Application Number | 20190264128 16/288263 |
Document ID | / |
Family ID | 65991855 |
Filed Date | 2019-08-29 |
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United States Patent
Application |
20190264128 |
Kind Code |
A1 |
Buitrago; Juan A. ; et
al. |
August 29, 2019 |
FUNCTIONAL FLUIDS LUBRICATING OIL COMPOSITIONS
Abstract
Provided is a lubricating oil composition comprising a major
amount of an oil of lubricating viscosity and a detergent system,
and a method of improving brake and clutch capacity while
maintaining low torque variation at low speed of a tractor
hydraulic system.
Inventors: |
Buitrago; Juan A.;
(Hercules, CA) ; Chase; Kevin J.; (Martinez,
CA) ; James; Joshua B.; (Richmond, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chevron Oronite Company LLC |
San Ramon |
CA |
US |
|
|
Family ID: |
65991855 |
Appl. No.: |
16/288263 |
Filed: |
February 28, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62636305 |
Feb 28, 2018 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 169/048 20130101;
C10M 2219/044 20130101; C10M 2217/046 20130101; C10N 2040/252
20200501; C10N 2030/04 20130101; C10M 2219/046 20130101; C10M
2219/089 20130101; C10M 2205/022 20130101; C10M 159/24 20130101;
C10N 2010/04 20130101; C10N 2040/08 20130101; C10N 2040/04
20130101; C10M 169/042 20130101; C10N 2030/06 20130101; C10M
2207/028 20130101; C10M 159/22 20130101; C10M 2223/042 20130101;
C10M 2209/084 20130101; C10M 2219/044 20130101; C10N 2010/04
20130101; C10M 2219/046 20130101; C10N 2010/04 20130101; C10M
2207/028 20130101; C10N 2010/04 20130101; C10M 2207/028 20130101;
C10N 2020/071 20200501; C10M 2223/042 20130101; C10N 2010/04
20130101; C10M 2207/028 20130101; C10N 2020/071 20200501; C10M
2219/044 20130101; C10N 2010/04 20130101; C10M 2219/046 20130101;
C10N 2010/04 20130101; C10M 2207/028 20130101; C10N 2010/04
20130101; C10M 2223/042 20130101; C10N 2010/04 20130101 |
International
Class: |
C10M 159/22 20060101
C10M159/22 |
Claims
1. A tractor hydraulic fluid composition comprising: (a) a major
amount of an oil of lubricating viscosity, and (b) a detergent
system comprising: (i) a low overbased sulfonate detergent; (ii) a
high overbased sulfonate detergent; and (iii) a high overbased
phenate detergent having an alkyl group derived from an isomerized
normal alpha olefin having from about 10 to about 40 carbon atoms
per molecule.
2. The lubricating oil composition of claim 1 wherein the high
overbased phenate detergent is a calcium phenate detergent.
3. The lubricating oil composition of claim 2 wherein the calcium
phenate detergent is derived from C20 to C24 isomerized
olefins.
4. The lubricating oil composition of claim 1 wherein the
composition comprises from 0.005 to 0.08 wt. % Ca from the high
overbased phenate detergent.
5. The lubricating oil composition of claim 1 wherein the
composition comprises from 0.01 to 0.06 wt. % Ca from the high
overbased phenate detergent.
6. The lubricating oil composition of claim 1 wherein the
composition comprises a zinc diakyl dithioposphate detergent.
7. A method of improving brake and clutch capacity while
maintaining low torque variation at low speed of a tractor
hydraulic system, the method comprising lubricating said tractor
hydraulic system with a lubricating oil composition comprising: (a)
a major amount of an oil of lubricating viscosity, and (b) a
detergent system comprising: (i) a low overbased sulfonate
detergent; (ii) a high overbased sulfonate detergent; and (iii) a
high overbased phenate detergent having an alkyl group derived from
an isomerized normal alpha olefin having from about 10 to about 40
carbon atoms per molecule.
8. The method of claim 7, wherein the high overbased phenate
detergent is a calcium phenate detergent.
9. The method of claim 8, wherein the calcium phenate detergent is
derived from C20 to C24 isomerized olefins.
10. The method of claim 7, wherein the composition comprises from
0.005 to 0.08 wt. % Ca from the high overbased phenate
detergent.
11. The method of claim 10, wherein the composition comprises from
0.01 to 0.06 wt. % Ca from the high overbased phenate
detergent.
12. The method of claim 7, wherein the composition comprises a zinc
diakyl dithioposphate detergent.
Description
BACKGROUND OF THE DISCLOSURE
[0001] Modern lubricating oil formulations are designed to exacting
specifications often set by original equipment manufacturers. To
meet such specifications, various additives are used, together with
base oils of lubricating viscosity. Depending on the application, a
typical lubricating oil composition may contain dispersants,
detergents, anti-oxidants, wear inhibitors, rust inhibitors,
corrosion inhibitors, foam inhibitors, and friction modifiers just
to name a few. Different applications will govern the type of
additives that will go into a lubricating oil composition.
[0002] A functional fluid is a term which encompasses a variety of
fluids including but not limited to tractor hydraulic fluids, power
transmission fluids including automatic transmission fluids,
continuously variable transmission fluids and manual transmission
fluids, hydraulic fluids, gear oils, power steering fluids, fluids
used in wind turbines and fluids related to power train components.
It should be noted that within each of these fluids such as, for
example, automatic transmission fluids, there are a variety of
different types of fluids due to the various transmissions having
different designs which have led to the need for fluids of markedly
different functional characteristics.
