U.S. patent application number 16/021161 was filed with the patent office on 2019-01-03 for lubricating engine oil compositions containing detergent compounds.
The applicant listed for this patent is Chevron Oronite Company LLC, CHEVRON ORONITE SAS, CHEVRON ORONITE TECHNOLOGY B.V.. Invention is credited to Alexander Bowman Boffa, Curtis Bay Campbell, Walter Alexander Hartgers, Seyedeh Mahboobeh Hosseini, Christopher P. Le Deore, Yue-Rong Li, Brendan P. Miller, Xiaomin Helen Tu, Jacob Daniel Ward.
Application Number | 20190002789 16/021161 |
Document ID | / |
Family ID | 63080223 |
Filed Date | 2019-01-03 |
![](/patent/app/20190002789/US20190002789A1-20190103-C00001.png)
United States Patent
Application |
20190002789 |
Kind Code |
A1 |
Boffa; Alexander Bowman ; et
al. |
January 3, 2019 |
LUBRICATING ENGINE OIL COMPOSITIONS CONTAINING DETERGENT
COMPOUNDS
Abstract
The present disclosure generally relates to a lubricating oil
composition comprising an oil of lubricating viscosity, and an
alkylhydroxybenzoate detergent compound.
Inventors: |
Boffa; Alexander Bowman;
(Oakland, CA) ; Hartgers; Walter Alexander;
(Rotterdam, NL) ; Hosseini; Seyedeh Mahboobeh;
(Richmond, CA) ; Ward; Jacob Daniel; (Berkeley,
CA) ; Le Deore; Christopher P.; (Cedex, FR) ;
Miller; Brendan P.; (Richmond, CA) ; Tu; Xiaomin
Helen; (Oakland, CA) ; Campbell; Curtis Bay;
(Hercules, CA) ; Li; Yue-Rong; (Albany,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chevron Oronite Company LLC
CHEVRON ORONITE TECHNOLOGY B.V.
CHEVRON ORONITE SAS |
San Ramon
San Ramon
San Ramon |
CA
CA
CA |
US
US
US |
|
|
Family ID: |
63080223 |
Appl. No.: |
16/021161 |
Filed: |
June 28, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62527211 |
Jun 30, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 159/24 20130101;
C10N 2060/14 20130101; C10N 2040/25 20130101; C10N 2030/02
20130101; C10M 2223/045 20130101; C10N 2030/74 20200501; C10M
129/54 20130101; C10N 2010/04 20130101; C10N 2030/54 20200501; C10N
2010/12 20130101; C10M 2219/046 20130101; C10N 2030/41 20200501;
C10N 2020/071 20200501; C10M 2207/262 20130101; C10M 2215/28
20130101; C10M 2219/068 20130101; C10N 2030/52 20200501; C10M
2207/262 20130101; C10N 2010/04 20130101; C10M 2223/045 20130101;
C10N 2010/04 20130101; C10M 2207/262 20130101; C10N 2010/04
20130101; C10M 2223/045 20130101; C10N 2010/04 20130101 |
International
Class: |
C10M 159/24 20060101
C10M159/24 |
Claims
1. A lubricating oil composition comprising: (a) a major amount of
an oil of lubricating viscosity, and (b) an alkylhydroxybenzoate
compound derived from C.sub.10-C.sub.40 isomerized normal alpha
olefins, wherein the TBN of the alkylhydroxybenzoate detergent is
from 10 to 300 mgKOH/gm on an oil-free basis.
2. The lubricating oil composition of claim 1, further comprising a
molybdenum compound.
3. The lubricating oil composition of claim 3, wherein the
molybdenum compound is a molybdenum succinimide.
4. The lubricating oil composition of claim 1, further comprising a
friction modifier.
5. The lubricating oil composition of claim 4, wherein the friction
modifier is a fatty acid derivative.
6. The lubricating oil composition of claim 5, where the fatty acid
derivative is a fatty acid ester, borated fatty acid ester, or an
amide
7. The lubricating oil composition of claim 1, further comprising a
detergent selected from phenate, sulfonate, salicylate, salixarate,
saligenin, complex detergents and naphthenate detergents.
8. The lubricating oil composition of claim 7, wherein the
detergent is an overbased sulfonate.
9. The lubricating oil composition of claim 1, wherein the
isomerized normal alpha olefin has an isomerization level (I) of
the normal alpha olefin of from about 0.1 to about 0.4.
10. The lubricating oil composition of claim 1, wherein the
isomerized normal alpha olefin has from about 14 to about 28 carbon
atoms per molecule.
11. The alkylhydroxybenzoate detergent of claim 1, wherein the
isomerized normal alpha olefin has from about 18 to about 24 carbon
atoms per molecule.
12. The alkylhydroxybenzoate detergent of claim 1, wherein the
isomerized normal alpha olefin has from about 20 to about 24 carbon
atoms per molecule.
13. The lubricating oil composition of claim 1, wherein the
alkylhydroxybenzoate detergent is an alkylated hydroxybenzoate
detergent.
14. The lubricating oil composition of claim 1, wherein the
alkylhydroxybenzoate detergent is a calcium alkylhydroxybenzoate
detergent.
15. The lubricating oil composition of claim 1, further comprising
a metal dithiophosphate.
16. The lubricating oil composition of claim 15, wherein the metal
dithiophosphate contains a secondary alkyl group.
17. A method of lubricating an engine comprising lubricating said
engine with a lubricating oil composition comprising: (a) a major
amount of an oil of lubricating viscosity, and (b) an
alkylhydroxybenzoate compound derived from C.sub.10-C.sub.40
isomerized normal alfa olefins, wherein the TBN of the
alkylhydroxybenzoate compound is 10-300 mgKOH/gm on an oil-free
basis.
Description
[0001] This application claims the benefit of and priority to U.S.
Provisional Application Ser. No. 62/527,211, filed Jun. 30,
2017.
BACKGROUND OF THE DISCLOSURE
[0002] Neutral and Overbased detergents are well described to
provide lubricating properties. Often such detergent additives are
proportioned with other lubricating additives to provide
lubricating oil compositions that exhibit certain desired
lubricating properties. Metal-containing detergents function both
as detergents to control deposits, and as acid neutralizers or rust
inhibitors, thereby reducing wear and corrosion and extending
engine life. Detergents are utilized in lubricants for these
benefits, but there are drawbacks to their use as well. Detergents
are known to be detrimental to friction performance. Increased
friction is associated with decreased fuel economy so this can be a
drawback as fuel economy improvement is important for environmental
and cost saving reasons.
[0003] A major challenge in engine oil formulation is developing
lubricating oil compositions which simultaneously achieve wear
control and inhibits corrosion, while also achieving improved fuel
economy. Surprisingly, it has been found that lubricants formulated
with alkylhydroxybenzoate detergents derived from isomerized normal
alpha olefins show improvements in oxidation reduction, corrosion
inhibition and friction performance.
