U.S. patent application number 15/562672 was filed with the patent office on 2018-12-13 for lubricants leading to better equipment cleanliness.
The applicant listed for this patent is BASF SE. Invention is credited to Robert BACCHI, Mary DERY, MURIEL ECORMIER, Thomas HAYDEN, Thomas RUEHLE, Markus SCHERER.
Application Number | 20180355270 15/562672 |
Document ID | / |
Family ID | 52807654 |
Filed Date | 2018-12-13 |
United States Patent
Application |
20180355270 |
Kind Code |
A1 |
ECORMIER; MURIEL ; et
al. |
December 13, 2018 |
LUBRICANTS LEADING TO BETTER EQUIPMENT CLEANLINESS
Abstract
The present invention relates to the field of lubricants. In
particular, the present invention is directed to the use of
lubricant compositions comprising a synthetic ester having an
Iodine value lower than 10 g I/100 g measured according to DGF CV
11b for the reduction of deposit formation.
Inventors: |
ECORMIER; MURIEL; (Mannheim,
DE) ; SCHERER; Markus; (Mannheim, DE) ;
HAYDEN; Thomas; (Wappingers Falls, NY) ; DERY;
Mary; (Putnam Valley, NY) ; BACCHI; Robert;
(Highland, NY) ; RUEHLE; Thomas; (Mannheim,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BASF SE |
Ludwigshafen |
|
DE |
|
|
Family ID: |
52807654 |
Appl. No.: |
15/562672 |
Filed: |
March 29, 2016 |
PCT Filed: |
March 29, 2016 |
PCT NO: |
PCT/EP2016/056795 |
371 Date: |
September 28, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 2207/026 20130101;
C10M 2207/2825 20130101; C10N 2040/25 20130101; C10M 129/74
20130101; C10M 2207/282 20130101; C10M 101/00 20130101; C10N
2030/54 20200501; C10N 2030/10 20130101; C10N 2040/135 20200501;
C10N 2030/74 20200501; C10M 2203/1025 20130101; C10N 2030/04
20130101; C10M 129/68 20130101; C10M 2207/283 20130101; C10M 129/72
20130101; C10M 2203/1006 20130101; C10M 105/36 20130101; C10N
2040/255 20200501; C10M 111/02 20130101; C10N 2040/12 20130101;
C10M 2203/003 20130101; C10N 2030/02 20130101; C10M 2203/1025
20130101; C10N 2020/02 20130101; C10M 2203/1025 20130101; C10N
2020/02 20130101 |
International
Class: |
C10M 111/02 20060101
C10M111/02; C10M 101/00 20060101 C10M101/00; C10M 105/36 20060101
C10M105/36 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 30, 2015 |
EP |
15161684.4 |
Claims
1-15. (canceled)
16. Use of a lubricating composition for reducing the formation of
deposits, wherein the composition comprises (i) at least one
lubricating base oil, and (ii) at least one synthetic ester having
an Iodine value lower than 10 g I/100 g measured according to DGF
C-V 11b.
17. Use according to claim 16, wherein the synthetic ester is
selected from (a) a diester of a dicarboxylic acid, (b) a polyol
ester, or (c) mixtures thereof.
18. Use according to claim 16, wherein the diester of the
dicarboxylic acid is selected form the group consisting of
di-(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof.
19. Use according to claim 16, wherein the lubricating base oil is
selected from Group I, Group II, Group III base oils according to
the definition of the API, or mixtures thereof.
20. Use according to claim 16, wherein the composition further
comprises one or more other additives selected from the group
consisting of viscosity index improvers, polymeric thickeners,
antioxidants, corrosion inhibitors, detergents, dispersants,
anti-foam agents, dyes, extreme pressure additives, antiwear
additives, friction modifiers, metal deactivators, pour point
depressants and the like.
21. Use according to claim 16 wherein (a) the deposits are
determined according to the TEOST MHT D7097 test, or (b) the
deposits are measured according to ASTM D4310.
22. Use according to claim 16, wherein the oxidation stability
measured according to HPDSC test is increased compared to a
composition wherein the synthetic ester has been replaced by a
lubricant base oil selected from Group I, Group II, Group III base
oils or mixtures thereof.
23. Use according to claim 16, wherein the Noack volatility
measured according to ASTM D5800 is decreased compared to a
composition wherein the synthetic ester has been replaced by a
lubricant base oil selected from Group I, Group II, Group III base
oils or mixtures thereof, and wherein preferably the Noack
volatility is below 12% weight loss, or equal or below about 10%
weight loss.
24. Use according to claim 16, wherein the dynamic viscosity
determined at -35.degree. C. according to ASTM4684 is at least
about 100 mPa*s lower compared to a formulation wherein the
synthetic ester has been replaced by a lubricant base oil selected
from Group I, Group II, Group III base oils or mixtures
thereof.
25. A lubricating composition comprising (i) at least one base oil
selected from a Group I oil according to the API classification,
(ii) a synthetic ester having an Iodine value lower than 10 g I/100
g measured according to DGF C-V 11b, and (iii) optional further
additives.
26. A lubricating composition comprising (i) at least one base oil
selected from a Group I, Group II oil according to the API
classification, or a mixture thereof (ii) a synthetic ester having
an Iodine value lower than 10 g I/100 g measured according to DGF
C-V 11b, (iii) optional further additives.
27. The lubricating composition according to claim 25, wherein the
synthetic ester is a diester of a dicarboxylic acid, and wherein
preferably the diester of the dicarboxylic acid is selected from
the group consisting of di-(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) or mixtures thereof, and preferably is
di-(isopropylheptyl)-adipate (DPHA).
28. A method for reducing deposit formation in a lubricating
composition comprising a base oil comprising at least one Group I,
Group II, or Group III base oil or mixtures thereof, comprising
adding a synthetic ester having an Iodine value lower than 10 g
I/100 g measured according to DGF C-V 11b to said lubricating
composition.
29. The method according to claim 28, wherein the synthetic ester
is added after the lubricating base oil is present in the
equipment.
30. The method according to claim 28, wherein the synthetic ester
is a diester of a dicarboxylic acid, and wherein preferably the
diester of the dicarboxylic acid is selected from the group
consisting of di-(isopropylheptyl)-adipate (DPHA), di-isodecyl
adipate (DIDA), diisotridecyl adipate (DITA), diisononyladipate
(DNA) or mixtures thereof, and preferably is
di(isopropylheptyl)-adipate (DPHA).
Description
[0001] The present invention relates to the field of lubricants. In
particular, the present invention is directed to the use of
lubricant compositions comprising a synthetic ester having an
Iodine value lower than 10 g I/100 g measured according to DGF C-V
11b for the reduction of deposit formation. Further, the present
invention is directed to lubricant compositions comprising a
lubricating base oil and a synthetic ester having an Iodine value
lower than 10 g I/100 g measured according to DGF C-V 11b.
TECHNICAL BACKGROUND
[0002] Commercially available lubricant compositions are based on a
multitude of different natural or synthetic components. The
resulting properties of the various existing lubricant compositions
are tailored to the specific technical requirements by the addition
of further components and selected combinations thereof. In this
way, lubricant compositions are obtained which can fulfill the
complex requirements associated with the various special technical
applications and equipment such as in the field of motor vehicles,
automotive engines and other machinery.
[0003] Typically, lubricant compositions are needed that provide
good cleanliness (i.e. low amounts of deposits), high shear
stability, improved low-temperature viscosity, minimum degree of
evaporation loss, good fuel efficiency, acceptable seal
compatibility and excellent wear protection, among others.
[0004] In particular, lubricant compositions which are continuously
exposed to temperatures of 80.degree. C. or higher tend to form
deposits such as sludge. The deposits may be caused by ageing of
the components of the lubricant composition. Typically, detergents
and dispersants are used to keep the ageing products in solution
and thus either reduce or delay the formation of deposits in the
lubricant composition. These additives, such as the detergents and
dispersants, can only be applied to the composition in certain
amounts since on the one hand they exhibit a limited solubility in
typical lubricant base stocks such as Group I, Group II, Group III
mineral oils or poly-alpha-olefins (PAOs) and on the other hand
show in certain concentrations antagonistic effects with other
additives or negative effects with respect to certain properties
such as low temperature viscosity.
[0005] There is a continued need for lubricant compositions which
are able to provide improved performance characteristics not found
in the already existing ones.
[0006] One particular objective of the present invention is to
provide improved lubricant compositions which exhibit lower
tendencies to form deposits such as sludge. A further objective is
to provide improved lubricant compositions which exhibit lower
tendencies to form deposits measured according to the TEOST MHT
D7097 test and their use in reduction of deposits. A further
objective is to provide improved lubricant compositions which
exhibit lower tendencies to form deposits measured according to
ASTM D4310 and their use in reduction of deposits. One further
objective is to provide improved lubricant compositions which
reduce the deposit formation (and thus improve the cleanliness)
without altering the amount of detergents and dispersants applied
in the composition. It is a further objective to provide a method
for reducing the deposit formation in lubricant compositions.
DESCRIPTION OF THE INVENTION
[0007] The present invention is directed to the use of a
lubricating composition for reducing the formation of deposits,
wherein the composition comprises [0008] (i) at least one
lubricating base oil, and [0009] (ii) at least one synthetic ester
having an Iodine value lower than 10 g I/100 g measured according
to DGF C-V 11b.
[0010] In one embodiment, the synthetic ester having an Iodine
value lower than 10 g I/100 g measured according to DGF C-V 11 b is
selected from (a) a diester of a dicarboxylic acid, (b) a polyol
ester, or (c) mixtures thereof.
[0011] In another embodiment, the dicarboxylic acid moiety of the
diester of the dicarboxylic acid is selected from the group
consisting of phthalic acid, succinic acid, alkyl succinic acids
and alkenyl succinic acids, maleic acid, azelaic acid, suberic
acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer,
malonic acid, alkyl malonic acids, alkenyl malonic acids, glutaric
acid, diglycolic acid, 1,4-cyclohexanedicarboxylic acid,
2,6-decahydronaphthalenedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid
and mixtures thereof.
[0012] In a preferred embodiment, the dicarboxylic acid moiety of
the diester of the dicarboxylic acid is an aliphatic dicarboxylic
acid and is preferably selected from the group consisting of
succinic acid, alkyl succinic acids and alkenyl succinic acids,
maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric
acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic
acids, alkenyl malonic acids, glutaric acid,
1,4-cyclohexanedicarboxylic acid,
2,6-decahydronaphthalenedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid
and mixtures thereof, and more preferably is adipic acid.