[0003] With respect to tractor hydraulic fluids, these fluids are
all-purpose (or multi-purpose) products used for all lubricant
applications in a tractor except for lubricating the engine. Also
included as a tractor hydraulic fluid for the purposes of this
invention are so-called Super Tractor Oil Universal fluids or
"STOU" fluids, which also lubricate the engine. These lubricating
applications may include lubrication of gearboxes, power take-off
and clutch(es), rear axles, reduction gears, wet brakes, and
hydraulic accessories. The components included within a tractor
fluid must be carefully chosen so that the final resulting fluid
composition will provide all the necessary characteristics required
in the different applications. Such characteristics may include the
ability to provide proper frictional properties for preventing wet
brake and/or clutch chatter of oil immersed brakes and clutches
while simultaneously providing the ability to actuate wet brakes
and clutches, particularly provide power take-off (PTO) clutch
performance. A tractor fluid must provide sufficient antiwear and
extreme pressure properties as well as water
tolerance/filterability capabilities. The extreme pressure (EP)
properties of tractor fluids, important in gearing applications,
may be demonstrated by the ability of the fluid to pass a spiral
bevel test as well as a straight spur gear test. The tractor fluid
may need to pass wet brake chatter tests while providing adequate
wet brake capacity when used in oil immersed disk brakes which are
comprised of cellulose, bronze, graphitic-compositions and
asbestos, among other materials. The tractor fluid may need to
demonstrate its ability to provide friction retention for power
shift transmission clutches such as those clutches which include,
cellulose and graphitic clutches, among other materials.
[0004] When the functional fluid is a tractor hydraulic fluid, the
fluids must have enough friction for the system to operate
effectively. The term "friction durability" will be used to
describe the property of the fluid to retain its original
frictional properties. For example, a fluid with good friction
durability will exhibit small changes in the frictional properties
during its useful life. It is important that the tractor hydraulic
fluid maintains its frictional properties throughout its life to
ensure optimal operation of brakes and clutches.
[0005] The present disclosure generally relates to lubricating oil
compositions which improve or maintain frictional durability while
maintaining low torque variation at low speed when used as tractor
hydraulic fluids.
SUMMARY OF THE DISCLOSURE
[0006] In accordance with one embodiment of the present disclosure,
there is provided a tractor hydraulic fluid composition which
comprises:
[0007] (a) a major amount of an oil of lubricating viscosity,
and
[0008] (b) a detergent system comprising: [0009] (i) a low
overbased sulfonate detergent; [0010] (ii) a high overbased
sulfonate detergent; and [0011] (iii) a high overbased phenate
detergent having an alkyl group derived from an isomerized normal
alpha olefin having from about 10 to about 40 carbon atoms per
molecule.
[0012] Also provided is a method of improving frictional durability
while maintaining low torque variation at low speed of a tractor
hydraulic system comprising lubricating said hydraulic system with
a lubricating oil composition comprising:
[0013] (a) a major amount of an oil of lubricating viscosity,
and
[0014] (b) a detergent system comprising: [0015] (i) a low
overbased sulfonate detergent; [0016] (ii) a high overbased
sulfonate detergent; and [0017] (iii) a high overbased phenate
detergent having an alkyl group derived from an isomerized normal
alpha olefin having from about 10 to about 40 carbon atoms per
molecule.
DETAILED DESCRIPTION OF THE DISCLOSURE
[0018] While the invention is susceptible to various modifications
and alternative forms, specific embodiments thereof are herein
described in detail. It should be understood, however, that the
description herein of specific embodiments is not intended to limit
the invention to the particular forms disclosed, but on the
contrary, the intention is to cover all modifications, equivalents,
and alternatives falling within the spirit and scope of the
invention as defined by the appended claims.
[0019] To facilitate the understanding of the subject matter
disclosed herein, a number of terms, abbreviations or other
shorthand as used herein are defined below. Any term, abbreviation
or shorthand not defined is understood to have the ordinary meaning
used by a skilled artisan contemporaneous with the submission of
this application.
Definitions
[0020] As used herein, the following terms have the following
meanings, unless expressly stated to the contrary. In this
specification, the following words and expressions, if and when
used, have the meanings given below.
[0021] A "major amount" means in excess of 50 weight % of a
composition.
[0022] A "minor amount" means less than 50 weight % of a
composition, expressed in respect of the stated additive and in
respect of the total mass of all the additives present in the
composition, reckoned as active ingredient of the additive or
additives.
[0023] "Active ingredients" or "actives" or "oil free" refers to
additive material that is not diluent or solvent.
[0024] The abbreviation "ppm" means parts per million by weight,
based on the total weight of the lubricating oil composition.
[0025] Total base number (TBN) was determined in accordance with
ASTM D2896. TBN numbers are reported on an "actives" or "oil-free"
basis.
[0026] Metal--The term "metal" refers to alkali metals, alkaline
earth metals, or mixtures thereof.
[0027] Kinematic viscosity at 100.degree. C. (KV.sub.100) was
determined in accordance with ASTM D445.
[0028] Olefins--The term "olefins" refers to a class of unsaturated
aliphatic hydrocarbons having one or more carbon-carbon double
bonds, obtained by a number of processes. Those containing one
double bond are called mono-alkenes, and those with two double
bonds are called dienes, alkyldienes, or diolefins. Alpha olefins
are particularly reactive because the double bond is between the
first and second carbons. Examples are 1-octene and 1-octadecene,
which are used as the starting point for medium-biodegradable
surfactants. Linear and branched olefins are also included in the
definition of olefins.
[0029] Normal Alpha Olefins--The term "Normal Alpha Olefins" refers
to olefins which are straight chain, non-branched hydrocarbons with
carbon-carbon double bond present in beginning and end of the
chain.
[0030] Isomerized Normal Alpha Olefin. The term "Isomerized Normal
Alpha Olefin" as used herein refers to an alpha olefin that has
been subjected to isomerization conditions which results in an
alteration of the distribution of the olefin species present and/or
the introduction of branching along the alkyl chain. The isomerized
olefin product may be obtained by isomerizing a linear alpha olefin
containing from about 10 to about 40 carbon atoms, preferably from
about 20 to about 28 carbon atoms, and preferably from about 20 to
about 24 carbon atoms.