SUMMARY OF THE DISCLOSURE
[0004] In accordance with one embodiment of the present disclosure,
there is provided a lubricating oil composition which comprises:
[0005] a. a major amount of an oil of lubricating viscosity, and
[0006] b. an alkylhydroxybenzoate compound derived from
C.sub.10-C.sub.40 isomerized normal alpha olefins, wherein the TBN
of the alkylhydroxybenzoate detergents from 10 to 300 mgKOH/gm on
an oil-free basis. [0007] Also provided is a method of lubricating
an engine comprising lubricating said engine with a lubricating oil
composition comprising: [0008] a. a major amount of an oil of
lubricating viscosity, and [0009] b. an alkylhydroxybenzoate
compound derived from C.sub.10-C.sub.40 isomerized normal alfa
olefins, wherein the TBN of the alkylhydroxybenzoate compound is
10-300 mgKOH/gm on an oil-free basis.
DETAILED DESCRIPTION OF THE DISCLOSURE
[0010] 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.
[0011] 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
[0012] 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.
[0013] A "major amount" means in excess of 50 weight % of a
composition.
[0014] 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.
[0015] "Active ingredients" or "actives" refers to additive
material that is not diluent or solvent.
[0016] All percentages reported are weight % on an active
ingredient basis (i.e., without regard to carrier or diluent oil)
unless otherwise stated.
[0017] The abbreviation "ppm" means parts per million by weight,
based on the total weight of the lubricating oil composition.
[0018] Total base number (TBN) was determined in accordance with
ASTM D2896.
[0019] High temperature high shear (HTHS) viscosity at 150.degree.
C. was determined in accordance with ASTM D4863.
[0020] Kinematic viscosity at 100.degree. C. (KV.sub.100) was
determined in accordance with ASTM D445.
[0021] Cold Cranking Simulator (CCS) viscosity at -35.degree. C.
was determined in accordance with ASTM D5293.
[0022] Noack volatility was determined in accordance with ASTM
D5800Metal--The term "metal" refers to alkali metals, alkaline
earth metals, or mixtures thereof.
[0023] 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.
[0024] 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 the alpha or
primary position of the hydrocarbon chain.
[0025] 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.
[0026] All ASTM standards referred to herein are the most current
versions as of the filing date of the present application.
[0027] In one aspect, the present disclosure is directed to a
lubricating oil composition comprising: [0028] (a) a major amount
of an oil of lubricating viscosity, and [0029] (b) a
alkylhydroxybenzoate compound derived from C.sub.10-C.sub.40
isomerized normal alpha olefins, wherein the alkylhydroxybenzoate
compound has a TBN 10-300 mgKOH/gm on an oil-free basis.
[0030] In another aspect, the lubricating oil composition comprises
a molybdenum compound.
[0031] In another aspect, provided is a method of lubricating an
engine comprising lubricating said engine with lubricating oil
composition comprising: [0032] (a) a major amount of an oil of
lubricating viscosity, and (b) a alkylhydroxybenzoate compound
derived from C.sub.10-C.sub.40isomerized normal alfa olefins,
wherein the TBN of the alkylhydroxybenzoate compound is 10-300
mgKOH/gm on an oil-free basis.
[0033] In another aspect, the present disclosure generally relates
to lubricating oil compositions which are suitable for automotive
engines, motorcycle engines, natural gas engines, dual fuel
engines, railroad locomotive engines, mobile natural gas engines,
and as functional fluids for automotive and industrial
applications.
[0034] Alkylhydroxybenzoate detergent derived from isomerized
Normal Alpha Olefin (NAO)
[0035] In one aspect of the present disclosure, the
alkylhydroxybenzoate detergent derived from C.sub.10-C.sub.40
isomerized NAO has a TBN of from 10 to 300, preferably from 50 to
300, more preferably from 100 to 300, even more preferably from 150
to 300, and most preferably from 175 to 250 mgKOH/gram on active
basis.
[0036] In one aspect of the present disclosure, the
alkylhydroxybenzoate detergent derived from C.sub.10-C.sub.40
isomerized NAO is a Ca alkylhydroxybenzoate detergent.
[0037] In one aspect of the present disclosure, the
alkylhydroxybenzoate detergent derived from C.sub.10-C.sub.40
isomerized NAO can be an alkylated hydroxybenzoate detergent. In a
another embodiment, the detergent can be a salicylate detergent. In
another embodiment, the detergent can be a carboxylate
detergent.
[0038] In one aspect of the present disclosure, the
alkylhydroxybenzoate derived from C.sub.10-C.sub.40 isomerized NAO
having a TBN from 10 to 300 on an oil-free basis may be prepared as
described in U.S. Pat. No. 8,893,499 which is herein incorporated
in its entirety.
[0039] In one aspect of the present disclosure, the
alkylhydroxybenzoate detergent having a TBN from 10 to 300 on an
oil-free basis is made from an alkylphenol having an alkyl group
derived from an isomerized alpha olefin having from about 14 to
about 28 carbon atoms per molecule, preferably from about 20 to
about 24 carbon, or preferably from about 20 to about 28 carbon
atoms per molecule.
[0040] In one aspect of the present disclosure, the
alkylhydroxybenzoate derived from C.sub.10-C.sub.40 isomerized NAO
having a TBN from 10 to 300 on an active basis is made from an
alkylphenol with an alkyl group derived from an isomerized NAO
having an isomerization level (i) from about 0.10 to about 0.40,
preferably from about 0.10 to about 0.35, preferably from about
0.10 to about 0.30, and more preferably from about 0.12 to about
0.30.
[0041] In one aspect of the present disclosure, the
alkylhydroxybenzoate derived from C.sub.10-C.sub.40 isomerized NAO
having a TBN from 10 to 300 on an active basis is made from one or
more alkylphenols with an alkyl group derived from
C.sub.10-C.sub.40 isomerized NAO and one or more alkylphenols with
an alkyl group different from C.sub.10-C.sub.40 isomerized NAO.
[0042] In one aspect of the present disclosure, the isomerized NAO
of the alkylhydroxybenzoate has an isomerization level of about
0.16, and has from about 20 to about 24 carbon atoms.
[0043] In one aspect of the present disclosure, the isomerized NAO
of the alkylhydroxybenzoate has an isomerization level of about
0.26, and has from about 20 to about 24 carbon atoms.
[0044] In one aspect of the present disclosure, the lubricating oil
composition comprises about 0.01 to 2.0 wt. % in terms of Ca
content of the alkylhydroxybenzoate derived from C.sub.10-C.sub.40
isomerized NAO having a TBN from 10 to 300 on an active basis,
preferably 0.1 to 1.0 wt. %, more preferably 0.05 to 0.5 wt. %,
more preferably 0.1 to 0.5 wt. %.