[0013] In another preferred embodiment, the ester moiety of the
diester of the dicarboxylic acid is independently selected from the
structure of formula (I)
##STR00001##
[0014] whereas q, r and s are defined as follows,
[0015] q+r=4 to 9,
[0016] s=0 to 5,
[0017] q=1 to 8, and
[0018] r=1 to 6.
[0019] In another preferred embodiment, the the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is selected from the
group consisting of succinic acid, maleic acid, fumaric acid,
adipic acid, malonic acid, and mixtures thereof, and the ester
moiety of the diester of the dicarboxylic acid is independently
selected from the structure of formula (I) above.
[0020] In another preferred embodiment, the the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is adipic acid, and
the ester moiety of the diester of the dicarboxylic acid is
independently selected from the structure of formula (I) above.
More preferred selections of the parameters q, r, and s of this
embodiment are listed in the table below:
TABLE-US-00001 Ester moiety Ethylhexyl q + r = 4 s = 1 q = 1 r = 3
q = 2 r = 2 q = 3 r = 1 Methyloctyl q + r = 6 s = 0 q = 1 r = 5 q =
2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5 r = 1 Propylheptyl q + r = 5
s = 2 q = 1 r = 4 q = 2 r = 3 q = 3 r = 2 q = 4 r = 1 Butyloctyl q
+ r = 6 s = 3 q = 1 r = 5 q = 2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5
r = 1
[0021] In another preferred embodiment, the diester of the
dicarboxylic acid is selected form the group consisting of
di-(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof.
[0022] In another preferred embodiment, the diester of the
dicarboxylic acid is selected form the group consisting of
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof. DPHA is preferred.
[0023] In one embodiment, the amount of diester of the dicarboxylic
acid is from about 5 wt.-% to about 50 wt.-%, from about 5 wt.-% to
about 40 wt.-%, from about 5 wt.-% to about 30 wt.-%, from about 8
wt.-% to about 28 wt.-%, from about 9 wt.-% to about 25 wt.-%, or
from about 17 wt.-% to about 25 wt.-% based on the total weight of
the composition.
[0024] In one embodiment, the synthetic ester having an Iodine
value lower than 10 g I/100 g measured according to DGF C-V 11 b is
a polyol ester. The polyol esters are obtainable by reaction
polyols with carboxylic acids. Preferably the polyols have 2 to 10
hydroxyl groups per molecule and 3 to 30 carbon atoms, optionally
the polyols have one or more ether linkages therein (e.g.
dipentaerythritol). The polyols include but are not limited to
neopentyl glycol (NPG), trimethylol propane (TMP), pentaerythritol
(PE), dipentaerythritol and higher polyether oligomers of
pentaerythritol. The carboxylic acid is preferably selected from a
C.sub.6-C.sub.24 carboxylic acids. In one embodiment, the polyol
ester of the present invention is trimethylolpropane caprylate
(TMTC).
[0025] The lubricant compositions according to the present
invention further comprise a lubricating base oils (or base stock)
selected from the group consisting of mineral oils (Group I, II or
III oils), polyalphaolefins (Group IV oils), polymerized and
interpolymerized olefins, alkyl naphthalenes, alkylene oxide
polymers, silicone oils, phosphate esters and carboxylic acid
esters (Group V oils).
[0026] Preferably, the lubricant base oil is selected from Group I,
Group II, Group III base oils according to the definition of the
API, or mixtures thereof. Group I and Group II base oils are more
preferred.
[0027] Definitions for the base oils (base stocks) according to the
present invention are the same as those found in the American
Petroleum Institute (API) publication "Engine Oil Licensing and
Certification System", Industry Services Department, Fourteenth
Edition, December 1996, Addendum 1, December 1998. Said publication
categorizes base stocks as follows: [0028] a) Group I base oils
contain less than 90 percent saturates and/or greater than 0.03
percent sulfur and have a viscosity index greater than or equal to
80 and less than 120 using the test methods specified in the
following table. [0029] b) Group II base oils contain greater than
or equal to 90 percent saturates and less than or equal to 0.03
percent sulfur and have a viscosity index greater than or equal to
80 and less than 120 using the test methods specified in the
following table. [0030] c) Group III base oils contain greater than
or equal to 90 percent saturates and less than or equal to 0.03
percent sulfur and have a viscosity index greater than or equal to
120 using the test methods specified in the following table
[0031] Analytical Methods for Base Stock:
TABLE-US-00002 Property Test Method Saturates ASTM D 2007 Viscosity
Index ASTM D 2270 Sulfur ASTM D 2622 ASTM D 4294 ASTM D 4927 ASTM D
3120
[0032] d) Group IV base oils contain polyalphaolefins. Synthetic
lower viscosity fluids suitable for the present invention include
the polyalphaolefins (PAOs) and the synthetic oils from the
hydro-cracking or hydro-isomerization of Fischer Tropsch high
boiling fractions including waxes. These are both base oils
comprised of saturates with low impurity levels consistent with
their synthetic origin. The hydro-isomerized Fischer Tropsch waxes
are highly suitable base oils, comprising saturated components of
iso-paraffinic character (resulting from the isomerization of the
predominantly n-paraffins of the Fischer Tropsch waxes) which give
a good blend of high viscosity index and low pour point. Processes
for the hydro-isomerization of Fischer Tropsch waxes are described
in U.S. Pat. Nos. 5,362,378; 5,565,086; 5,246,566 and 5,135,638, as
well in EP 710710, EP 321302 and EP 321304. [0033] Polyalphaolefins
suitable for the lubricant compositions according to the present
invention, include known PAO materials which typically comprise
relatively low molecular weight hydrogenated polymers or oligomers
of alphaolefins which include but are not limited to C.sub.2 to
about C.sub.32 alphaolefins with the C.sub.8 to about Cis
alphaolefins, such as 1-octene, 1-decene, 1-dodecene and the like
being preferred. The preferred polyalphaolefins are poly-1-octene,
poly-1-decene, and poly-1-dodecene, although the dimers of higher
olefins in the range of C.sub.14 to C.sub.18 provide low viscosity
base stocks. [0034] Terms like PAO 4, PAO 6 or PAO 8 are commonly
used specifications for different classes of polyalphaolefins
characterized by their respective viscosity. For instance, PAO 6
refers to the class of polyalphaolefins which typically has
viscosity in the range of 6 mm.sup.2/s at 100.degree. C. A variety
of commercially available compositions are available for these
specifications. [0035] Low viscosity PAO fluids suitable for the
lubricant compositions according to the present invention, may be
conveniently made by the polymerization of an alphaolefin in the
presence of a polymerization catalyst such as the Friedel-Crafts
catalysts including, for example, aluminum trichloride, boron
trifluoride or complexes of boron trifluoride with water, alcohols
such as ethanol, propanol or butanol, carboxylic acids or esters
such as ethyl acetate or ethyl propionate. For example, the methods
disclosed by U.S. Pat. No. 4,149,178 or 3,382,291 may be
conveniently used herein. Other descriptions of PAO synthesis are
found in the following U.S. Pat. No. 3,742,082 (Brennan); U.S. Pat.
No. 3,769,363 (Brennan); U.S. Pat. No. 3,876,720 (Heilman); U.S.
Pat. No. 4,239,930 (Allphin); U.S. Pat. No. 4,367,352 (Watts); U.S.
Pat. No. 4,413,156 (Watts); U.S. Pat. No. 4,434,408 (Larkin); U.S.
Pat. No. 4,910,355 (Shubkin); U.S. Pat. No. 4,956,122 (Watts); and
U.S. Pat. No. 5,068,487 (Theriot). [0036] e) Group V base oils
contain any base stocks not described by Groups I to IV. Examples
of Group V base oils include alkyl naphthalenes, alkylene oxide
polymers, silicone oils, and phosphate esters. [0037] Synthetic
base oils include hydrocarbon oils and halo-substituted hydrocarbon
oils such as polymerized and interpolymerized olefins (e.g.,
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); polyphenyls (e.g.,
biphenyls, terphenyls, alkylated polyphenols); and alkylated
diphenyl ethers and alkylated diphenyl sulfides and derivative,
analogs and homologs thereof. [0038] Alkylene oxide polymers and
interpolymers and derivatives thereof where the terminal hydroxyl
groups have been modified by esterification, etherification, etc.,
constitute another class of known synthetic base oils. These are
exemplified by polyoxyalkylene polymers prepared by polymerization
of ethylene oxide or propylene oxide, and the alkyl and aryl ethers
of polyoxyalkylene polymers (e.g., methyl-polyiso-propylene glycol
ether having a molecular weight of 1000 or diphenyl ether of
polyethylene glycol having a molecular weight of 1000 to 1500); and
mono- and polycarboxylic esters thereof, for example, the acetic
acid esters, mixed C.sub.3-C.sub.8 fatty acid esters and C.sub.13
oxo acid diester of tetraethylene glycol. [0039] Silicon-based oils
such as the polyalkyl-, polyaryl-, polyalkoxy- or
polyaryloxysilicone oils and silicate oils comprise another useful
class of synthetic base oils; such base oils include tetraethyl
silicate, tetraisopropyl silicate, tetra-(2-ethylhexyl)silicate,
tetra-(4-methyl-2-ethylhexyl)silicate, tetra-(p-tert-butyl-phenyl)
silicate, hexa-(4-methyl-2-ethylhexyl)disiloxane,
oly(methyl)siloxanes and poly(methylphenyl)siloxanes. Other
synthetic base oils include liquid esters of phosphorous-containing
acids (e.g., tricresyl phosphate, trioctyl phosphate, diethyl ester
of decylphosphonic acid) and polymeric tetrahydrofurans.
[0040] The lubricant compositions according to the present
invention may also comprise a further additive component.
[0041] The further additive component as used in the present
invention may include an additive package and/or performance
additives.
[0042] The additive package that may be used in the present
invention as well as the compounds relating to performance
additives are considered mixtures of additives that are typically
used in lubricant compositions in limited amounts for mechanically,
physically or chemically stabilizing the lubricant compositions
while special performance characteristics can be further
established or improved by the individual or combined presence of
such selected additives.