[0031] All ASTM standards referred to herein are the most current
versions as of the filing date of the present application.
[0032] In one aspect, the lubricating oil composition of the
present disclosure improves frictional durability while maintaining
low torque variation at low speed when used as a tractor hydraulic
fluid. In another aspect, the lubricating oil composition of the
present disclosure maintains frictional durability while
maintaining low torque variation at low speed when used as a
tractor hydraulic fluid.
[0033] In one aspect, the lubricating oil composition of the
present disclosure comprises a detergent system comprising: a low
overbased sulfonate detergent, a high overbased sulfonate
detergent; and a high overbased phenate detergent.
[0034] In another aspect, the detergent system of the present
disclosure provides synergistic performance benefits when used in
lubricating oil compositions for tractor hydraulic fluids.
Oil of Lubricating Viscosity
[0035] The oil of lubricating viscosity (sometimes referred to as
"base stock" or "base oil") is the primary liquid constituent of a
lubricant, into which additives and possibly other oils are
blended, for example to produce a final lubricant (or lubricant
composition). A base oil is useful for making concentrates as well
as for making lubricating oil compositions therefrom, and may be
selected from natural and synthetic lubricating oils and
combinations thereof.
[0036] Natural oils include animal and vegetable oils, liquid
petroleum oils and hydrorefined, solvent-treated mineral
lubricating oils of the paraffinic, naphthenic and mixed
paraffinic-naphthenic types. Oils of lubricating viscosity derived
from coal or shale are also useful base oils.
[0037] Synthetic lubricating oils include hydrocarbon oils such as
polymerized and interpolymerized olefins (e.g., polybutylenes,
polypropylenes, propylene-isobutylene copolymers, chlorinated
polybutylenes, poly(l-hexenes), poly(1-octenes), poly(1-decenes);
alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes,
dinonylbenzenes, di(2-ethylhexyl)benzenes; polyphenols (e.g.,
biphenyls, terphenyls, alkylated polyphenols); and alkylated
diphenyl ethers and alkylated diphenyl sulfides and the
derivatives, analogues and homologues thereof.
[0038] Another suitable class of synthetic lubricating oils
comprises the esters of dicarboxylic acids (e.g., malonic acid,
alkyl malonic acids, alkenyl malonic acids, succinic acid, alkyl
succinic acids and alkenyl succinic acids, maleic acid, fumaric
acid, azelaic acid, suberic acid, sebacic acid, adipic acid,
linoleic acid dimer, phthalic acid) with a variety of alcohols
(e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl
alcohol, ethylene glycol, diethylene glycol monoether, propylene
glycol). Specific examples of these esters include dibutyl adipate,
di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate,
diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl
phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic
acid dimer, and the complex ester formed by reacting one mole of
sebacic acid with two moles of tetraethylene glycol and two moles
of 2-ethylhexanoic acid.
[0039] Esters useful as synthetic oils also include those made from
C5 to C12 monocarboxylic acids and polyols, and polyol ethers such
as neopentyl glycol, trimethylolpropane, pentaerythritol,
dipentaerythritol and tripentaerythritol.
[0040] The base oil may be derived from Fischer-Tropsch synthesized
hydrocarbons.
[0041] Fischer-Tropsch synthesized hydrocarbons are made from
synthesis gas containing H2 and CO using a Fischer-Tropsch
catalyst. Such hydrocarbons typically require further processing in
order to be useful as the base oil. For example, the hydrocarbons
may be hydroisomerized; hydrocracked and hydroisomerized; dewaxed;
or hydroisomerized and dewaxed; using processes known to those
skilled in the art.
[0042] Unrefined, refined and re-refined oils can be used in the
present lubricating oil composition. Unrefined oils are those
obtained directly from a natural or synthetic source without
further purification treatment. For example, a shale oil obtained
directly from retorting operations, a petroleum oil obtained
directly from distillation or ester oil obtained directly from an
esterification process and used without further treatment would be
unrefined oil. 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. Many such purification
techniques, such as distillation, solvent extraction, acid or base
extraction, filtration and percolation are known to those skilled
in the art.
[0043] Re-refined oils are obtained by processes similar to those
used to obtain refined oils applied to refined oils which have been
already used in service. Such re-refined oils are also known as
reclaimed or reprocessed oils and often are additionally processed
by techniques for approval of spent additive and oil breakdown
products.
[0044] Hence, the base oil which may be used to make the present
lubricating oil composition may be selected from any of the base
oils in Groups I-V as specified in the American Petroleum Institute
(API) Base Oil Interchangeability Guidelines (API Publication
1509). Such base oil groups are summarized in Table 1 below:
TABLE-US-00001 TABLE 1 Base Oil Properties Group.sup.(a)
Saturates.sup.(b), wt. % Sulfur.sup.(c), wt. % Viscosity
Index.sup.(d) Group I <90 and/or >0.03 80 to <120 Group II
.gtoreq.90 .ltoreq.0.03 80 to <120 Group III .gtoreq.90
.ltoreq.0.03 .gtoreq.120 Group IV Polyalphaolefins (PAOs) Group V
All other base stocks not included in Groups I, II, III or IV
.sup.(a)Groups I-III are mineral oil base stocks.
.sup.(b)Determined in accordance with ASTM D2007.
.sup.(c)Determined in accordance with ASTM D2622, ASTM D3120, ASTM
D4294 or ASTM D4927. .sup.(d)Determined in accordance with ASTM
D2270.
[0045] Base oils suitable for use herein are any of the variety
corresponding to API Group II, Group III, Group IV, and Group V
oils and combinations thereof, preferably the Group III to Group V
oils due to their exceptional volatility, stability, viscometric
and cleanliness features.