[0045] In one aspect of the present disclosure, the lubricating oil
composition comprising the alkylhydroxybenzoate derived from
C.sub.10-C.sub.40 isomerized NAO having a TBN from 10 to 300 on an
oil-free basis is an automotive engine oil composition, a gas
engine oil composition, a dual fuel engine oil composition, a
mobile gas engine oil composition, or a locomotive engine oil
composition.
[0046] In one aspect of the present disclosure, the lubricating oil
composition comprising the alkylhydroxybenzoate derived from
C.sub.10-C.sub.40 isomerized NAO having a TBN from 10 to 300 on an
oil-free basis is a functional fluid for automotive and industrial
applications, such as transmission oil, hydraulic oil, tractor
fluid, gear oil, and the like.
[0047] In one aspect of the present disclosure, the lubricating oil
composition comprising the alkylhydroxybenzoate derived from
C.sub.10-C.sub.40 isomerized NAO having a TBN from 10 to 300 on an
oil-free basis is a multi-grade oil or mono-grade oil.
[0048] In one aspect of the present disclosure, the lubricating oil
composition comprising the alkylhydroxybenzoate derived from
C.sub.10-C.sub.40 isomerized NAO having a TBN from 10 to 300 on an
oil-free basis lubricates crankcases, gears, as well as
clutches.
Organomolybdenum Compound
[0049] The organomolybdenum compound contains at least molybdenum,
carbon and hydrogen atoms, but may also contain sulfur, phosphorus,
nitrogen and/or oxygen atoms. Suitable organomolybdenum compounds
include molybdenum dithiocarbamates, molybdenum dithiophosphates,
and various organic molybdenum complexes such as molybdenum
carboxylates, molybdenum esters, molybdenum amines, molybdenum
amides, which can be obtained by reacting molybdenum oxide or
ammonium molybdates with fats, glycerides or fatty acids, or fatty
acid derivatives (e.g., esters, amines, amides). The term "fatty"
means a carbon chain having 10 to 22 carbon atoms, typically a
straight carbon chain.
[0050] In one embodiment, the molybdenum amine is a
molybdenum-succinimide complex. Suitable molybdenum-succinimide
complexes are described, for example, in U.S. Pat. No. 8,076,275.
These complexes are prepared by a process comprising reacting an
acidic molybdenum compound with an alkyl or alkenyl succinimide of
a polyamine of structure (3) or (4) or mixtures thereof:
##STR00001##
wherein R is a C.sub.24 to C.sub.350 (e.g., C.sub.70 to C.sub.128)
alkyl or alkenyl group; R' is a straight or branched-chain alkylene
group having 2 to 3 carbon atoms; x is 1 to 11; and y is 1 to
10.
[0051] The molybdenum compounds used to prepare the
molybdenum-succinimide complex are acidic molybdenum compounds or
salts of acidic molybdenum compounds. By "acidic" is meant that the
molybdenum compounds will react with a basic nitrogen compound as
measured by ASTM D664 or D2896. Generally, the acidic molybdenum
compounds are hexavalent. Representative examples of suitable
molybdenum compounds include molybdenum trioxide, molybdic acid,
ammonium molybdate, sodium molybdate, potassium molybdate and other
alkaline metal molybdates and other molybdenum salts such as
hydrogen salts, (e.g., hydrogen sodium molybdate), MoOCl.sub.4,
MoO.sub.2Br.sub.2, Mo.sub.2O.sub.3Cl.sub.6, and the like.
[0052] The succinimides that can be used to prepare the
molybdenum-succinimide complex are disclosed in numerous references
and are well known in the art. Certain fundamental types of
succinimides and the related materials encompassed by the term of
art "succinimide" are taught in U.S. Pat. Nos. 3,172,892;
3,219,666; and 3,272,746. The term "succinimide" is understood in
the art to include many of the amide, imide, and amidine species
which may also be formed. The predominant product however is a
succinimide and this term has been generally accepted as meaning
the product of a reaction of an alkyl or alkenyl substituted
succinic acid or anhydride with a nitrogen-containing compound.
Preferred succinimides are those prepared by reacting a
polyisobutenyl succinic anhydride of about 70 to 128 carbon atoms
with a polyalkylene polyamine selected from triethylenetetramine,
tetraethylenepentamine, and mixtures thereof.
[0053] The molybdenum-succinimide complex may be post-treated with
a sulfur source at a suitable pressure and a temperature not to
exceed 120.degree. C. to provide a sulfurized
molybdenum-succinimide complex. The sulfurization step may be
carried out for a period of from about 0.5 to 5 hours (e.g., 0.5 to
2 hours). Suitable sources of sulfur include elemental sulfur,
hydrogen sulfide, phosphorus pentasulfide, organic polysulfides of
formula R.sub.2S.sub.x where R is hydrocarbyl (e.g., C.sub.1 to
C.sub.10 alkyl) and x is at least 3, C.sub.1 to C.sub.10
mercaptans, inorganic sulfides and polysulfides, thioacetamide, and
thiourea.
[0054] The molybdenum compounds are used in an amount that provides
at least 50 ppm, at least 70 ppm, at least 90 ppm, at least 110
ppm, at least 130 ppm, at least 150 ppm, or at least 200 ppm (e.g.,
50 to 1500 ppm, 70 to 1500 ppm, 90 to 1000 ppm, 110 to 1000 ppm,
130 to 1000 ppm, 150 to 1000 ppm, or 200 to 1000 ppm) by weight of
molybdenum to the lubricating oil composition.
[0055] Friction Modifiers
[0056] The lubricating oil composition disclosed herein can
comprise a friction modifier that can lower the friction between
moving parts. Any friction modifier known by a person of ordinary
skill in the art may be used in the lubricating oil composition.
Non-limiting examples of suitable friction modifiers include fatty
carboxylic acids; derivatives (e.g., alcohol, esters, borated
esters, amides, metal salts and the like) of fatty carboxylic acid;
mono-, di- or tri-alkyl substituted phosphoric acids or phosphonic
acids; derivatives (e.g., esters, amides, metal salts and the like)
of mono-, di- or tri-alkyl substituted phosphoric acids or
phosphonic acids; mono-, di- or tri-alkyl substituted amines; mono-
or di-alkyl substituted amides and combinations thereof. In some
embodiments, the friction modifier is selected from the group
consisting of aliphatic amines, ethoxylated aliphatic amines,
aliphatic carboxylic acid amides, ethoxylated aliphatic ether
amines, aliphatic carboxylic acids, glycerol esters, aliphatic
carboxylic ester-amides, fatty imidazolines, fatty tertiary amines,
wherein the aliphatic or fatty group contains more than about eight
carbon atoms so as to render the compound suitably oil soluble. In
some embodiments, the friction modifier is a fatty acid derivative.