[0043] Besides the additive package described in the experimental
part of the present application, a variety of such additive
packages are known to the person skilled in the art and may
commercially be available and typically used in lubricant
compositions. One such preferred additive package that is
commercially available is marketed under the name
Irgalube2030A.RTM. by BASF SE.
[0044] However, the individual components contained in the additive
packages and/or the compounds further defined in the present
invention as so-called performance additives include a larger
number of different types of additives including dispersants, metal
deactivators, detergents, extreme pressure agents (typically boron-
and/or sulfur- and/or phosphorus-containing), anti-wear agents,
antioxidants (such as hindered phenols, aminic antioxidants or
molybdenum compounds), corrosion inhibitors, anti-foam agents,
demulsifiers, pour point depressants, friction modifiers and
mixtures thereof.
[0045] The lubricating composition of the present invention may
further comprise one or more additives selected from the group
consisting of viscosity index improvers, polymeric thickeners,
antioxidants, corrosion inhibitors, detergents, dispersants,
anti-foam agents, dyes, wear protection additives, extreme pressure
additives (EP additives), anti-wear additives (AW additives),
friction modifiers, metal deactivators, pour point depressants and
the like.
[0046] Viscosity Index Improvers:
[0047] In one embodiment, the lubricant composition according to
the present invention may further include at least one viscosity
index improver (VII or VI improver). The viscosity index improvers
include high molecular weight polymers that increase the relative
viscosity of an oil at high temperatures more than they do at low
temperatures. Viscosity index improvers include polyacrylates,
polymethacrylates, alkylmethacrylates,
vinylpyrrolidone/methacrylate copolymers, poly vinylpyrrolidones,
polybutenes, olefin copolymers such as an ethylene-propylene
copolymer or a styrene-butadiene copolymer or polyalkene such as
PIB, styrene/acrylate copolymers and polyethers, and combinations
thereof. The most common VI improvers are methacrylate polymers and
copolymers, acrylate polymers, olefin polymers and copolymers, and
styrenebutadiene copolymers. Other examples of the viscosity index
improver include polymethacrylate, polyisobutylene, alpha-olefin
polymers, alpha-olefin copolymers (e.g., an ethylenepropylene
copolymer), polyalkylstyrene, phenol condensates, naphthalene
condensates, a styrenebutadiene copolymer and the like. Of these,
polymethacrylate having a number average molecular weight of 10000
to 300000, and alpha-olefin polymers or alpha-olefin copolymers
having a number average molecular weight of 1000 to 30000,
particularly ethylene-alpha-olefin copolymers having a number
average molecular weight of 1000 to 10000 are preferred.
[0048] The viscosity index increasing agents can be added and used
individually or in the form of mixtures, conveniently in an amount
within the range of from 0.05 to 20.0% by weight, in relation to
the weight of the base stock.
[0049] (Polymeric) Thickeners:
[0050] In one embodiment, the lubricant composition according to
the present invention may further include at least one (polymeric)
thickener. Suitable (polymeric) thickeners include, but are not
limited to, polyisobutenes (PIB), oligomeric co-polymers (OCPs),
polymethacrylates (PMAs), copolymers of styrene and butadiene, or
high viscosity esters (complex esters).
[0051] Antioxidants:
[0052] In one embodiment, the lubricant composition according to
the present invention may further include at least one antioxidant.
Antioxidants retard the oxidative degradation of base stocks during
service. Such degradation may result in deposits on metal surfaces,
such as the presence of sludge, or a viscosity increase in the
lubricant. One skilled in the art knows a wide variety of oxidation
inhibitors that are useful in lubricating oil compositions.
[0053] Antioxidants include phenolic antioxidants such as hindered
phenolic antioxidants or non-phenolic oxidation inhibitors.
[0054] Useful phenolic antioxidants include hindered phenols. These
phenolic antioxidants may be ashless (metal-free) phenolic
compounds or neutral or basic metal salts of certain phenolic
compounds. Typical phenolic antioxidant compounds are the hindered
phenolics which are the ones which contain a sterically hindered
hydroxyl group, and these include those derivatives of dihydroxy
aryl compounds in which the hydroxyl groups are in the o- or
p-position to each other. Typical phenolic antioxidants include the
hindered phenols substituted with alkyl groups having 6 carbon
atoms or more and the alkylene coupled derivatives of these
hindered phenols. Examples of phenolic materials of this type
2-t-butyl-4-heptyl phenol; 2-t-butyl-4-octyl phenol;
2-t-butyl-4-dodecyl phenol; 2,6-di-t-butyl-4-heptyl phenol;
2,6-di-t-butyl-4-dodecyl phenol; 2-methyl-6-t-butyl-4-heptyl
phenol; and 2-methyl-6-t-butyl-4-dodecyl phenol. Other useful
hindered mono-phenolic antioxidants may include for example
hindered 2,6-di-alkyl-phenolic propionic ester derivatives.
Bis-phenolic antioxidants may also be used in combination with the
present invention. Examples of ortho-coupled phenols include:
2,2'-bis(4-heptyl-6-t-butyl-phenol);
2,2'-bis(4-octyl-6-t-butyl-phenol); and
2,2'-bis(4-dodecyl-6-t-butyl-phenol). Paracoupled bisphenols
include for example 4,4'-bis(2,6-di-t-butyl phenol) and
4,4'-methylenebis(2,6-di-t-butyl phenol).
[0055] Non-phenolic oxidation inhibitors which may be used include
aromatic amine antioxidants and these may be used either as such or
in combination with phenolics. Typical examples of non-phenolic
antioxidants include: alkylated and non-alkylated aromatic amines
such as aromatic monoamines of the formula R.sup.8R.sup.9R.sup.10N,
where R.sup.8 is an aliphatic, aromatic or substituted aromatic
group, R.sup.9 is an aromatic or a substituted aromatic group, and
R.sup.10 is H, alkyl, aryl or R.sup.11S(O).sub.xR.sup.12, where
R.sup.11 is an alkylene, alkenylene, or aralkylene group, R.sup.12
is a higher alkyl group, or an alkenyl, aryl, or alkaryl group, and
x is 0, 1 or 2. The aliphatic group R.sup.8 may contain from 1 to
about 20 carbon atoms, and preferably contains from about 6 to 12
carbon atoms. The aliphatic group is a saturated aliphatic group.
Preferably, both R.sup.8 and R.sup.9 are aromatic or substituted
aromatic groups, and the aromatic group may be a fused ring
aromatic group such as naphthyl. Aromatic groups R.sup.8 and
R.sup.9 may be joined together with other groups such as S.
[0056] Typical aromatic amines antioxidants have alkyl substituent
groups of at least about 6 carbon atoms. Examples of aliphatic
groups include hexyl, heptyl, octyl, nonyl, and decyl. Generally,
the aliphatic groups will not contain more than about 14 carbon
atoms. The general types of amine antioxidants useful in the
present compositions include diphenylamines, phenyl naphthylamines,
phenothiazines, imidodibenzyls and diphenyl phenylene diamines.
Mixtures of two or more aromatic amines are also useful. Polymeric
amine antioxidants can also be used. Particular examples of
aromatic amine antioxidants useful in the present invention
include: p,p'-dioctyldiphenylamine;
t-octylphenyl-alpha-naphthylamine; phenyl-alphanaphthylamine; and
poctylphenyl-alpha-naphthylamine. Sulfurized alkyl phenols and
alkali or alkaline earth metal salts thereof also are useful
antioxidants.
[0057] Corrosion Inhibitors:
[0058] In one embodiment, the lubricant composition according to
the present invention may further include at least one corrosion
inhibitor. Corrosion inhibitors are used to reduce the degradation
of metallic parts that are in contact with the lubricant
composition. Corrosion inhibitors can be described as any materials
(additives, functionalized fluids, etc.) that may form a protective
film on a surface that prevents corrosion agents from reacting or
attacking that surface with a resulting loss of surface material.
Protective films may be absorbed on the surface or chemically
bonded to the surface. Protective films may be constituted from
mono-molecular species, oligomeric species, polymeric species, or
mixtures thereof. Protective films may derive from the intact
corrosion inhibitors, from their combination products, or their
degradation products, or mixtures thereof. Surfaces that may
benefit from the action of corrosion inhibitors may include metals
and their alloys (both ferrous and non-ferrous types) and
non-metals.
[0059] Corrosion inhibitors may include various oxygen-, nitrogen-,
sulfur-, and phosphorus-containing materials, and may include
metal-containing compounds (salts, organometallics, etc.) and
nonmetal-containing or ashless materials. Corrosion inhibitors may
include, but are not limited to, additive types such as, for
example, hydrocarbyl-, aryl-, alkyl-, arylalkyl-, and
alkylaryl-versions of detergents (neutral, overbased), sulfonates,
phenates, salicylates, alcoholates, carboxylates, salixarates,
phosphites, phosphates, thiophosphates, amines, amine salts, amine
phosphoric acid salts, amine sulfonic acid salts, alkoxylated
amines, etheramines, polyetheramines, amides, imides, azoles,
diazoles, triazoles, benzotriazoles, benzothiadoles,
mercaptobenzothiazoles, tolyltriazoles (TTZ-type), heterocyclic
amines, heterocyclic sulfides, thiazoles, thiadiazoles,
mercaptothiadiazoles, dimercaptothiadiazoles (DMTD-type),
imidazoles, benzimidazoles, dithiobenzimidazoles, imidazolines,
oxazolines, Mannich reactions products, glycidyl ethers,
anhydrides, carbamates, thiocarbamates, dithiocarbamates,
polyglycols, etc., or mixtures thereof.
[0060] Detergents:
[0061] In one embodiment, the lubricant composition according to
the present invention may further comprise at least one detergent.
Detergents include cleaning agents that adhere to dirt particles,
preventing them from attaching to critical surfaces. Detergents may
also adhere to the metal surface itself to keep it clean and
prevent corrosion from occurring.
[0062] Detergents include calcium alkylsalicylates, calcium
alkylphenates and calcium alkarylsulfonates with alternate metal
ions used such as magnesium, barium, or sodium. Examples of the
cleaning and dispersing agents which can be used include
metal-based detergents such as the neutral and basic alkaline earth
metal sulphonates, alkaline earth metal phenates and alkaline earth
metal salicylates alkenylsuccinimide and alkenylsuccinimide esters
and their borohydrides, phenates, salienius complex detergents and
ashless dispersing agents which have been modified with sulphur
compounds. These agents can be added and used individually or in
the form of mixtures, conveniently in an amount within the range of
from about 0.01 to about 1.0% by weight in relation to the weight
of the base stock; these can also be high total base number (TBN),
low TBN, or mixtures of high/low TBN.