[0046] The oil of lubricating viscosity for use in the lubricating
oil compositions of this disclosure, also referred to as a base
oil, is typically present in a major amount, e.g., an amount of
greater than 50 wt. %, preferably greater than about 70 wt. %, more
preferably from about 80 to about 99.5 wt. % and most preferably
from about 85 to about 98 wt. %, based on the total weight of the
composition. The expression "base oil" as used herein shall be
understood to mean a base stock or blend of base stocks which is a
lubricant component that is produced by a single manufacturer to
the same specifications (independent of feed source or
manufacturer's location); that meets the same manufacturer's
specification; and that is identified by a unique formula, product
identification number, or both. The base oil for use herein can be
any presently known or later-discovered oil of lubricating
viscosity used in formulating lubricating oil compositions for any
and all such applications, e.g., engine oils, marine cylinder oils,
functional fluids such as hydraulic oils, gear oils, transmission
fluids, etc. Additionally, the base oils for use herein can
optionally contain viscosity index improvers, e.g., polymeric
alkylmethacrylates; olefinic copolymers, e.g., an
ethylene-propylene copolymer or a styrene-butadiene copolymer; and
the like and mixtures thereof.
[0047] As one skilled in the art would readily appreciate, the
viscosity of the base oil is dependent upon the application.
Accordingly, the viscosity of a base oil for use herein will
ordinarily range from about 2 to about 2000 centistokes (cSt) at
100.degree. Centigrade (C.). Generally, individually the base oils
used as engine oils will have a kinematic viscosity range at
100.degree. C. of about 2 cSt to about 30 cSt, preferably about 3
cSt to about 16 cSt, and most preferably about 4 cSt to about 12
cSt and will be selected or blended depending on the desired end
use and the additives in the finished oil to give the desired grade
of engine oil, e.g., a lubricating oil composition having an SAE
Viscosity Grade of 0W, 0W-8, 0W-12, 0W-16, 0W-20, 0W-26, 0W-30,
0W-40, 0W-50, 0W-60, 5W, 5W-20, 5W-30, 5W-40, 5W-50, 5W-60, 10W,
10W-20, 10W-30, 10W-40, 10W-50, 15W, 15W-20, 15W-30, 15W-40, 20,
30, 40, 50 and the like. Also, oils could be blended in viscosity
grades specific to tractor hydraulic fluids such as J20C and/or
J20D.
Low Overbased (LOB) Sulfonate Detergent
[0048] The compositions described herein comprise low overbased
alkaryl sulfonate salts. In particular, the compositions comprise:
[0049] (i) at least one low overbased alkaryl sulfonate calcium
salt wherein the alkaryl group is an aryl group substituted with an
alkyl group derived from propylene or isobutylene oligomers; and/or
[0050] (ii) at least one low overbased alkaryl sulfonate calcium
salt, wherein the alkaryl group is an aryl group substituted with
an alkyl group derived from at least one normal alpha olefin or an
isomerized normal alpha olefin, said olefin having from about 18 to
about 30 carbon atoms.
[0051] These low overbased alkaryl sulfonate calcium salts can
serve, e.g., as detergents and friction providers in the
compositions described herein.
[0052] In some embodiments, the low overbased alkaryl sulfonate
detergent is derived from an alkali metal, an alkaline earth metal,
or mixtures thereof.
[0053] In some embodiments, the at least one low overbased alkaryl
sulfonate calcium salt having an alkaryl group that is an aryl
group substituted with an alkyl group derived from propylene or
isobutylene oligomers has the following formula A:
##STR00001##
[0054] wherein R is an alkyl group derived from propylene or
isobutylene oligomers;
R.sup.X is hydrogen or methyl, m is 0 to 5; and n is 1 or greater.
In some embodiments, m is 0.1-5. In some embodiments, n is 1. In
some embodiments, the alkyl group has 3-36, 9-27, or 15-18 carbons.
In some embodiments, the alkyl group is derived from propylene
oligomers.
[0055] In some embodiments, the at least one low overbased alkaryl
sulfonate calcium salt having an alkaryl group that is an aryl
group substituted with an alkyl group derived from at least one
normal alpha olefin or an isomerized normal alpha olefin, said
olefin having from about 18 to about 30 carbon atoms, has the
following structure B:
##STR00002##
wherein R is an alkyl group derived from at least one normal alpha
olefin or an isomerized normal alpha olefin, said olefin having
from about 18 to about 30 carbon atoms; R.sup.X is hydrogen or
methyl, m is 0 to 5; and n is 1 or greater. In some embodiments, m
is 0.1-5. In some embodiments, n is 1.
[0056] In some embodiments, each of the low overbased alkaryl
sulfonate calcium salts (A) or (B) above is a low overbased
alkyl-substituted benzene or low overbased alkyl-substituted
toluene sulfonate calcium salt.
[0057] The calcium content accounted for by the at least one low
overbased alkaryl sulfonate calcium salt (A) or (B) present in the
oil composition is 0.001 to 0.1 weight percent of the lubricating
oil composition. In some embodiments, the calcium content is 0.01
to 0.09, 0.01 to 0.08, 0.01 to 0.07, or 0.01 to 0.06, 0.01 to 0.05,
0.01 to 0.04, 0.01 to 0.03, 0.01 to 0.02 weight percent of the
lubricating oil.
[0058] In some embodiments, the low overbased alkaryl sulfonate
calcium salt (B) is one wherein the alkaryl group is an aryl group
substituted with an alkyl group derived from at least one normal
alpha olefin or an isomerized normal alpha olefin, said olefin
having from about 20 to about 24 carbon atoms.
[0059] In some embodiments, each or both of the alkaryl sulfonate
calcium salts (A) or (B) is low overbased, wherein the TBN is less
than 150, less than 140, less than 130, less than 120, less than
110, less than 100, less than 90, less than 80, less than 70, less
than 60, less than 50, less than 40, less than 30, less than 20, or
less than 10. In some embodiments, each or both of the alkyaryl
sulfonate calcium salts (A) or (B) has a TBN of 2-100, 2-80, or
2-60.