In some embodiments, the fatty acid derivative is a fatty acid
ester, a borated fatty acid ester, or an amide. In other
embodiments, the friction modifier comprises an aliphatic
substituted succinimide formed by reacting an aliphatic succinic
acid or anhydride with ammonia or a primary amine. The amount of
the friction modifier may vary from about 0.01 wt. % to about 10
wt. %, from about 0.05 wt. % to about 5 wt. %, or from about 0.1
wt. % to about 3 wt. %, based on the total weight of the
lubricating oil composition.
[0057] Antiwear Agents
[0058] 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,
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.
[0059] 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.
[0060] In one embodiment, the lubricating oil composition
containing the magnesium salicylate detergent described herein
further comprises an antioxidant compound. In one embodiment, the
antioxidant is a diphenylamine antioxidant. In another embodiment,
the antioxidant is a hindered phenol antioxidant. In yet another
embodiment, the antioxidant is a combination of a diphenylamine
antioxidant and a hindered phenol antioxidant.
[0061] Antioxidants
[0062] 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, and sulfurized
alkylphenols and alkali and alkaline earth metals salts
thereof.
[0063] 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-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; 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).
[0064] 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.
[0065] Antioxidants may be present at 0.01 to 5 wt. % (e.g., 0.1 to
2 wt. %) of the lubricating oil composition.
[0066] Dispersants
[0067] Dispersants maintain in suspension materials resulting from
oxidation during engine operation 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.
[0068] 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.
[0069] 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.
[0070] Particularly preferred ashless dispersants are the
polyisobutenyl succinimides formed from polyisobutenyl succinic
anhydride and a polyalkylene polyamine such as a polyethylene
polyamine 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
bis-succinimide derived from a polyisobutenyl group having a
M.sub.n of 900 to 2500 Daltons.
[0071] As is known in the art, the dispersants may be post-treated
(e.g., with a boronating agent or a cyclic carbonate).
[0072] 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.
[0073] Dispersants may be present at 0.1 to 10 wt. % (e.g., 2 to 5
wt. %) of the lubricating oil composition.
[0074] Additional Detergents
[0075] The lubricating oil composition of the present invention can
further contain one or more overbased detergents having a TBN of
10-800, 10-700, 30-690, 100-600, 150-600, 150-500, 200-450 mg KOH/g
on an actives basis.
[0076] In some embodiments, the detergents that may be used include
oil-soluble sulfonate, overbased sulfonate, non-sulfur containing
phenate, sulfurized phenates, salixarate, salicyiate, 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.
[0077] 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.
[0078] 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.
[0079] 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.
[0080] 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.
[0081] 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.
[0082] 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.
[0083] 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.
[0084] 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.
[0085] Metal salts of phenols and sulfurized phenols, which are
sulfurized phenate detergents, are prepared by reaction with an
appropriate metal compound such as an oxide or hydroxide and
neutral or overbased products may be obtained by methods well known
in the art. Sulfurized phenols may be prepared by reacting a phenol
with sulfur or a sulfur containing compound such as hydrogen
sulfide, sulfur monohalide or sulfur dihalide, to form products
which are generally mixtures of compounds in which 2 or more
phenols are bridged by sulfur containing bridges.
[0086] Additional details regarding the general preparation of
sulfurized phenates can be found in, for example, U.S. Pat. Nos.
2,680,096; 3,178,368, 3,801,507, and 8,580,717 the contents of
which are incorporated herein by reference.
[0087] Considering now in detail, the reactants and reagents used
in the present process, first all allotropic forms of sulfur can be
used. The sulfur can be employed either as molten sulfur or as a
solid (e.g., powder or particulate) or as a solid suspension in a
compatible hydrocarbon liquid.
[0088] It is desirable to use calcium hydroxide as the calcium base
because of its handling convenience versus, for example, calcium
oxide, and also because it affords excellent results. Other calcium
bases can also be used, for example, calcium alkoxides.
[0089] Suitable alkylphenols which can be used are those wherein
the alkyl substituents contain a sufficient number of carbon atoms
to render the resulting overbased sulfurized calcium alkylphenate
composition oil-soluble. Oil solubility may be provided by a single
long chain alkyl substitute or by a combination of alkyl
substituents. Typically, the alkylphenol used will be a mixture of
different alkylphenols, e.g., C.sub.20 to C.sub.24 alkylphenol.
[0090] In one embodiment, suitable alkyl phenolic compounds will be
derived from isomerized alpha olefin alkyl groups having from about
10 to about 40 carbon atoms per molecule, having an isomerized
level (1) of the alpha olefin between from about 0.1 to about 0.4.
In one embodiment, suitable alkyl phenolic compounds will be
derived from alkyl groups which are branched olefinic propylene
oligomers or mixture thereof having from about 9 to about 80 carbon
atoms. In one embodiment, the branched olefinic propylene oligomer
or mixtures thereof have from about 9 to about 40 carbon atoms. In
one embodiment, the branched olefinic propylene oligomer or
mixtures thereof have from about 9 to about 18 carbon atoms. In one
embodiment, the branched olefinic propylene oligomer or mixtures
thereof have from about 9 to about 12 carbon atoms.
[0091] In one embodiment, suitable alkyl phenolic compounds
comprise distilled cashew nut shell liquid (CNSL) or hydrogenated
distilled cashew nut shell liquid. Distilled CNSL is a mixture of
biodegradable meta-hydrocarbyl substituted phenols, where the
hydrocarbyl group is linear and unsaturated, including cardanol.
Catalytic hydrogenation of distilled CNSL gives rise to a mixture
of meta-hydrocarbyl substituted phenols predominantly rich in
3-pentadecylphenol.
[0092] The alkylphenols can be para-alkylphenols, meta-alkylphenols
or ortho alkylphenols. Since it is believed that p-alkylphenols
facilitate the preparation of highly overbased calcium sulfurized
alkylphenate where overbased products are desired, the alkylphenol
is preferably predominantly a para alkylphenol with no more than
about 45 mole percent of the alkylphenol being ortho alkylphenols;
and more preferably no more than about 35 mole percent of the
alkylphenol is ortho alkylphenol. Alkyl-hydroxy toluenes or
xylenes, and other alkyl phenols having one or more alkyl
substituents in addition to at least one long chained alkyl
substituent can also be used. In the case of distilled cashew nut
shell liquid, the catalytic hydrogenation of distilled CNSL gives
rise to a mixture of meta-hydrocarbyl substituted phenols.
[0093] In one embodiment, the one or more overbased detergent can
be a complex or hybrid detergent which is known in the art as
comprising a surfactant system derived from at least two
surfactants described above.