[0063] Dispersants:
[0064] In one embodiment, the lubricant compositions according to
the present invention further comprises at least one dispersant.
Dispersants are lubricant additives that help to prevent sludge,
varnish and other deposits from forming on critical surfaces. The
dispersant may be a succinimide dispersant (for example
N-substituted long chain alkenyl succinimides), a Mannich
dispersant, an ester-containing dispersant, a condensation product
of a fatty hydrocarbyl monocarboxylic acylating agent with an amine
or ammonia, an alkyl amino phenol dispersant, a hydrocarbyl-amine
dispersant, a polyether dispersant or a polyetheramine
dispersant.
[0065] In one embodiment the succinimide dispersant includes a
polyisobutylene-substituted succinimide, wherein the
polyisobutylene from which the dispersant is derived may have a
number average molecular weight of about 400 to about 5000, or of
about 950 to about 1600.
[0066] Succinimide dispersants and their methods of preparation are
more fully described in U.S. Pat. Nos. 4,234,435 and 3,172,892.
Suitable ester-containing dispersants are typically high molecular
weight esters. These materials are described in more detail in U.S.
Pat. No. 3,381,022.
[0067] In one embodiment the dispersant includes a borated
dispersant. Typically the borated dispersant includes a succinimide
dispersant including a polyisobutylene succinimide, wherein the
polyisobutylene from which the dispersant is derived may have a
number average molecular weight of about 400 to about 5000. Borated
dispersants are described in more detail above within the extreme
pressure agent description.
[0068] Anti Foam Agents:
[0069] In one embodiment, the lubricant compositions according to
the present invention further comprises at least one anti-foam
agent. Anti-foam agents may be selected from silicones,
polyacrylates, and the like. The amount of anti-foam agent in the
lubricant compositions described herein may range from about 0.001
wt.-% to about 0.1 wt.-% based on the total weight of the
formulation. As a further example, an anti-foam agent may be
present in an amount from about 0.004 wt.-% to about 0.008
wt.-%.
[0070] Extreme Pressure Additives (EP Additives):
[0071] In one embodiment, the lubricant compositions according to
the present invention further comprises at least one extreme
pressure additive. In one embodiment according to the present
invention, the extreme pressure agent is a sulfur-containing
compound. In one embodiment, the sulfur-containing compound may be
a sulfurised olefin, a polysulfide, or mixtures thereof. Examples
of the sulfurised olefin include a sulfurised olefin derived from
propylene, isobutylene, pentene; an organic sulfide and/or
polysulfide including benzyldisulfide; bis-(chlorobenzyl)
disulfide; dibutyl tetrasulfide; di-tertiary butyl polysulfide; and
sulfurised methyl ester of oleic acid, a sulfurised alkylphenol, a
sulfurised dipentene, a sulfurised terpene, a sulfurised
Diels-Alder adduct, an alkyl sulphenyl N'N-dialkyl
dithiocarbamates; or mixtures thereof.
[0072] In one embodiment the sulfurised olefin includes a
sulfurised olefin derived from propylene, isobutylene, pentene or
mixtures thereof.
[0073] In one embodiment according to the present invention, the
extreme pressure additive sulfur-containing compound includes a
dimercaptothiadiazole or derivative, or mixtures thereof. Examples
of the dimercaptothiadiazole include compounds such as
2,5-dimercapto-1,3,4-thiadiazole or a hydrocarbyl-substituted
2,5-dimercapto-1,3,4-thiadiazole, or oligomers thereof. The
oligomers of hydrocarbyl-substituted
2,5-dimercapto-1,3,4-thiadiazole typically form by forming a
sulfur-sulfur bond between 2,5-dimercapto-1,3,4-thiadiazole units
to form derivatives or oligomers of two or more of said thiadiazole
units. Suitable 2,5-dimercapto-1,3,4-thiadiazole derived compounds
include for example 2,5-bis(tert-nonyldithio)-1,3,4-thiadiazole or
2-tert-nonyldithio-5-mercapto-1,3,4-thiadiazole. The number of
carbon atoms on the hydrocarbyl substituents of the
hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazole typically
include 1 to 30, or 2 to 20, or 3 to 16.
[0074] Extreme pressure additives include compounds containing
boron and/or sulfur and/or phosphorus. The extreme pressure agent
may be present in the lubricant compositions at 0 wt.-% to about 20
wt.-%, or at about 0.05 wt.-% to about 10.0 wt.-%, or at about 0.1
wt.-% to about 8 wt.-% of the lubricant composition.
[0075] Anti-Wear Additives (AW Additives):
[0076] In one embodiment, the lubricant compositions according to
the present invention further comprises at least one anti-wear
additive. Examples of anti-wear additives include organo borates,
organo phosphites such as didodecyl phosphite, organic
sulfur-containing compounds such as sulfurized sperm oil or
sulfurized terpenes, zinc dialkyl dithiophosphates, zinc diaryl
dithiophosphates, phosphosulfurized hydrocarbons and any
combinations thereof.
[0077] Friction Modifiers:
[0078] In another embodiment, the lubricant compositions according
to the present invention includes at least one friction modifier. A
friction modifier is any material or materials that can alter the
coefficient of friction of a surface lubricated by any lubricant or
fluid containing such material(s). Friction modifiers, also known
as friction reducers, or lubricity agents or oiliness agents, and
other such agents that change the ability of base oils, formulated
lubricant compositions, or functional fluids, to modify the
coefficient of friction of a lubricated surface may be effectively
used in combination with the base oils or lubricant compositions of
the present invention if desired. Friction modifiers may include
metal-containing compounds or materials as well as ashless
compounds or materials, or mixtures thereof. Metal-containing
friction modifiers include metal salts or metal-ligand complexes
where the metals may include alkali, alkaline earth, or transition
group metals. Such metal-containing friction modifiers may also
have low-ash characteristics. Transition metals may include Mo, Sb,
Sn, Fe, Cu, Zn, and others. Ligands may include hydrocarbyl
derivative of alcohols, polyols, glycerols, partial ester
glycerols, thiols, carboxylates, carbamates, thiocarbamates,
dithiocarbamates, phosphates, thiophosphates, dithiophosphates,
amides, imides, amines, thiazoles, thiadiazoles, dithiazoles,
diazoles, triazoles, and other polar molecular functional groups
containing effective amounts of O, N, S, or P, individually or in
combination. In particular, Mo-containing compounds can be
particularly effective such as for example Mo-dithiocarbamates,
Mo(DTC), Mo-dithiophosphates, Mo(DTP), Mo-amines, Mo (Am),
Mo-alcoholates, Mo-alcohol-amides, and the like.
[0079] Ashless friction modifiers may also include lubricant
materials that contain effective amounts of polar groups, for
example, hydroxyl-containing hydrocarbyl base oils, glycerides,
partial glycerides, glyceride derivatives, and the like. Polar
groups in friction modifiers may include hydrocarbyl groups
containing effective amounts of O, N, S, or P, individually or in
combination.
[0080] Other friction modifiers that may be particularly effective
include, for example, salts (both ashcontaining and ashless
derivatives) of fatty acids, fatty alcohols, fatty amides, fatty
esters, hydroxyl-containing carboxylates, and comparable synthetic
long-chain hydrocarbyl acids, alcohols, amides, esters, hydroxy
carboxylates, and the like. In some instances fatty organic acids,
fatty amines, and sulfurized fatty acids may be used as suitable
friction modifiers.
[0081] Examples of friction modifiers include fatty acid esters and
amides, organo molybdenum compounds, molybdenum
dialkylthiocarbamates and molybdenum dialkyl dithiophosphates.
[0082] Metal Deactivators:
[0083] In another embodiment, the lubricant compositions according
to the present invention further comprises at least one metal
deactivator. In various embodiments, one or more metal deactivators
can be included in the composition. Suitable, non-limiting examples
of the one or more metal deactivators include benzotriazoles and
derivatives thereof, for example 4- or 5-alkylbenzotriazoles (e.g.
triazole) and derivatives thereof, 4,5,6,7-tetrahydrobenzotriazole
and 5,5'-methylenebisbenzotriazole; Mannich bases of benzotriazole
or triazole, e.g. 1-[bis(2-ethylhexyl) aminomethyl) triazole and
1-[bis(2-ethylhexyl) am inomethyl)benzotriazole; and
alkoxyalkylbenzotriazoles such as 1-(nonyloxymethyl)benzotriazole,
1-(1-butoxyethyl)benzotriazole and 1-(1-cyclohexyloxybutyl)
triazole, and combinations thereof.
[0084] Additional non-limiting examples of the one or more metal
deactivators include 1,2,4-triazoles and derivatives thereof, for
example 3-alkyl(or aryl)-1, 2,4-triazoles, and Mannich bases of
1,2,4-triazoles, such as 1-[bis(2-ethylhexyl) aminomethy1-1,
2,4-triazole; alkoxyalky1-1, 2,4-triazoles such as
1-(1-butoxyethyl)-1, 2,4-triazole; and acylated 3-amino-1,
2,4-triazoles, imidazole derivatives, for example
4,4'-methylenebis(2-undecyl-5-methylimidazole) and bis[(Nmethyl)
imidazol-2-yl]carbinol octyl ether, and combinations thereof.
[0085] Further non-limiting examples of the one or more metal
deactivators include sulfur-containing heterocyclic compounds, for
example 2-mercaptobenzothiazole, 2,5-dimercapto-1, 3,4-thiadiazole
and derivatives thereof; and 3,5-bis[di(2-ethylhexyl)
aminomethyl]-1, 3,4-thiadiazolin-2-one, and combinations thereof.
Even further non-limiting examples of the one or more metal
deactivators include amino compounds, for example
salicylidenepropylenediamine, salicylaminoguanidine and salts
thereof, and combinations thereof.