High Overbased (HOB) Sulfonate Detergent
[0060] The lubricating oil composition of the present invention can
contain one or more high overbased sulfonate detergents having a
TBN of 300-800, 400-800, 400-700, 450-700, 500-700, 500-700,
500-600 mg KOH/g on an actives basis.
[0061] Sulfonates may be prepared from sulfonic acids which are
typically obtained by the sulfonation of alkyl substituted aromatic
hydrocarbons such as those obtained from the fractionation of
petroleum or by the alkylation of aromatic hydrocarbons. Examples
included those obtained by alkylating benzene, toluene, xylene,
naphthalene, diphenyl or their halogen derivatives. The alkylation
may be carried out in the presence of a catalyst with alkylating
agents having from about 3 to more than 70 carbon atoms. The
alkaryl sulfonates usually contain from about 9 to about 80 or more
carbon atoms, preferably from about 16 to about 60 carbon atoms,
preferably about 16 to 30 carbon atoms, and more preferably 20-24
carbon atoms per alkyl substituted aromatic moiety.
[0062] In some embodiments, the high overbased detergent is a high
overbased alkaryl sulfonate calcium detergent. In some embodiments,
the calcium content of the high overbased detergent is 0.001 to
2.0, 0.01 1.0, 0.01 to 0.90, 0.01 to 0.70, 0.01 to 0.50, 0.01 to
0.40, 0.01 to 0.30; 0.01 to 0.20, 0.01 to 0.17 weight percent of
the lubricating oil composition.
High Overbased (HOB) Phenate Detergent
[0063] In one aspect of the present disclosure, the high overbased
phenate detergent is a phenolic-based detergent. In another aspect
of the present disclosure, the phenolic-based detergent is an
isomerized olefin phenate detergent.
[0064] In one aspect of the present disclosure, the high overbased
phenate detergent has a TBN of 300-600, 300-500, 300-450, 300-400,
325-425, 350-425, 350-400 mgKOH/gram on an oil free basis.
[0065] In one aspect of the present disclosure, the phenolic-based
detergent is an alkylated phenate detergent wherein the alkyl group
is derived from an isomerized normal alpha olefin having from about
10 to about 40 carbon atoms per molecule.
[0066] In one aspect of the present disclosure, the phenolic-based
detergent has an isomerization level (I) of the normal alpha olefin
is between from about 0.10 to about 0.40, preferably from about
0.10 to about 0.30, preferably from about 0.12 to about 0.30, and
more preferably from about 0.22 to about 0.30.
[0067] In one aspect of the present disclosure, the phenate
detergent is a sulfurized phenate detergent.
[0068] In one aspect of the present disclosure, the isomerized
olefin phenate detergent can be prepared as described in U.S. Pat.
No. 8,580,717 which is herein incorporated in its entirety.
[0069] In one aspect of the present disclosure, the alkyl group is
derived from an isomerized alpha olefin having from about 14 to
about 30, from about 16 to about 30, from about 18 to about 30,
from about 20 to about 28, 20 to about 24, or from about 18 to
about 28 carbon atoms per molecule.
[0070] In another embodiment, the isomerization level of the
alphaolefin is about 0.26, and having from about 20 to about 24
carbon atoms.
[0071] In some embodiments, the calcium content of the high
overbased phenate detergent is from 0.005 to 0.08, 0.01 to 0.08,
0.01 to 0.07, 0.01 to 0.06, 0.01 to 0.05, 0.01 to 0.045 weight
percent, based on the weight of the oil composition.
Other Detergents
[0072] Other detergents that may be used include oil-soluble
overbased sulfonate, salixarate, salicylate, saligenin, complex
detergents and naphthenate detergents and other oil-soluble
alkylhydroxybenzoates of a metal, particularly the alkali or
alkaline earth metals, e.g., barium, sodium, potassium, lithium,
calcium, and magnesium. The most commonly used metals are calcium
and magnesium, which may both be present in detergents used in a
lubricant, and mixtures of calcium and/or magnesium with
sodium.
[0073] Overbased metal detergents are generally produced by
carbonating a mixture of hydrocarbons, detergent acid, for example:
sulfonic acid, alkylhydroxybenzoate etc., metal oxide or hydroxides
(for example calcium oxide or calcium hydroxide) and promoters such
as xylene, methanol and water. For example, for preparing an
overbased calcium sulfonate, in carbonation, the calcium oxide or
hydroxide reacts with the gaseous carbon dioxide to form calcium
carbonate. The sulfonic acid is neutralized with an excess of CaO
or Ca(OH).sub.2, to form the sulfonate.
[0074] Overbased detergents may be low overbased, e.g., an
overbased salt having a TBN below 100 on an actives basis. In one
embodiment, the TBN of a low overbased salt may be from about 30 to
about 100. In another embodiment, the TBN of a low overbased salt
may be from about 30 to about 80. Overbased detergents may be
medium overbased, e.g., an overbased salt having a TBN from about
100 to about 250. In one embodiment, the TBN of a medium overbased
salt may be from about 100 to about 200. In another embodiment, the
TBN of a medium overbased salt may be from about 125 to about 175.
Overbased detergents may be high overbased, e.g., an overbased salt
having a TBN above 250. In one embodiment, the TBN of a high
overbased salt may be from about 250 to about 800 on an actives
basis.
[0075] In one embodiment, the detergent can be one or more alkali
or alkaline earth metal salts of an alkyl-substituted
hydroxyaromatic carboxylic acid. Suitable hydroxyaromatic compounds
include mononuclear monohydroxy and polyhydroxy aromatic
hydrocarbons having 1 to 4, and preferably 1 to 3, hydroxyl groups.
Suitable hydroxyaromatic compounds include phenol, catechol,
resorcinol, hydroquinone, pyrogallol, cresol, and the like. The
preferred hydroxyaromatic compound is phenol.