[0094] Generally, the amount of the detergent can be from about
0.001 wt. % to about 50 wt. %, or from about 0.05 wt. % to about 25
wt. %, or from about 0.1 wt. % to about 20 wt. %, or from about
0.01 to 15 wt. % based on the total weight of the lubricating oil
composition.
[0095] Additional Co-Additives
[0096] 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.
[0097] 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.
[0098] 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.
crankcase motor oils. 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.
[0099] 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.
[0100] 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.
[0101] Oil of Lubricating Viscosity
[0102] 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.
[0103] 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.
[0104] Synthetic lubricating oils include hydrocarbon oils such as
polymerized and interpolymerized olefins (e.g., polybutylenes,
polypropylenes, propylene-isobutylene copolymers, chlorinated
polybutylenes, poly(1-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.
[0105] 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.
[0106] Esters useful as synthetic oils also include those made from
C.sub.5 to C.sub.12 monocarboxylic acids and polyols, and polyol
ethers such as neopentyl glycol, trimethylolpropane,
pentaerythritol, dipentaerythritol and tripentaerythritol.
[0107] The base oil may be derived from Fischer-Tropsch synthesized
hydrocarbons. Fischer-Tropsch synthesized hydrocarbons are made
from synthesis gas containing H.sub.2 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.
[0108] 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.
[0109] 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.
[0110] 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.
[0111] 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.
[0112] 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.
[0113] 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 0 W, 0 W-8, 0 W-12, 0 W-16, 0 W-20, 0 W-26, 0
W-30, 0 W-40, 0 W-50, 0 W-60, 5 W, 5 W-20, 5 W-30, 5 W-40, 5 W-50,
5 W-60, 10 W, 10 W-20, 10 W-30, 10 W-40, 10 W-50, 15 W, 15 W-20, 15
W-30, 15 W-40, 30, 40 and the like.
[0114] Lubricating Oil Compositions
[0115] In general, the level of sulfur in the lubricating oil
compositions of the present invention is less than or equal to
about 0.7 wt. %, based on the total weight of the lubricating oil
composition, e.g., a level of sulfur of about 0.01 wt. % to about
0.70 wt. %, 0.01 to 0.6 wt. %, 0.01 to 0.5 wt. %, 0.01 to 0.4 wt.
%, 0.01 to 0.3 wt. %, 0.01 to 0.2 wt. %, 0.01 wt. % to 0.10 wt. %.
In one embodiment, the level of sulfur in the lubricating oil
compositions of the present invention is less than or equal to
about 0.60 wt. %, less than or equal to about 0.50 wt. %, less than
or equal to about 0.40 wt. %, less than or equal to about 0.30 wt.
%, less than or equal to about 0.20 wt. %, less than or equal to
about 0.10 wt. % based on the total weight of the lubricating oil
composition.
[0116] In one embodiment, the levels of phosphorus in the
lubricating oil compositions of the present invention is less than
or equal to about 0.12 wt. %, based on the total weight of the
lubricating oil composition, e.g., a level of phosphorus of about
0.01 wt. % to about 0.12 wt. %. In one embodiment, the levels of
phosphorus in the lubricating oil compositions of the present
invention is less than or equal to about 0.11 wt. %, based on the
total weight of the lubricating oil composition, e.g., a level of
phosphorus of about 0.01 wt. % to about 0.11 wt. %. In one
embodiment, the levels of phosphorus in the lubricating oil
compositions of the present invention is less than or equal to
about 0.10 wt. %, based on the total weight of the lubricating oil
composition, e.g., a level of phosphorus of about 0.01 wt. % to
about 0.10 wt. %. In one embodiment, the levels of phosphorus in
the lubricating oil compositions of the present invention is less
than or equal to about 0.09 wt. %, based on the total weight of the
lubricating oil composition, e.g., a level of phosphorus of about
0.01 wt. % to about 0.09 wt. %. In one embodiment, the levels of
phosphorus in the lubricating oil compositions of the present
invention is less than or equal to about 0.08 wt. %, based on the
total weight of the lubricating oil composition, e.g., a level of
phosphorus of about 0.01 wt. % to about 0.08 wt. %. In one
embodiment, the levels of phosphorus in the lubricating oil
compositions of the present invention is less than or equal to
about 0.07 wt. %, based on the total weight of the lubricating oil
composition, e.g., a level of phosphorus of about 0.01 wt. % to
about 0.07 wt. %. In one embodiment, the levels of phosphorus in
the lubricating oil compositions of the present invention is less
than or equal to about 0.05 wt. %, based on the total weight of the
lubricating oil composition, e.g., a level of phosphorus of about
0.01 wt. % to about 0.05 wt. %.
[0117] In one embodiment, the level of sulfated ash produced by the
lubricating oil compositions of the present invention is less than
or equal to about 1.60 wt. % as determined by ASTM D 874, e.g., a
level of sulfated ash of from about 0.10 to about 1.60 wt. % as
determined by ASTM D 874. In one embodiment, the level of sulfated
ash produced by the lubricating oil compositions of the present
invention is less than or equal to about 1.00 wt. % as determined
by ASTM D 874, e.g., a level of sulfated ash of from about 0.10 to
about 1.00 wt. % as determined by ASTM D 874. In one embodiment,
the level of sulfated ash produced by the lubricating oil
compositions of the present invention is less than or equal to
about 0.80 wt. % as determined by ASTM D 874, e.g., a level of
sulfated ash of from about 0.10 to about 0.80 wt. % as determined
by ASTM D 874. In one embodiment, the level of sulfated ash
produced by the lubricating oil compositions of the present
invention is less than or equal to about 0.60 wt. % as determined
by ASTM D 874, e.g., a level of sulfated ash of from about 0.10 to
about 0.60 wt. % as determined by ASTM D 874.
[0118] 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
[0119] The following examples are intended for illustrative
purposes only and do not limit in any way the scope of the present
disclosure.
[0120] The isomerization level was measured by an NMR method.
Isomerization Level (1) and NMR Method
[0121] 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.
[0122] The isomerization level (I) represents the relative amount
of methyl groups (--CH.sub.3) (chemical shift 0.30-1.01 ppm)
attached to the methylene backbone groups (--CH.sub.2--) (chemical
shift 1.01-1.38 ppm) and is defined by Equation (1) as shown
below,
I=m(m+n) Equation (1)
where m is NMR integral for methyl groups with chemical shifts
between 0.30.+-.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.
Baseline Formulation 1
[0123] A 15 W-40 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0124] (1) an ethylene carbonate
post-treated bis-succinimide; [0125] (2) a mixture of a primary
zinc dialkyldithiophosphate and a secondary zinc
dialkyldithiophosphate; [0126] (3) a diphenylamine antioxidant;
[0127] (4) 45 ppm in terms of molybdenum content of a
sulfur-containing molybdenum succinimide; and [0128] (5) a foam
inhibitor.