[0086] The one or more metal deactivators are not particularly
limited in amount in the composition but are typically present in
an amount of from about 0.01 to about 0.1, from about 0.05 to about
0.01, or from about 0.07 to about 0.1, wt.-% based on the weight of
the composition. Alternatively, the one or more metal deactivators
may be present in amounts of less than about 0.1, of less than
about 0.7, or less than about 0.5, wt.-% based on the weight of the
composition.
[0087] Pour Point Depressants:
[0088] In another embodiment, the lubricant compositions according
to the present invention further comprises at least one pour point
depressant. Pour point depressants (PPD) include polymethacrylates,
alkylated naphthalene derivatives, and combinations thereof.
Commonly used additives such as alkylaromatic polymers and
polymethacrylates are also useful for this purpose. Typically the
treat rates range from about 0.001 wt.-% to about 1.0 wt.-%, in
relation to the weight of the base stock.
[0089] Demulsifiers:
[0090] In another embodiment, the lubricant compositions according
to the present invention further comprises at least one
demulsifier. Demulsifiers include trialkyl phosphates, and various
polymers and copolymers of ethylene glycol, ethylene oxide,
propylene oxide, or mixtures thereof.
[0091] It has been found that the application of the synthetic
ester having an Iodine value of lower than 10 g I/100 g measured
according to DGF c-V 11 b in the lubricating composition according
to the present invention may be used to reduce deposit formation
(i.e. to improve the cleanliness in operation) and the oxidative
stability of lubricating formulations in operation such as motorand
turbine oils. The method DGF c-V 11 b corresponds to the method
according to Kaufmann.
[0092] In one embodiment the reduction of deposits is determined
according to the TEOST MHT D7097 test. The TEOST MHT D7097 test is
designed to predict the deposit forming tendencies of a lubricating
composition in the piston ring belt and upper piston crown area.
Such deposits formed in the ring belt area can cause problems with
equipment operation and longevity. In the TEOST MHT D7097 test
deposit are measured on the rods and the filter. The sum of these
two deposits at rods and filter is called "total deposits".
[0093] In one embodiment, the total deposits are reduced by at
least about 5 mg, by at least about 7 mg, by at least about 10 mg,
by at least about 15 mg measured according to the TEOST MHT D7097
test compared to a composition wherein the synthetic ester has been
replaced by a lubricant base oil selected from Group I, group II,
Group III base oils or mixtures thereof. For illustrative purposes
only, two lubricant composition which may be compared are described
below. The illustrative inventive lubricant composition comprises a
motor oil formulation (e.g. a 5W-20 motor oil formulation according
to SAE classification), to which about 25 wt.-% of a mixture of a
synthetic ester having an Iodine value of lower than 10 g I/100 g
measured according to DGF c-V 11b (such as DPHA) and an additive
package is added. The synthetic ester may be present in an amount
of about 90 wt.-%, the additive package in an amount of about 10
wt.-% of the mixture added. The comparative composition comprises
said motor oil formulation, to which 25 wt.-% of a mixture of e.g.
a Group III mineral oil (replacing the synthetic ester component)
and the same additive package is added. The amount of the Group III
mineral oil and the additive package in the comparative composition
is identical to the ones for the synthetic ester and the additive
package in the inventive composition, respectively.
[0094] In one embodiment, the rod deposits are reduced by at least
about 5 mg, by at least about 7 mg, by at least about 10 mg, by at
least about 15 mg, by at least about 20 mg measured according to
the TEOST MHT D7097 test compared to a composition wherein the
synthetic ester component has been replaced by a lubricant base oil
selected from Group I, group II, Group III base oils or mixtures
thereof.
[0095] In one embodiment, the filter deposits are reduced by at
least about 0.1 mg, by at least about 0.2 mg, or by at least about
0.5 mg measured according to the TEOST MHT D7097 test compared to a
composition wherein the synthetic ester component has been replaced
by a lubricant base oil selected from Group I, Group II, Group III
base oils or mixtures thereof.
[0096] In one embodiment, the total deposits after the TEOST MHT
D7097 test has been reduced by about 10%, by about 15%, by about
20%, by about 25%, by about 30% or by about 40% compared to a
composition wherein the synthetic ester component has been replaced
by a lubricant base oil selected from Group I, group II, Group III
base oils or mixtures thereof.
[0097] In another embodiment, the deposits are measured according
to ASTM D4310. The ASTM method D4310 measures insoluble material or
metal corrosion products (or both) that may form in lubricating
compositions that are subjected to oxidizing conditions.
[0098] In one embodiment, the deposits measured according to ASTM
D4310 are less than about 60 mg, less than about 55 mg, or less
than about 50 mg.
[0099] In one embodiment, the deposits (e.g. sludge) after the test
according to ASTM D4310 has been reduced by about 10%, by about 15%
or by about 20% compared to a composition wherein the synthetic
ester component has been replaced by a lubricant base oil selected
from Group I, Group II, Group III base oils or mixtures
thereof.
[0100] In one embodiment of the present invention, the oxidative
stability of the lubricant composition has been increased compared
to a composition wherein the synthetic ester has been replaced by a
lubricant base oil selected from Group I, Group II, Group III base
oils or mixtures thereof.
[0101] In one embodiment, the oxidation stability is measured by
High Pressure Differential Scanning calorimetry (HPDSC). In one
embodiment, the increase in stability is indicated by a higher
onset temperature at which a sample is oxidized at a certain oxygen
pressure. In an alternative embodiment, the increase in stability
may be indicated by a longer oxidative induction time (OIT) at a
given temperature. Again, the increase in stability is measured in
comparison to a composition wherein the synthetic ester has been
replaced by a lubricant base oil selected from Group I, Group II,
Group III base oils or mixtures thereof, as indicated above. In one
embodiment, the oxidative induction time (OIT) is measured
according to ASTM D6186.
[0102] As mentioned above, lubricant composition, which are
operated at higher temperatures (e.g. at 80.degree. C. or higher)
may show an evaporation loss of the lubricant composition which
loss contributes to a consumption of the lubricating composition
during operation. This may lead to a change in properties of the
lubricating composition. Therefore, it is beneficial that the
evaporation loss of a lubricating composition is decreased or kept
to a minimum. A method to determine the evaporation loss of a
lubricating composition is the so called Noack volatility test. In
one embodiment, the Noack volatility test is performed according to
ASTM D5800 B.
[0103] In one embodiment of the present invention the Noack
volatility measured according to ASTM D5800 (such as procedure B of
ASTM D5800) is decreased compared to a composition wherein the
synthetic ester has been replaced by a lubricant base oil selected
from Group I, Group II, Group III base oils or mixtures
thereof.
[0104] In one embodiment, the Noack volatility is below 12% weight
loss, equal or below about 10% weight loss, equal or below about 9%
weight loss, or equal to or below about 8% weight loss.
[0105] In one embodiment, the Noack volatility of a composition of
the present invention is decreased by about 5%, about 8%, about 10%
or about 12% compared to a composition wherein the synthetic ester
has been replaced by a lubricant base oil selected from Group I,
group II, Group III base oils or mixtures thereof.
[0106] In another embodiment of the present invention the dynamic
viscosity determined at -35.degree. C. according to ASTM4684 is at
least about 100 mPa*s lower, at least about 200 mPa*s lower, at
least about 500 mPa*s lower, at least about 700 mPa*s lower
compared to a formulation wherein the synthetic ester has been
replaced by a lubricant base oil selected from Group I, Group II,
Group III base oil or mixtures thereof. In one embodiment, the
dynamic viscosity is determined after the TEOST MHT D7097 test has
been completed.
[0107] In a preferred embodiment, the lubricating composition
according to the present invention exhibits at least one of the
properties described above, i.e. [0108] (i) reduced deposit
formation measured according to the TEOST MHT D7097 test; [0109]
(ii) reduced deposit formation measured according to ASTM D4310;
[0110] (iii) an improved oxidative stability indicated by a higher
onset temperature in a HPDSC ramping experiment; [0111] (iv) an
improved oxidative stability indicated by a longer oxidation
inductive time in a HPDSC oxidation inductive time experiment;
[0112] (v) a reduced Noack volatility (measured according to ASTM
D5800, e.g. procedure B); [0113] (vi) a lower dynamic viscosity
determined at -35.degree. C. according to ASTM 4684.
[0114] It is apparent to a person skilled in the art that various
combinations (i.e. a composition exhibiting two of the above
properties, three of the above properties, four of the above
properties, etc) of the properties listed above under items (i) to
(vi) are also encompassed in the present invention.
[0115] In another embodiment, the present invention is also
directed to a lubricating composition comprising [0116] (i) a
synthetic ester having an Iodine value lower than 10 g I/100 g
measured according to DGF C-V 11b, and [0117] (ii) optional further
additives.
[0118] In one aspect of this embodiment, the synthetic ester is a
diester of a dicarboxylic acid. In a preferred aspect of this
embodiment, the diester of the dicarboxylic acid is selected from
the group consisting of di-(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) and mixtures thereof.
Di-(isopropylheptyl)adipate (DPHA) is particularly preferred.
[0119] In another embodiment, the present invention is also
directed to a lubricating composition comprising [0120] (i) at
least one base oil selected from a Group I, Group II or Group III
oil according to the API classification or a mixture thereof,
[0121] (ii) a synthetic ester having an Iodine value lower than 10
g I/100 g measured according to DGF C-V 11 b, and [0122] (iii)
optional further additives.
[0123] In another embodiment, the at least one base oil is a Group
I base oil. Thus, the present invention is also directed to a
lubricating composition comprising [0124] (i) at least one base oil
selected from a Group I oil according to the API classification,
(ii) a synthetic ester having an Iodine value lower than 10 g I/100
g measured according to DGF C-V 11 b, and [0125] (iii) optional
further additives.
[0126] In another embodiment of this aspect, wherein the synthetic
ester is a diester of a dicarboxylic acid, the present invention is
also directed to a lubricating composition comprising [0127] (i) at
least one base oil selected from a Group I oil according to the API
classification, [0128] (ii) a diester of a dicarboxylic acid, and
[0129] (iii) optional further additives.
[0130] In a preferred embodiment, the diester of the dicarboxylic
acid of this embodiment is selected from a diester, wherein the
ester moiety of the diester of the dicarboxylic acid is
independently selected from the structure of formula (I)
##STR00002##
[0131] whereas q, r and s are defined as follows,
[0132] q+r=4 to 9,
[0133] s=0 to 5,
[0134] q=1 to 8, and
[0135] r=1 to 6.