[0076] The alkyl substituted moiety of the alkali or alkaline earth
metal salt of an alkyl-substituted hydroxyaromatic carboxylic acid
is derived from an alpha olefin having from about 10 to about 80
carbon atoms. The olefins employed may be linear, isomerized
linear, branched or partially branched linear. The olefin may be a
mixture of linear olefins, a mixture of isomerized linear olefins,
a mixture of branched olefins, a mixture of partially branched
linear or a mixture of any of the foregoing.
[0077] In one embodiment, the mixture of linear olefins that may be
used is a mixture of normal alpha olefins selected from olefins
having from about 10 to about 40 carbon atoms per molecule. In one
embodiment, the normal alpha olefins are isomerized using at least
one of a solid or liquid catalyst.
[0078] In one embodiment, at least about 50 mole %, at least about
75 mole %, at least about 80 mole %, at least about 85 mole %, at
least about 90 mole %, at least about 95 mole % of the alkyl groups
contained within the alkali or alkaline earth metal salt of an
alkyl-substituted hydroxyaromatic carboxylic acid such as the alkyl
groups of an alkaline earth metal salt of an alkyl-substituted
hydroxybenzoic acid detergent are a C.sub.20 or higher. In another
embodiment, the alkali or alkaline earth metal salt of an
alkyl-substituted hydroxyaromatic carboxylic acid is an alkali or
alkaline earth metal salt of an alkyl-substituted hydroxybenzoic
acid that is derived from an alkyl-substituted hydroxybenzoic acid
in which the alkyl groups are C.sub.20 to about C.sub.28 normal
alpha-olefins. In another embodiment, the alkyl group is derived
from at least two alkylated phenols. The alkyl group on at least
one of the at least two alkyl phenols is derived from an isomerized
alpha olefin. The alkyl group on the second alkyl phenol may be
derived from branched or partially branched olefins, highly
isomerized olefins or mixtures thereof.
[0079] In another embodiment, the alkali or alkaline earth metal
salt of an alkyl-substituted hydroxyaromatic carboxylic acid is a
salicylate derived from an alkyl group with 20-40 carbon atoms,
preferably 20-28 carbon atoms, more preferably, isomerized 20-24
NAO.
Antiwear Agents
[0080] The lubricating oil composition disclosed herein can
comprise one or more antiwear agent. Antiwear agents reduce wear of
metal parts. Suitable anti-wear agents include dihydrocarbyl
dithiophosphate metal salts such as zinc dihydrocarbyl
dithiophosphates (ZDDP) of formula (Formula 1):
Zn[S--P(.dbd.S)(OR.sup.1)(OR.sup.2)].sub.2 Formula 1,
[0081] wherein R.sup.1 and R.sup.2 may be the same of different
hydrocarbyl radicals having from 1 to 18 (e.g., 2 to 12) carbon
atoms and including radicals such as alkyl, alkenyl, aryl,
arylalkyl, alkaryl and cycloaliphatic radicals. Particularly
preferred as R.sup.1 and R.sup.2 groups are alkyl groups having
from 2 to 8 carbon atoms (e.g., the alkyl radicals may be ethyl,
n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl,
isopentyl, n-hexyl, isohexyl, 2-ethylhexyl). In order to obtain oil
solubility, the total number of carbon atoms (i.e.,
R.sup.1+R.sup.2) will be at least 5. The zinc dihydrocarbyl
dithiophosphate can therefore comprise zinc dialkyl
dithiophosphates. The zinc dialkyl dithiophosphate is a primary,
secondary zinc dialkyl dithiophosphate, or a combination thereof.
ZDDP may be present at 3 wt. % or less (e.g., 0.1 to 1.5 wt. %, or
0.5 to 1.0 wt %) of the lubricating oil composition.
Antioxidants
[0082] The lubricating oil composition disclosed herein can
comprise one or more antioxidant. Antioxidants reduce the tendency
of mineral oils during to deteriorate during service. Oxidative
deterioration can be evidenced by sludge in the lubricant,
varnish-like deposits on the metal surfaces, and by viscosity
growth. Suitable antioxidants include hindered phenols, aromatic
amines, hindered amines (also known as HALS-Hindered Amine light
Stabilizers) and sulfurized alkylphenols and alkali and alkaline
earth metals salts thereof.
[0083] The hindered amines used in this invention are of many
types, with three types predominating: pyrimidines, piperidines and
stable nitroxide compounds. Many more are described in the book
"Nitrones, Nitronates, and Nitroxides", E. Breuer, et al., 1989,
John Wiley & Sons and in Patents such as U.S. Pat. No.
9,315,760.
[0084] The hindered phenol antioxidant often contains a secondary
butyl and/or a tertiary butyl group as a sterically hindering
group. The phenol group may be further substituted with a
hydrocarbyl group (typically linear or branched alkyl) and/or a
bridging group linking to a second aromatic group. Examples of
suitable hindered phenol antioxidants include 2,6-di-ter
t-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; and
4-dodecyl-2,6-di-tert-butylphenol. Other useful hindered phenol
antioxidants include 2,6-di-alkyl-phenolic propionic ester
derivatives such as IRGANOX.RTM. L-135 from Ciba and bis-phenolic
antioxidants such as 4,4'-bis(2,6-di-tert-butylphenol) and
4,4'-methylenebis(2,6-di-tert-butylphenol). Typical aromatic amine
antioxidants have at least two aromatic groups attached directly to
one amine nitrogen. Typical aromatic amine antioxidants have alkyl
substituent groups of at least 6 carbon atoms. Particular examples
of aromatic amine antioxidants useful herein include
4,4'-dioctyldiphenylamine, 4,4'-dinonyldiphenylamine,
N-phenyl-1-naphthylamine, N-(4-tert-octyphenyl)-1-naphthylamine,
and N-(4-octylphenyl)-1-naphthylamine. Antioxidants may be present
at 0.01 to 5 wt. % (e.g., 0.1 to 2 wt. %) of the lubricating oil
composition.