Baseline Formulation 2
[0129] A 15 W-40 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0130] (1) an ethylene carbonate
post-treated bis-succinimide; [0131] (2) a secondary zinc
dialkyldithiophosphate; [0132] (3) a diphenylamine antioxidants;
[0133] (4) 380 ppm in terms of molybdenum content of a
sulfur-containing molybdenum succinimide; and [0134] (5) a foam
inhibitor.
Baseline Formulation 3
[0135] A 15 W-40 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0136] (1) an ethylene carbonate
post-treated bis-succinimide; [0137] (2) a secondary zinc
dialkyldithiophosphate; [0138] (3) a diphenylamine antioxidant;
[0139] (4) 380 ppm in terms of molybdenum content of a sulfur-free
molybdenum succinimide; and [0140] (5) a foam inhibitor.
Example A
[0141] An alkylated phenol and alkylated Ca alkylhydroxybenzoate
were prepared in substantially the same manner as in U.S. Pat. No.
8,993,499 using a C.sub.20-24 isomerized normal alpha olefin
available from CP Chem. The isomerization level of the alpha olefin
is about 0.16. The resulting alkylated alkylhydroxybenzoate
composition has a TBN of about 225 mgKOH/gm and Ca content of 8 wt.
% on an oil-free basis.
Example B
[0142] An alkylated phenol and alkylated Ca alkylhydroxybenzoate
were prepared in substantially the same manner as in U.S. Pat. No.
8,993,499 using a C.sub.20-24 isomerized normal alpha olefin
available from CP Chem. The isomerization level of the alpha olefin
is about 0.16. The resulting alkylated alkylhydroxybenzoate
composition has a TBN of about 120 mgKOH/gm and Ca content of 4.2
wt. % on an oil-free basis.
Comparative Example A
[0143] An alkylated phenol and alkylated Ca alkylhydroxybenzoate
were prepared in substantially the same manner as in U.S. Pat. No.
8,030,258 using a C.sub.20-28 normal alpha olefin available from CP
Chem. The resulting alkylated alkylhydroxybenzoate composition has
a TBN of about 230 and Ca content about 8 wt. % on an oil-free
basis.
Comparative Example B
[0144] An alkylated alkylhydroxybenzoate was prepared from an
alkylphenol with an alkyl group derived from C.sub.14-C.sub.18
normal alpha olefin and a TBN about 300 mgKOH/gm and Ca content
about 10.6 wt. % on an oil-free basis.
Comparative Example C
[0145] An alkylated alkylhydroxybenzoate was prepared from an
alkylphenol with an alkyl group derived from C.sub.20-C.sub.28
normal alpha olefin and a TBN about 115 mgKOH/gm and Ca content
about 4 wt. % on an oil-free basis.
Comparative Example D
[0146] A highly overbased Ca Sulfonate having a TBN about 700
mgKOH/gm and Ca content about 26 wt. % on an oil-free basis.
Example 1
[0147] To baseline formulation 1 was added 0.35 wt. % in terms of
Ca content of a Ca alkylhydroxybenzoate detergent of Example A. The
lubricating oil composition has 0.21 wt % of S, 0.1 wt % of P, and
1.3 wt % of ash.
Comparative Example 1
[0148] To baseline formulation 1 was added 0.35 wt. % in terms of
Ca content of a Ca alkylhydroxybenzoate detergent of Comparative
Example A. The lubricating oil composition has 0.22 wt % of S, 0.1
wt % of P, and 1.3 wt % of ash.
Comparative Example 2
[0149] To baseline formulation 1 was added 0.35 wt. % in terms of
Ca content of a Ca alkylhydroxybenzoate of Comparative Example B.
The lubricating oil composition has 0.22 wt % of S, 0.1 wt % of P,
and 1.3 wt % of ash.
Example 2
[0150] To baseline formulation 2 was added 0.35 wt. % in terms of
Ca content of a Ca alkylhydroxybenzoate of Example A. The
lubricating oil composition has 0.17 wt % of S, 0.07 wt % of P, and
1.3 wt % of ash.
Comparative Example 3
[0151] To baseline formulation 2 was added 0.35 wt. % in terms of
Ca content of a Ca alkylhydroxybenzoate of Comparative Example B.
The lubricating oil composition has 0.16 wt % of S, 0.07 wt % of P,
and 1.3 wt % of ash.
Example 3
[0152] To baseline formulation 3 was added 0.35 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Example A. The lubricating
oil composition has 0.17 wt % of S, 0.07 wt % of P, and 1.3 wt % of
ash.
Comparative Example 4
[0153] To baseline formulation 3 was added 0.35 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Comparative Example B. The
lubricating oil composition has 0.16 wt % of S, 0.07 wt % of P, and
1.3 wt % of ash.
[0154] Examples 1 to 3, and Comparative Examples 1 to 4 were
evaluated in the TEOST MHT4 and HTCBT tests described below.
Results are in Table 2.
TEOST MHT4
[0155] The ASTM D7097 TEOST MHT4 test is designed to predict the
deposit-forming tendencies of engine oil in the piston ring belt
and upper piston crown area. Correlation has been shown between the
TEOST MHT procedure and the TU3MH Peugeot engine test in deposit
formation. This test determines the mass of deposit formed on a
specially constructed test rod exposed to repetitive passage of 8.5
g of engine oil over the rod in a thin film under oxidative and
catalytic conditions at 285 deg C. Deposit-forming tendencies of an
engine oil under oxidative conditions are determined by circulating
an oil-catalyst mixture comprising a small sample (8.4 g) of the
oil and a very small (0.1 g) amount of an organo-metallic catalyst.
This mixture is circulated for 24 hours in the TEOST MHT instrument
over a special wire-wound depositor rod heated by electrical
current to a controlled temperature of 285 deg C. at the hottest
location on the rod. The rod is weighed before and after the test.
Deposit weight of 35 mg is considered as pass/fail criteria.
HTCBT
[0156] The ASTM D6594 HTCBT test is used to test diesel engine
lubricants to determine their tendency to corrode various metals,
specifically alloys of lead and copper commonly used in cam
followers and bearings. Four metal specimens of copper, lead, tin
and phosphor bronze are immersed in a measured amount of engine
oil. The oil, at an elevated temperature (170.degree. C.), is blown
with air (5 l/h) for a period of time (168 h). When the test is
completed, the copper specimen and the stressed oil are examined to
detect corrosion and corrosion products, respectively. The
concentrations of copper, lead, and tin in the new oil and stressed
oil and the respective changes in metal concentrations are
reported. To be a pass the concentration of lead should not exceed
120 ppm and the copper 20 ppm.