[0136] In another preferred embodiment, the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is selected from the
group consisting of succinic acid, maleic acid, fumaric acid,
adipic acid, malonic acid, and mixtures thereof, and the ester
moiety of the diester of the dicarboxylic acid is independently
selected from the structure of formula (I) above.
[0137] In another preferred embodiment, the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is adipic acid, and
the ester moiety of the diester of the dicarboxylic acid is
independently selected from the structure of formula (I) above.
More preferred selections of the parameters q, r, and s of this
embodiment are listed in the table below:
TABLE-US-00003 Ester moiety Ethylhexyl q + r = 4 s = 1 q = 1 r = 3
q = 2 r = 2 q = 3 r = 1 Methyloctyl q + r = 6 s = 0 q = 1 r = 5 q =
2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5 r = 1 Propylheptyl q + r = 5
s = 2 q = 1 r = 4 q = 2 r = 3 q = 3 r = 2 q = 4 r = 1 Butyloctyl q
+ r = 6 s = 3 q = 1 r = 5 q = 2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5
r = 1
[0138] In another embodiment, the diester of the dicarboxylic acid
of the lubricating composition of the present invention is selected
form the group consisting of di-(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) or mixtures thereof. In another embodiment,
the diester of the dicarboxylic acid of the lubricating composition
of the present invention is selected form the group consisting of
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof. Di-(isopropylheptyl)-adipate (DPHA) is
particularly preferred. Di-(isopropylheptyl)-adipate (DPHA) is
commercially available as Synative ES DPHA from BASF SE.
[0139] In a further preferred embodiment, the lubricating
composition comprises [0140] (i) at least one base oil selected
from a Group I oil according to the API classification, [0141] (ii)
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof. and [0142] (iii) optional further additives.
[0143] In a further embodiment, the lubricating composition
comprises [0144] (i) at least one base oil selected from a Group I,
Group II or Group III oil according to the API classification or a
mixture thereof, [0145] (ii) di-(isopropylheptyl)-adipate (DPHA),
diisononyladipate (DNA) or mixtures thereof. and [0146] (iii)
optional further additives.
[0147] In a further preferred embodiment, the lubricating
composition comprises [0148] (ii) at least one base oil selected
from a Group I oil according to the API classification, [0149] (ii)
di-(isopropylheptyl)-adipate (DPHA), and [0150] (iii) optional
further additives.
[0151] In a further embodiment, the lubricating composition
comprises [0152] (ii) at least one base oil selected from a Group
I, Group II or Group III oil according to the API classification or
a mixture thereof, [0153] (ii) di-(isopropylheptyl)-adipate (DPHA),
and [0154] (iii) optional further additives.
[0155] In one embodiment, the further additives comprise
antioxidants, corrosion inhibitors and metal deactivators. Such an
additive package is for example commercially available as Irgalube
2030 A.RTM. from BASF SE.
[0156] In one embodiment the Group I, Group II, Group III base oil
or a mixture thereof may be present in an amount from about 70
wt.-% to about 95 wt.-% based on the total lubricating composition.
The diester of the dicarboxylic acid may be present in an amount
from about 5 wt.-% to about 15 wt. % based on the total lubricating
composition. The further additives, if present, may be present in
an amount from about 0.1 wt.-% to about 10.0 wt.-% based on the
total lubricating composition.
[0157] In one embodiment the Group I, Group II, Group III base oil
or a mixture thereof may be present in an amount from about 70
wt.-% to about 95 wt.-% based on the total lubricating composition.
The diester of the dicarboxylic acid may be present in an amount
from about 5 wt.-% to about 15 wt. % based on the total lubricating
composition. The further additives, if present, may be present in
an amount from about 0.1 wt.-% to about 3.0 wt.-% based on the
total lubricating composition.
[0158] In one embodiment the Group I base oil may be present in an
amount from about 70 wt.-% to about 95 wt.-% based on the total
lubricating composition. The diester of the dicarboxylic acid may
be present in an amount from about 5 wt.-% to about 15 wt. % based
on the total lubricating composition. The further additives, if
present, may be present in an amount from about 0.1 wt.-% to about
3.0 wt.-% based on the total lubricating composition.
[0159] In another embodiment the Group I base oil may be present in
an amount from about 80 wt.-% to about 95 wt.-% based on the total
lubricating composition. The diester of the dicarboxylic acid may
be present in an amount from about 5 wt.-% to about 13 wt.-% based
on the total lubricating composition. The further additives, if
present, may be present in an amount from about 0.1 wt.-% to about
3.0 wt.-% based on the total lubricating composition.
[0160] In another embodiment, the present invention is also
directed to a lubricating composition comprising [0161] (i) at
least one base oil from a Group I or Group II oil according to the
API classification, or a mixture thereof, [0162] (ii) a synthetic
ester having an Iodine value lower than 10 g I/100 g measured
according to DGF C-V 11 b, and [0163] (iii) optional further
additives.
[0164] In another embodiment of this aspect, the synthetic ester is
a diester of a dicarboxylic acid. Thus, the present invention is
also directed to a lubricating composition comprising [0165] (i) at
least one base oil from a Group I, Group II oil according to the
API classification, or a mixture thereof, [0166] (ii) a diester of
a dicarboxylic acid, and [0167] (iii) optional further
additives.
[0168] In another aspect, the present invention is also directed to
a lubricating composition comprising [0169] (i) at least one base
oil from a Group I, Group II oil according to the API
classification, or a mixture thereof, [0170] (ii) a diester of a
dicarboxylic acid, wherein the diester of the dicarboxylic acid is
selected from the group consisting of Di-(isopropylheptyl)-adipate
(DPHA), diisononyladipate (DNA), or mixtures thereof and [0171]
(iii) optional further additives.
[0172] In another aspect, the present invention is also directed to
a lubricating composition comprising [0173] (i) at least one base
oil from a Group I, Group II oil according to the API
classification, or a mixture thereof, [0174] (ii) a diester of a
dicarboxylic acid, wherein the diester of the dicarboxylic acid is
Di(isopropylheptyl)-adipate (DPHA), and [0175] (iii) optional
further additives.
[0176] In one preferred embodiment, the lubricating composition
comprises a motor oil formulation, suchs a a typical 5W-20 motor
oil formulation.
[0177] In a preferred embodiment, the diester of the dicarboxylic
acid on this embodiment is selected from a diester, wherein the
ester moiety of the diester of the dicarboxylic acid is
independently selected from the structure of formula (I)
##STR00003##
[0178] whereas q, r and s are defined as follows,
[0179] q+r=4 to 9,
[0180] s=0 to 5,
[0181] q=1 to 8, and
[0182] r=1 to 6.
[0183] In another preferred embodiment, the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is selected from the
group consisting of succinic acid, maleic acid, fumaric acid,
adipic acid, malonic acid, and mixtures thereof, and the ester
moiety of the diester of the dicarboxylic acid is independently
selected from the structure of formula (I) above.
[0184] In another preferred embodiment, the dicarboxylic acid
moiety of the diester of the dicarboxylic acid is adipic acid, and
the ester moiety of the diester of the dicarboxylic acid is
independently selected from the structure of formula (I) above.
More preferred selections of the parameters q, r, and s of this
embodiment are listed in the table below:
TABLE-US-00004 Ester moiety Ethylhexyl q + r = 4 s = 1 q = 1 r = 3
q = 2 r = 2 q = 3 r = 1 Methyloctyl q + r = 6 s = 0 q = 1 r = 5 q =
2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5 r = 1 Propylheptyl q + r = 5
s = 2 q = 1 r = 4 q = 2 r = 3 q = 3 r = 2 q = 4 r = 1 Butyloctyl q
+ r = 6 s = 3 q = 1 r = 5 q = 2 r = 4 q = 3 r = 3 q = 4 r = 2 q = 5
r = 1
[0185] In another embodiment, the diester of the dicarboxylic acid
of the lubricating composition of the present invention is selected
form the group consisting of di-(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) or mixtures thereof. In another embodiment,
the diester of the dicarboxylic acid of the lubricating composition
of the present invention is selected form the group consisting of
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof. Di-(isopropylheptyl)-adipate (DPHA) is
particularily preferred. Di-Osopropylheptylyadipate (DPHA) is
commercially available as Synative ES DPHA from BASF SE.
[0186] In a further preferred embodiment, the lubricating
composition comprises [0187] (i) at least one base oil selected
from a Group I, Group II oil according to the API classification,
or a mixture thereof, [0188] (ii) di-(isopropylheptyl)-adipate
(DPHA), and [0189] (iii) optional further additives.
[0190] In one embodiment, the further additives may comprise
dispersants, anti-foam agents, diluents, detergents, anti-wear
agents, antioxidants, corrosion inhibitors and metal
deactivators.
[0191] In one embodiment the lubricating composition according to
the present invention may comprise at least one base oil selected
from a Group I, Group II oil according to the API classification,
or a mixture thereof in an amount from about 70 wt.-% to about 95
wt.-% based on the total lubricating composition. The diester of
the dicarboxylic acid may be present in an amount from about 5
wt.-% to about 30 wt. % based on the total lubricating composition.
The further additives, if present, may be present in an amount from
about 0.1 wt.-% to about 20.0 wt.-% based on the total lubricating
composition.
[0192] In one embodiment the lubricating composition according to
the present invention may comprise at least one base oil selected
from a Group I, Group II oil according to the API classification,
or a mixture thereof in an amount from about 75 wt.-% to about 95
wt.-% based on the total lubricating composition. The diester of
the dicarboxylic acid may be present in an amount from about 10
wt.-% to about 25 wt. % based on the total lubricating composition.
The further additives, if present, may be present in an amount from
about 0.1 wt.-% to about 20.0 wt.-% based on the total lubricating
composition.
[0193] In one embodiment the lubricating composition according to
the present invention may comprise at least motor oil in an amount
from about 70 wt.-% to about 95 wt.-% based on the total
lubricating composition, a diester of the dicarboxylic acid in an
amount from about 5 wt.-% to about 30 wt. % based on the total
lubricating composition, and further additives, if present, in an
amount from about 0.1 wt.-% to about 20.0 wt.-% based on the total
lubricating composition.
[0194] In a preferred embodiment of the invention the method for
reducing deposit formation in a lubricating composition comprising
a base oil comprising at least one Group I, Group II or Group III
base oil or mixtures thereof, comprising adding a synthetic ester
having an Iodine value lower than 10 g I/100 g measured according
to DGF C-V 11b to said lubricating composition.