Dispersants
[0085] The lubricating oil composition disclosed herein can
comprise one or more dispersant. Dispersants maintain in suspension
materials resulting from oxidation that are insoluble in oil, thus
preventing sludge flocculation and precipitation or deposition on
metal parts. Dispersants useful herein include nitrogen-containing,
ashless (metal-free) dispersants known to effective to reduce
formation of deposits upon use in gasoline and diesel engines.
[0086] Suitable dispersants include hydrocarbyl succinimides,
hydrocarbyl succinamides, mixed ester/amides of
hydrocarbyl-substituted succinic acid, hydroxyesters of
hydrocarbyl-substituted succinic acid, and Mannich condensation
products of hydrocarbyl-substituted phenols, formaldehyde and
polyamines. Also suitable are condensation products of polyamines
and hydrocarbyl-substituted phenyl acids. Mixtures of these
dispersants can also be used. Basic nitrogen-containing ashless
dispersants are well-known lubricating oil additives and methods
for their preparation are extensively described in the patent
literature. Preferred dispersants are the alkenyl succinimides and
succinamides where the alkenyl-substituent is a long-chain of
preferably greater than 40 carbon atoms. These materials are
readily made by reacting a hydrocarbyl-substituted dicarboxylic
acid material with a molecule containing amine functionality.
Examples of suitable amines are polyamines such as polyalkylene
polyamines, hydroxy-substituted polyamines and polyoxyalkylene
polyamines.
[0087] Particularly preferred ashless dispersants are the
polyisobutenyl succinimides formed from polyisobutenyl succinic
anhydride and a polyalkylene polyamine such as a polyethylene poly
amine of formula 2:
NH.sub.2(CH.sub.2CH.sub.2NH).sub.zH Formula 2,
wherein z is 1 to 11. The polyisobutenyl group is derived from
polyisobutene and preferably has a number average molecular weight
(M.sub.n) in a range of 700 to 3000 Daltons (e.g., 900 to 2500
Daltons). For example, the polyisobutenyl succinimide may be a
mono-succinimide or a bis-succinimide derived from a polyisobutenyl
group having a M.sub.n of 900 to 2500 Daltons. As is known in the
art, the dispersants may be post-treated (e.g., with a boronating
agent or a cyclic carbonate, ethylene carbonate etc).
[0088] Nitrogen-containing ashless (metal-free) dispersants are
basic, and contribute to the TBN of a lubricating oil composition
to which they are added, without introducing additional sulfated
ash. Dispersants may be present at 0.1 to 10 wt. % (e.g., 2 to 5
wt. %) of the lubricating oil composition.
Foam Inhibitors
[0089] The lubricating oil composition disclosed herein can
comprise one or more foam inhibitor that can break up foams in
oils. Non-limiting examples of suitable foam inhibitors or
anti-foam inhibitors include silicone oils or
polydimethylsiloxanes, fluorosilicones, alkoxylated aliphatic
acids, polyethers (e.g., polyethylene glycols), branched polyvinyl
ethers, alkyl acrylate polymers, alkyl methacrylate polymers,
polyalkoxyamines and combinations thereof.
Additional Co-Additives
[0090] The lubricating oil compositions of the present disclosure
may also contain other conventional additives that can impart or
improve any desirable property of the lubricating oil composition
in which these additives are dispersed or dissolved. Any additive
known to a person of ordinary skill in the art may be used in the
lubricating oil compositions disclosed herein. Some suitable
additives have been described in Mortier et al., "Chemistry and
Technology of Lubricants", 2nd Edition, London, Springer, (1996);
and Leslie R. Rudnick, "Lubricant Additives: Chemistry and
Applications", New York, Marcel Dekker (2003), both of which are
incorporated herein by reference. For example, the lubricating oil
compositions can be blended with antioxidants, anti-wear agents,
detergents such as metal detergents, rust inhibitors, dehazing
agents, demulsifying agents, metal deactivating agents, friction
modifiers, pour point depressants, antifoaming agents, co-solvents,
corrosion-inhibitors, ashless dispersants, multifunctional agents,
dyes, extreme pressure agents and the like and mixtures thereof. A
variety of the additives are known and commercially available.
These additives, or their analogous compounds, can be employed for
the preparation of the lubricating oil compositions of the
disclosure by the usual blending procedures.
[0091] In the preparation of lubricating oil formulations, it is
common practice to introduce the additives in the form of 10 to 100
wt. % active ingredient concentrates in hydrocarbon oil, e.g.
mineral lubricating oil, or other suitable solvent.
[0092] Usually these concentrates may be diluted with 3 to 100,
e.g., 5 to 40, parts by weight of lubricating oil per part by
weight of the additive package in forming finished lubricants, e.g.
tractor hydraulic fluids. The purpose of concentrates, of course,
is to make the handling of the various materials less difficult and
awkward as well as to facilitate solution or dispersion in the
final blend.
[0093] Each of the foregoing additives, when used, is used at a
functionally effective amount to impart the desired properties to
the lubricant. Thus, for example, if an additive is a friction
modifier, a functionally effective amount of this friction modifier
would be an amount sufficient to impart the desired friction
modifying characteristics to the lubricant.
[0094] In general, the concentration of each of the additives in
the lubricating oil composition, when used, may range from about
0.001 wt. % to about 20 wt. %, from about 0.01 wt. % to about 15
wt. %, or from about 0.1 wt. % to about 10 wt. %, from about 0.005
wt. % to about 5 wt. %, or from about 0.1 wt. % to about 2.5 wt. %,
based on the total weight of the lubricating oil composition.
Further, the total amount of the additives in the lubricating oil
composition may range from about 0.001 wt. % to about 20 wt. %,
from about 0.01 wt. % to about 10 wt. %, or from about 0.1 wt. % to
about 5 wt. %, based on the total weight of the lubricating oil
composition.