TABLE-US-00002 TABLE 2 HTCBT and TEOST MHT4 HTCBT (lead in ppm)
TEOST MHT4 Example 1 6 25.7 Comparative Ex 1 32 25.2 Comparative Ex
2 68 74.6 Example 2 14 11.8 Comparative Ex 3 104 33.4 Example 3 17
14.8 Comparative Ex 4 110 24.9
[0157] The Ca alkylhydroxybenzoate derived from C.sub.20-C.sub.24
isomerized NAO has surprisingly better corrosion inhibition and
deposit control performance than the Ca alkylhydroxybenzoate
derived from non-isomerized NAO at equal Ca level. This effect is
enhanced in the presence of an effective level of a molybdenum
compound.
Baseline Formulation 4
[0158] A 5 W-20 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0159] (1) an ethylene carbonate
post-treated bis-succinimide; [0160] (2) a borated bis-succinimide
dispersant; [0161] (3) a mixture of a primary zinc
dialkyldithiophosphate and a secondary zinc dialkyldithiophosphate;
[0162] (4) a mixture of molybdenum succinimide and diphenylamine
antioxidants; and [0163] (5) a foam inhibitor.
Example 4
[0164] To baseline formulation 4 was added 0.18 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Example A. The lubricating
oil composition has 0.16 wt % of S, 0.077 wt % of P, and 0.75 wt %
of ash.
Example 5
[0165] To baseline formulation 4 was added 0.18 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Example A and 68 ppm in
terms of Boron content of a borated glycerol monooleate (Glymo)
friction modifier. The lubricating oil composition has 0.16 wt % of
S, 0.077 wt % of P, and 0.76 wt % of ash.
Comparative Example 8
[0166] To baseline formulation 4 was added 0.18 wt % in terms of Ca
content of a highly overbased Ca sulfonate detergent and 68 ppm in
terms of B content of a borated glycerol monooleate (Glymo)
friction modifier. The lubricating oil composition has 0.18 wt % of
S, 0.077 wt % of P, and 0.75 wt % of ash.
Comparative Example 9
[0167] To baseline formulation 4 was added 0.18 wt % in terms of Ca
content of Comparative Example D. The lubricating oil composition
has 0.18 wt % of S, 0.077 wt % of P, and 0.76 wt % of ash.
MTM Test
[0168] Examples 4 to 5, and Comparative Examples 8 and 9 were
tested for friction performance in a Mini-Traction Machine (MTM)
bench test. The MTM is manufactured by PCS Instruments and operates
with a ball (0.75 inches 8620 steel ball) loaded against a rotating
disk (52100 steel). The conditions employ a load of approximately
10-30 Newtons, a speed of approximately 10-2000 mm/s and a
temperature of approximately 125-150.degree. C. In this bench test,
the boundary friction performance of a formulation under a
rolling/sliding contact is measured by the low speed traction
coefficient. The low speed traction coefficient is the average
traction coefficient of the second Stribeck between 15 and 20 mm/s.
Lower low speed traction coefficients correspond to better boundary
friction performance of the oil. Results are in Table 3.
TABLE-US-00003 TABLE 3 MTM Test Low Speed Traction Coefficient
Example 4 0.1268 Example 5 0.0885 Comparative Example 8 0.1150
Comparative Example 9 0.1269
[0169] The Ca alkylhydroxybenzoate derived from C.sub.20-C.sub.24
isomerized NAO has similar boundary friction performance to the
highly overbased Ca Sulfonate at equal Ca level. However, the
combination of the alkylhydroxybenzoate derived from
C.sub.20-C.sub.24 isomerized NAO and a friction modifier has
significantly better boundary friction performance than the
combination of the highly overbased Ca Sulfonate and a friction
modifier or the alkylhydroxybenzoate alone, indicating a
synergistic effect between the alkylhydroxybenzoate and the
friction modifier.
Baseline Formulation 5
[0170] A railroad lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0171] (1) an ethylene carbonate
post-treated bis-succinimide; [0172] (2) a mixture of phenate
detergents [0173] (3) a mixture of Moly succinimide and
diphenylamine antioxidants; [0174] (4) a friction modifier [0175]
(5) a foam inhibitor. [0176] (6) a viscosity modifier
Example 6
[0177] To baseline formulation 5 was added 0.05 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Example A.
Comparative Example 10
[0178] To baseline formulation 5 was added 0.04 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Comparative Example A.
[0179] Example 6 and Comparative Example 10 were evaluated in the
B2-7 Oxidation Test and the B72-2 Ali Silver Lubricity Test as
described below. B2-7 Test
[0180] The B2-7 test is an oxidation test with the following
conditions:
TABLE-US-00004 UP Oxidation (B2) Temp 149 C. (300 F.) Duration 96
hr Coupons Cu, Fe, Pb Flow oxygen Replenishing oil At 48 hr (50 mL)
72 hr (50 mL) Comments Trend data of BN, AN, pH and Pb ppm
[0181] According to the B2-7 test, the oil to be tested is heated
at 300.degree. F. for 96 hours with bubbling of oxygen. Copper,
iron and lead coupons are suspended in the oil. Fifty milliliter
samples are taken at 48, 72 and 96 hours. The samples at 48 and 72
hours are replenished with fresh oil. The oil test samples are
evaluated for base number, acid number, pH and lead.
[0182] Comparative Example 10 and Example 6 of the invention were
evaluated for Total Base Number (TBN) decrease. The results are in
table 4.
TABLE-US-00005 TABLE 4 B2-7 Test TBN D4739 Comparative Example 10
Example 6 0 hr 9.70 9.64 48 hr 6.50 6.76 72 hr 6.21 6.49 96 hr 5.98
6.22 TBN decrease 3.72 3.42
[0183] Higher numbers for TBN decrease indicate greater depletion
of the base in the oil and are considered less favorable. An oil
for extended use in a locomotive diesel engine will ideally retain
TBN.
[0184] The results show that the Ca alkylhydroxybenzoate detergent
derived from C.sub.20-C.sub.24 isomerized NAO provide better BN
retention when compared with the Ca alkylhydroxybenzoate detergent
derived from non-isomerized NAO, meaning better protection of the
engine.
Baseline Formulation 6
[0185] A 5 W-30 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0186] (1) a borated bis-succinimide;
[0187] (2) an ethylene carbonate-treated bissuccinimide; [0188] (3)
a highly overbased Ca sulfonate detergent [0189] (4) a mixture of a
primary zinc dialkyldithiophosphate and a secondary zinc
dialkyldithiophosphate; [0190] (5) a mixture of Moly succinimide
and diphenylamine antioxidants; [0191] (6) a friction modifier
[0192] (7) a foam inhibitor [0193] (8) a pour point depressant
[0194] (9) a viscosity modifier
Example 7
[0195] To baseline formulation 6 was added 0.1 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Example B.