[0195] In a preferred embodiment of the invention the method for
reducing deposit formation in a lubricating base oil comprising at
least one Group I, Group II or Group III base oil or mixtures
thereof, comprising adding a synthetic ester having an Iodine value
lower than 10 g I/100 g measured according to DGF C-V 11b to said
lubricating base oil.
[0196] In one embodiment, the present invention is directed to a
method for reducing deposit formation in a lubricating base oil
comprising Group I, Group II base oils or mixtures thereof,
comprising adding an effective amount of a synthetic ester having
an Iodine value lower than 10 g I/100 g measured according to DGF
C-V 11 b to said lubricating base oil.
[0197] In one embodiment, the synthetic ester is added in an amount
from about 5 wt.-% to about 50 wt.-%, from about 10 wt.-% to about
40 wt.-%, from about 15 wt.-% to about 35 wt.-% based on the amount
of the lubricating base oil.
[0198] In one embodiment, the synthetic ester is added after the
lubricating base oil is present in the equipment to be lubricated.
The equipment can be an engine such as a motor e.g. a vehicle
motor. In one embodiment, the synthetic ester is added to the
lubricating base oil of an engine (such as a motor oil) when or
after the running in phase of said engine is completed. In another
embodiment, the synthetic ester is added to the lubricating base
oil when or after about 10% or about 20% of the control interval
for this engine is reached.
[0199] In another embodiment, the synthetic ester is a diester from
a dicarboxylic acid. Preferabyl the dicarboxylic acid moiety of
said diester is selected from the group consisting of succinic
acid, maleic acid, fumaric acid, adipic acid, malonic acid, and
mixtures thereof, and the ester moiety of the diester of the
dicarboxylic acid is independently selected from the structure of
formula (I) above. In a more preferred embodiment, the dicarboxylic
acid ester is selected from the group consisting of
di-(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof, and preferably is di(isopropylheptyl)-adipate (DPHA).
[0200] In one embodiment, the synthetic ester having an Iodine
value of lower than 10 g I/100 g measured according to DGF C-V 11 b
can be used as an ester base stock for lubricating applications. In
one embodiment the synthetic ester is the major component in the
base stock (i.e. it is present in an amount greater than 50.0 wt.-%
based on the base stock). In one embodiment the synthetic ester is
a minor component of the base stock (i.e. it is present in an
amount less than 50.0 wt.-% based on the base stock).
[0201] In another embodiment the synthetic ester having an Iodine
value of lower than 10 g I/100 g measured according to DGF C-V 11 b
or the lubricating compositions of the present invention are used
in engine oils, such as light, medium and heavy duty engine oils,
industrial engine oils, marine engine oils, automotive engine oils,
crankshaft oils, compressor oils, refrigerator oils, hydrocarbon
compressor oils; very low-temperature lubricating oils and fats;
high temperature lubricating oils and fats; wire rope lubricants;
textile machine oils; refrigerator oils; aviation and aerospace
lubricants; aviation turbine oils; hydraulic oils; transmission
oils; turbine oils; gas turbine oils; spindle oils; spin oils;
traction fluids; transmission oils, such as plastic transmission
oils; passenger car transmission oils, truck transmission oils,
industrial transmission oils; industrial gear oils; axle oils;
insulating oils; instrument oils; brake fluids; transmission
liquids; shock absorber oils; heat distribution medium oils;
transformer oils; fats; chain oils; minimum quantity lubricants for
metalworking operations; oil to the warm and cold working; oil for
water-based metalworking liquids; oil for neat oil metalworking
fluids; oil for semi-synthetic metalworking fluids; oil for
synthetic metalworking fluids; drilling detergents for the soil
exploration; hydraulic oils; in biodegradable lubricants or
lubricating greases or waxes; chain saw oils; release agents;
moulding fluids; gun, pistol and rifle lubricants or watch
lubricants and food grade approved lubricants. Preferably, the
synthetic ester having an Iodine value of lower than 10 g I/100 g
measured according to DGF C-V 11 b or the lubricating compositions
of the present invention are used in engine oils; aviation and
aerospace lubricants; aviation turbine oils; hydraulic oils;
transmission oils, turbine oils, gas turbine oils or axle oils
applications. The method of the present invention leads to reduced
deposits and thus to an improved cleanliness of the equipment such
as engines, turbines, hydraulic circuits, transmissions and
axles.
[0202] As used herein, the term "dicarboxylic acid moiety of the
diester of the dicarboxylic acid" and "ester moiety of the diester
of the dicarboxylic acid" refer to the respective moieties as shown
in the figure below illustrated by the non limiting example of the
dicarboxylic acid moiety of adipic acid and two ester moieties
according to formula (I):
##STR00004##
[0203] As used herein, the terms "base oil" and "base stock" are
used interchangeably.
[0204] The determination of the Iodine value according to DGF C-V
11 b refers to the method described by the "Deutsche
Einheitsmethode zur Untersuchung von Fetten, Fettprodukten,
Tensiden and verwandten Stoffen", 2. Edition 2014. The method DGF
C-V 11 b for the determination of the Iodine value refers to the
cyclohexane/glacial acetic acid method according to Kaufmann.
[0205] As used herein, the term "about" means that the value
following said term may be in the range of .+-.15% of said value,
preferably .+-.10% of said value, even more preferably .+-.5% of
said value.
EXAMPLES
[0206] Methods
[0207] The various viscosities of the lubricant compositions
according to the present invention have been determined following
established industry standards:
[0208] The kinematic viscosity at 100.degree. C. is determined
according to the ASTM D445.
[0209] The yield stress and the low temperature viscosity at
-35.degree. C. is determined according to ASTM D4684.
[0210] HPDSC Measurements:
[0211] For the HPDSC measurements a small quantity of the lubricant
composition sample to be tested is weighted into a sample pan and
placed into the test cell. The test cell is adjusted to the desired
temperature and then pressurized with oxygen to the desired oxygen
pressure.
[0212] HPDSC ramping method: A heating rate of 5.degree. C./min was
used for this method.
[0213] HPDSC OIT method: The OIT was determined at a temperature of
210.degree. C. at oxygen pressures of 155 psi and 200 psi,
respectively.
[0214] Composition of Conventional 5W-20 Formulation (Formulation
1)
[0215] The composition of the 5W-20 formulation applied is shown in
Table 1:
TABLE-US-00005 TABLE 1 Component Component type Amount (wt.-%)
Irgaflo 649p Pour Point Depressant 0.300 Additive package 9.430 EHC
45 (Exxon Mobil) Base oil 67.070 EHC 60 (Exxon Mobil) Base oil
20.000 Infineum V534 Viscosity modifier 3.200
[0216] The components of the 5W-20 formulation have been combined
and blended for 1 hour at 50.degree. C. prior to use.
[0217] Composition of the Additive Package
[0218] The composition of the additive package is shown in Table
2:
TABLE-US-00006 TABLE 2 Component Component type Amount (wt.-%)
Infinuem C9268 Dispersant 35.5673 Antifoam agent Antifoam 0.0530
Diluent* Diluent 11.0604 Infineum C9330 Detergent 18.8982 Infineum
C9417 Anti-wear 10.5610 Irganox L135 Antioxidant 9.0138 Irganox L57
Antioxidant 14.8462
[0219] The additive package is obtained by the following procedure:
To the blend of Infinuem C9268, the anti-foam agent and the
diluent, Infineum C9330 is given and further blended for 1 h at
95.degree. C. Subsequently Infineum C9417 is added and the mixture
is further blended for 1 hour at 70.degree. C. Irganox L135 and
Irganox L57 are added and the resulting mixture is blended for an
additional hour at 60.degree. C.
Example 1: Determination of Deposits According to the TEOST MHT
D7097 Test
[0220] To compare the deposit formation of an inventive composition
and a comparative composition, conventional 5W-20 motor oil
formulations (Formulation 1) have been applied. In the comparative
composition, to the 5W-20 oil formulation a mixture of a Group III
mineral oil and an additive package have been added (resulting in
Formulation 2), while in the inventive formulation (Formulation 3),
a diester of a dicarboxylic acid (DPHA) and an additive package
have been applied. The formulations are listed in Table 3:
TABLE-US-00007 TABLE 3 Formulation 2 Formulation 3 Component
(comparative) (wt.-%) (inventive) (wt.-%) Formulation 1 75.00 75.00
Nexbase 3030 (group 22.64 III base oil) DPHA 22.64 Additive package
2.36 2.36
[0221] The composition of the additive package used in the present
example is provided above.
[0222] The test procedure is described below:
[0223] Test Protocol: Fuel economy testing on the engine
dynamometer was conducted using a 5.7 L GM crate engine with a high
volume oil pan. The engine was run at controlled steady state
conditions simulating highway temperatures, speed and load. Fuel
consumption was measured constantly with a Coriolis type fuel flow
meter. After a specific aging period where oil viscosity and fuel
consumption were stabilized, a measured amount of candidate was
added to the crankcase. Fuel economy percent benefit was calculated
from consumption values before the addition of the additive to the
end of test. At end of test, Rocker Covers, Cam baffles, Oil Pan,
Oil Screen and Front Cover are removed for visual inspection and
photos of deposit formation. [0224] Base Oil--6 quarts
(corresponding to about 5678 ml) of Formulation 1 (5W20 motor oil
formulation) [0225] Candidate--2 quarts (corresponding to about
1893 ml) of a mixture of DPHA and additive package used in
Formulation 3 (together 25 wt.-% DPHA and additive package), or 2
quarts (corresponding to about 1893 ml) mixture of Nexbase 3030 and
additive package used in Formulation 2 (25 wt.-% Nexbase 3030 and
additive package)
[0226] Oil Sampling has been performed as follows: [0227] 28.25
hours--take 20 ml sample for viscosity measurements [0228] 28.50
hours--Add 2 quarts of Candidate [0229] 28.75 hours--(15 minutes
after candidate addition) 1 quart sample [0230] 90.00 hours--End of
Test, take 1 quart sample and save all drain oil
[0231] The following test cycle has been followed: [0232] 1. Run
Highway Cycle (2500 rpm, 35 Nm Torque, 125c oil) for 12 to 16 hours
overnight till fuel consumption is stable. [0233] 2. Run and
measure fuel consumption. [0234] 3. Follow Oil Sampling procedure
above [0235] 4. Continue test to 90 hours with fuel consumption
measurements. [0236] 5. At 90 hours end of test (EOT), take 1 qt.
sample. (save drain oil) [0237] 6. When engine is cool enough to
work on, remove and display RAC's, front cover, cam baffles, oil
pump and oil pan for inspection and photos. Notify test
engineer.