[0095] The following examples are presented to exemplify
embodiments of the invention but are not intended to limit the
invention to the specific embodiments set forth. Unless indicated
to the contrary, all parts and percentages are by weight. All
numerical values are approximate. When numerical ranges are given,
it should be understood that embodiments outside the stated ranges
may still fall within the scope of the invention. Specific details
described in each example should not be construed as necessary
features of the invention.
EXAMPLES
[0096] The following examples are intended for illustrative
purposes only and do not limit in any way the scope of the present
disclosure.
[0097] Isomerization Level (I) and NMR Method
[0098] The isomerization level (I) of the olefin was determined by
hydrogen-1 (1H) NMR. The NMR spectra were obtained on a Bruker
Ultrashield Plus 400 in chloroform-d1 at 400 MHz using TopSpin 3.2
spectral processing software.
[0099] The isomerization level (I) represents the relative amount
of methyl groups (--CH3) (chemical shift 0.3-1.01 ppm) attached to
the methylene backbone groups (.about.CH2-) (chemical shift
1.01-1.38 ppm) and is defined by Equation (1) as shown below,
I=m/(m+n) Equation (I)
where m is NMR integral for methyl groups with chemical shifts
between 0.3.+-.0.03 to 1.01.+-.0.03 ppm, and n is NMR integral for
methylene groups with chemical shifts between 1.01.+-.0.03 to
1.38.+-.0.10 ppm.
[0100] The isomerized level (I) of the alpha olefin is between from
about 0.1 to about 0.4, preferably from about 0.1 to about 0.3,
more preferably from about 0.12 to about 0.3.
[0101] In one embodiment, the isomerization level of the NAO is
about 0.16, and having from about 20 to about 24 carbon atoms.
[0102] In another embodiment, the isomerization level of the NAO is
about 0.26, and having from about 20 to about 24 carbon atoms.
[0103] Provided herein are Tractor Hydraulic Fluid Compositions
which are envisioned for the present disclosure. Examples of the
disclosure will generally include test formulations disclosed in
Table 2 below.
TABLE-US-00002 TABLE 2 TEST COMPOSITIONS Description Wt. % LOB
Sulfonate 0.001 to 5.0 HOB Sulfonate 0.001 to 5.0 HOB Phenate 0.001
to 5.0 Other Additives (Example: Dispersants, 0.01 to 30 Other
Detergents, Antioxidants, Viscosity Improvers, Wear Inhibitors,
Foam Inhibitors, Friction Modifiers, etc.) Base Oils 0.1 to
99.9
[0104] Examples of the disclosure will generally include test
formulations disclosed in Table 3 below.
TABLE-US-00003 TABLE 3 Formulation Compositions Ex 1 Comp A Ex 2
Comp B Ex 3 Comp C Phenate 1 0.012 0 0.020 0 0.040 0 (wt. % Ca)
Phenate 2 0 0.012 0 0.020 0 0.040 (wt. % Ca) LOB 0.024 0.024 0.024
0.024 0.024 0.024 sulfonate (wt. % Ca) HOB 0.240 0.240 0.240 0.240
0.240 0.240 sulfonate (wt. % Ca) Friction 0.75 0.75 0.75 0.75 0.75
0.75 Modifier (wt %) ZnDTP 15 15 15 15 15 15 (mM) Foam 0.02 0.02
0.02 0.02 0.02 0.02 inhibitor (wt %) Dispersant 4.22 4.22 4.22 4.22
4.22 4.22 PMA (wt %) PPD (wt %) 0.2 0.2 0.2 0.2 0.2 0.2 Base oil
11.42 11.42 11.45 11.47 11.45 11.45 (wt %) Phenate 1 is Ca phenate
derived from C20-24 isomerized olefin Phenate 2 is Ca phenate
derived from tetrapropylene
[0105] The test formulations in Table 3 were evaluated in the R20
test which is an axle brake screener test. It is a friction
endurance test that tracks friction coefficients and brake noise at
various friction plate engagement steps that include multiple
pressures and speeds. This test is part of the ZF TE-ML 05E and
TE-ML 05F specifications for axles of off-road vehicles from ZF
Friedrichshafen AG, Friedrichshafen, Germany, and is available
there.
[0106] The results of the R20 test are in Table 4 below.
TABLE-US-00004 TABLE 4 Max Torque Variation at Various Facing
Pressure (MPa) MPa Ex 1 Comp A Ex 2 Comp B Ex 3 Comp C 1.0 836.03
1016.85 921.59 1032.88 436.73 536.66 1.5 1154.23 1293.91 1128.87
1210.25 441.63 676.45 2.0 1183.84 1430.68 1069.86 1311.69 441.26
704.81 2.5 1269.61 1551.67 1191.98 1408.00 438.54 757.37 3.0
1387.19 1586.69 1080.82 1459.35 182.45 698.06 3.5 1316.18 1398.84
378.19 1479.77 87.71 309.99 4.0 656.43 1476.73 419.93 871.95 74.80
102.41
[0107] The R20 friction testing was performed to compare the low
speed brake torque variation performance of formulations containing
Phenate 1 (Ca phenate derived from C20-24 isomerized olefin) versus
analogous formulations containing Phenate 2 (Ca phenate derived
from tetrapropylene). The results of R20 testing demonstrate that
Example formulations 1, 2 and 3 comprising Phenate 1 show reduced
low speed brake torque variation as compared to Comparative
formulations A, B, and C comprising Phenate 2. This means that
formulations containing phenate 1 improved clutch and brake
capacity while maintaining low torque variation at low speed. The
benefit of mitigated low speed brake torque variation is decreased
energy loss and vibration, which correlates to lower risk of damage
to mechanical parts, decreased operator discomfort, and less
tendency for brake noise.
* * * * *