Comparative Example 11
[0196] To baseline formulation 6 was added 0.1 wt % in terms of Ca
content of a Ca alkylhydroxybenzoate of Comparative Example C.
[0197] Example 7 and Comparative Example 11 were evaluated in the
MRV test as described below.
MRV (Mini Rotary Viscometer)
[0198] The ASTM D4684 MRV test covers the measurement of the yield
stress (0<Y<35 max) and viscosity (60,000 cp max) of engine
oils after cooling at controlled rates over a period not exceeding
45 h to a final test temperature between -10 and -40.degree. C. In
the MRV test an engine oil sample is held at 80.degree. C. and then
cooled at a programmed cooling rate to a final test temperature. A
low torque is applied to the rotor shaft to measure the yield
stress. A higher torque is then applied to determine the apparent
viscosity of the sample. The viscosity measurements are made at
shear stress of 525 Pa over a shear rate of 0.4 to 15 s.sup.-1.
TABLE-US-00006 TABLE 5 MRV Test @-35 C. (ASTM D-4684) Apparent
Viscosity (cP) Yield Stress (Pa) Example 7 43100 <175
Comparative 11 Frozen >350
[0199] The Ca alkylhydroxybenzoate derived from C.sub.20-C.sub.24
isomerized NAO has surprisingly better low temperature performance
than the Ca alkylhydroxybenzoate derived from non-isomerized NAO at
equal Ca level.
Baseline Formulation 7
[0200] A 5 W-20 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0201] (1) a borated bis-succinimide;
[0202] (2) an ethylene carbonate-treated bissuccinimide; [0203] (3)
a mixture of a primary zinc dialkyldithiophosphate and a secondary
zinc dialkyldithiophosphate; [0204] (4) a mixture of Moly
succinimide and diphenylamine antioxidants; [0205] (5) a friction
modifier [0206] (6) a foam inhibitor [0207] (7) a pour point
depressant [0208] (8) a viscosity modifier
Example 8
[0208] [0209] (9) To baseline formulation 7 was added 0.06 wt % in
terms of Ca content of a Ca alkylhydroxybenzoate of Example A and
0.12 wt % in terms of Ca content of Comparative Example D
Example 9
[0209] [0210] (10) To baseline formulation 7 was added 0.12 wt % in
terms of Ca content of a Ca alkylhydroxybenzoate of Example A and
0.06 wt % in terms of Ca content of Comparative Example D
Comparative Example 12
[0210] [0211] (11) To baseline formulation 7 was added 0.18 wt % in
terms of Ca content of a Ca alkylhydroxybenzoate of Example A.
Comparative Example 13
[0211] [0212] (12) To baseline formulation 7 was added 0.18 wt % in
terms of Ca content of Comparative Example D. [0213] (13) Example
8, 9 and Comparative Example 12 and 13 were evaluated in the TE 77
test as described below.
Plint TE 77 High Frequency Friction Machine
[0214] Boundary friction coefficient measurements for the Examples
8 and 9, and Comparative Examples 12 and 13 were obtained using a
Plint TE-77 High Frequency Friction Machine (commercially available
from Phoenix Tribology).
[0215] A 5 mL sample of test oil was placed in the apparatus for
each test. The TE-77 was run at 100.degree. C. and 56N of load was
placed on the testing specimen. The reciprocating speed was swept
from 10 Hz to 1 Hz, and coefficient of friction data was collected
throughout the test. The friction coefficient measurements are
shown in Table 6.
TABLE-US-00007 TABLE 6 Plint TE 77 Example Example Comp Example
Comp Example 8 9 12 13 1 Hz 0.01 0.01 0.06 0.02 2 Hz 0.01 0.01 0.06
0.02 3 Hz 0.01 0.01 0.07 0.02 4 Hz 0.01 0.02 0.07 0.04 5 Hz 0.01
0.03 0.07 0.06 6 Hz 0.02 0.05 0.08 0.08 7 Hz 0.05 0.07 0.08 0.10 8
Hz 0.07 0.08 0.08 0.12 9 Hz 0.09 0.09 0.09 0.13 10 Hz 0.10 0.08
0.08 0.14
[0216] Coefficient of friction data collected for these oils at
reciprocating speeds of 1 to 2 Hz are in a boundary friction
regime.
[0217] The boundary friction regime is an important consideration
in the design of low viscosity engine oils. Boundary friction
occurs when the fluid film separating two surfaces becomes thinner
than the height of asperities on the surfaces. The resulting
surface to surface contact creates undesirable high friction and
poor fuel economy in an engine. Boundary friction in an engine can
occur under high loads, low engine speeds and at low oil
viscosities. Low viscosity engine oils make the engine more
susceptible to operating in boundary friction conditions due to the
oil's thinner, less robust film. Because additives--not base
oil--influence the coefficient of friction under boundary
conditions, additives that demonstrate lower coefficients of
friction under boundary conditions in the TE-77 will give superior
fuel economy in a low viscosity oil in an engine.
[0218] Based on the boundary friction regime results from Examples
8 and 9, it is evident that there is synergistic effect when the
alkylhydroxybenzoate derived from isomerized normal alpha olefin is
used together with the overbased Ca sulfonate.
Baseline Formulation 8
[0219] A 5 W-30 lubricating oil composition was prepared that
contained a major amount of a base oil of lubricating viscosity and
the following additives: [0220] (1) an ethylene carbonate-treated
bissuccinimide; [0221] (2) a highly overbased Ca sulfonate
detergent [0222] (3) a secondary zinc dialkyldithiophosphate;
[0223] (4) a diphenylamine antioxidant [0224] (5) a foam inhibitor
[0225] (6) a pour point depressant [0226] (7) a viscosity
modifier
Example 10
[0226] [0227] (8) To baseline formulation 8 was added 0.2 wt % in
terms of Ca content of a Ca alkylhydroxybenzoate of Example A.
Comparative Example 13
[0228] (9) To baseline formulation 8 was added 0.2 wt % in terms of
Ca content of a Ca alkylhydroxybenzoate of Comparative Example
B.
[0229] Sequence IVA Test
[0230] The lubricating oil compositions of Example 10 and
Comparative Example 13 were evaluated for valve tram wear in a
gasoline engine: Sequence IVA, ASTM D 6891, Average cam wear (7
position average, .mu.m). The passing limit for this test is 90
.mu.m maximum
TABLE-US-00008 TABLE 7 Sequence IVA Test Example 10 Comp Example 13
Camshaft Wear (.mu.m) 67 96
[0231] The Ca alkylhydroxybenzoate derived from C.sub.20-C.sub.24
isomerized NAO has surprisingly better valve tram wear performance
than the Ca alkylhydroxybenzoate derived from non-isomerized NAO at
equal Ca level.
* * * * *