[0238] The results of the various tests of Formulations 1, 2 and 3
are summarized in Table 4 below:
TABLE-US-00008 TABLE 4 Formulation Formulation Formulation
Formulation Formulation Formulation 1 2 2 (end of test) 1 3 3 (end
of test) Kin. viscosity 8.277 6.276 7.472 8.366 6.649 7.004 at
100.degree. C. (mm.sup.2/s) MRV/yield stress (Pa) Y .ltoreq. 35 Y
.ltoreq. 35 Y .ltoreq. 35 Y .ltoreq. 35 Y .ltoreq. 35 Y .ltoreq. 35
MRV*/viscosity 8913 6030 8386 8913 5860 6786 (mPa*s) Noack
volatility** 12 8.7 7.6 7 (wt.-% loss) HPDSC.sup.# ramping
(.degree. C.) 155 psi O.sub.2 246 256.2 200 psi O.sub.2 243.8 n/a
HPDSC.sup.## OIT (min) 155 psi O.sub.2 41.43 84.99 200 psi O.sub.2
37.26 79.65 Deposits*** rod (mg) 30 6.6 Deposits*** filter 2.4 2.3
(mg) Total deposits*** 32.4 8.9 Formulation (mg) *MRV--Mini Rotary
Viscosimeter (measurements at -35.degree. C. according to ASTM
D4684) **The Noack volatility is measured according to ASTM D5800 B
***Deposits are measured according to the TEOST MHT D7097 test. The
total deposits are obtained by summing up rod deposits and filter
deposits. .sup.#High Pressure Differential Scanning Calorimetry
(HPDSC): ramping was performed with 5.degree. C./min. .sup.##HPDSC:
oxidation induction time (OIT) measured at 210.degree. C.
Example 2: Determination of Deposits According to ASTM D4310
[0239] Furthermore, the synthetic ester of the invention was tested
in a turbine oil formulation. To a typical Group I mineral oil
formulation has been added DPHA. With this formulation a turbine
test according to ASTM D4310 has been performed. The composition of
the formulations tested are summarized in Table 5 below:
TABLE-US-00009 TABLE 5 Component Formulation 4 (wt.-%) Formulation
5 (wt.-%) Group I oil* 99.57 89.57 DPHA** 0.0 10.00 Additive
package*** 0.43 0.43 *A mixture of 65% AP/E CORE 150 and 35% AP/E
CORE 600 was used as a Group I mineral oil. AP/E CORE 150 and AP/E
CORE 600 are commercially available from Exxon Mobil. **Synative ES
DPHA from BASF SE ***Irgalube 2030A from BASF SE
[0240] The kinematic viscosity at 100.degree. C. of formulation 4
was 6.82 mm.sup.2/s. The kinematic viscosity at 100.degree. C. of
formulation 5 was 6.25 mm.sup.2/s.
[0241] The sludge determined according to ASTM D4310 was 65.1 mg
for Formulation 4 (comparative) and 46.6 mg for Formulation 5
(inventive).
[0242] Preferred embodiments of the present invention are described
in the following items: [0243] 1. Use of a lubricating composition
for reducing the formation of deposits, wherein the composition
comprises [0244] (i) at least one lubricating base oil, and [0245]
(ii) at least one synthetic ester having an Iodine value lower than
10 g I/100 g measured according to DGF C-V 11b. [0246] 2. Use
according to item 1, wherein the synthetic ester is selected from
[0247] (a) a diester of a dicarboxylic acid, [0248] (b) a polyol
ester, or [0249] (c) mixtures thereof. [0250] 3. Use according to
items 1 or 2, wherein the dicarboxylic acid moiety of the diester
of the dicarboxylic acid is selected from the group consisting of
phthalic acid, succinic acid, alkyl succinic acids and alkenyl
succinic acids, maleic acid, azelaic acid, suberic acid, sebacic
acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid,
alkyl malonic acids, alkenyl malonic acids, glutaric acid,
diglycolic acid, 1,4-cyclohexanedicarboxylic acid,
2,6-decahydronaphthalenedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid
and mixtures thereof. [0251] 4. Use according to any one of the
items 1 to 3, wherein the dicarboxylic acid moiety of the diester
of the dicarboxylic acid is an aliphatic dicarboxylic acid and is
preferably selected from the group consisting of succinic acid,
alkyl succinic acids and alkenyl succinic acids, maleic acid,
azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic
acid, linoleic acid dimer, malonic acid, alkyl malonic acids,
alkenyl malonic acids, glutaric acid, 1,4-cyclohexanedicarboxylic
acid, 2,6-decahydronaphthalenedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid
and mixtures thereof, and more preferably is adipic acid. [0252] 5.
Use according to any one of items 1 to 4, wherein the ester moiety
of the diester of the dicarboxylic acid is independently selected
from the structure of formula (I)
##STR00005##
[0253] whereas q, r and s are defined as follows,
[0254] q+r=4 to 9,
[0255] s=0 to 5,
[0256] q=1 to 8, and
[0257] r=1 to 6. [0258] 6. Use according to any one of the items 1
to 5, wherein the diester of the dicarboxylic acid is selected form
the group consisting of di-(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) or mixtures thereof, and preferably is
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof. [0259] 7. Use according to any one of the items 1
to 6, wherein the amount of diester of the dicarboxylic acid is
from about 5 wt.-% to about 50 wt.-%, from about 5 wt.-% to about
40 wt.-%, from about 5 wt.-% to about 30 wt.-%, from about 8 wt.-%
to about 28 wt.-%, from about 9 wt.-% to about 25 wt.-%, or from
about 17 wt.-% to about 25 wt.-% based on the weight of the
composition. [0260] 8. Use according to any one of items 1 to 7,
wherein the lubricating base oil is selected from Group I, Group
II, Group III base oils according to the definition of the API, or
mixtures thereof, and preferably is selected from Group I, Group II
base oils, or mixtures thereof. [0261] 9. Use according to any one
of items 1 to 8, wherein the composition further comprises one or
more other additives selected from the group consisting of
viscosity index improvers, polymeric thickeners, antioxidants,
corrosion inhibitors, detergents, dispersants, anti-foam agents,
dyes, extreme pressure additives, antiwear additives, friction
modifiers, metal deactivators, pour point depressants and the like.
[0262] 10. Use according to any one of items 1 to 9 wherein the
deposits are determined according to the TEOST MHT D7097 test.
[0263] 11. Use according to any one of items 1 to 10, wherein the
deposits are reduced by at least about 5 mg, by at least about 7
mg, by at least about 10 mg, by at least about 15 mg measured
according to the TEOST MHT D7097 test compared to a composition
wherein the synthetic ester has been replaced by a lubricant base
oil selected from Group I, Group II, Group III base oils or
mixtures thereof. [0264] 12. Use according to any one of items 1 to
9 wherein the deposits are measured according to ASTM D4310. [0265]
13. Use according to any one of items 1 to 9 and 12, wherein the
deposits measured according to ASTM D4310 are less than about 60
mg, less than about 55 mg, or less than about 50 mg. [0266] 14. Use
according to any one of items 1 to 13, wherein the oxidation
stability measured according to HPDSC test is increased compared to
a composition wherein the synthetic ester has been replaced by a
lubricant base oil selected from Group I, Group II, Group III base
oils or mixtures thereof. [0267] 15. Use according to any one of
items 1 to 14, wherein the Noack volatility measured according to
ASTM D5800 is decreased compared to a composition wherein the
synthetic ester has been replaced by a lubricant base oil selected
from Group I, Group II, Group III base oils or mixtures thereof.
[0268] 16. Use according to any one of items 1 to 15, wherein the
Noack volatility is below 12% weight loss, or equal or below about
10% weight loss. [0269] 17. Use according to any one of items 1 to
16, wherein the dynamic viscosity determined at -35.degree. C.
according to ASTM4684 is at least about 100 mPa*s lower compared to
a formulation wherein the synthetic ester has been replaced by a
lubricant base oil selected from Group I, Group II, Group III base
oils or mixtures thereof [0270] 18. A lubricating composition
comprising [0271] (i) at least one base oil selected from a Group I
oil according to the API classification, [0272] (ii) a synthetic
ester having an Iodine value lower than 10 g I/100 g measured
according to DGF C-V 11 b, and [0273] (iii) optional further
additives. [0274] 19. A lubricating composition comprising [0275]
(i) at least one base oil selected from a Group I, Group II oil
according to the API classification, or a mixture thereof [0276]
(ii) a synthetic ester having an Iodine value lower than 10 g I/100
g measured according to DGF C-V 11b, [0277] (iii) optional further
additives. [0278] 20. The lubricating composition according to any
one of items 18 and 19, wherein the synthetic ester is a diester of
a dicarboxylic acid. [0279] 21. The lubricating composition
according to any one of items 18 to 20, wherein the diester of the
dicarboxylic acid is selected from the group consisting of
di-(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof, and preferably is di-(isopropylheptyl)-adipate (DPHA), and
preferably is di(isopropylheptyl)-adipate (DPHA), diisononyladipate
(DNA) or mixtures thereof. [0280] 22. A method for reducing deposit
formation in a lubricating composition comprising a base oil
comprising at least one Group I, Group II, or Group III base oil or
mixtures thereof, comprising adding a synthetic ester having an
Iodine value lower than 10 g I/100 g measured according to DGF C-V
11 b to said lubricating composition. [0281] 23. The method
according to item 22, wherein the synthetic ester is added in an
amount from about 5 wt.-% to about 50 wt.-%, from about 10 wt.-% to
about 40 wt.-%, from about 15 wt.-% to about 35 wt.-% based on the
amount of the lubricating base oil. [0282] 24. The method according
to item 22 or 23, wherein the synthetic ester is added after the
lubricating base oil is present in the equipment. [0283] 25. The
method according to any one of items 22 to 24, wherein the
synthetic ester is a diester of a dicarboxylic acid. [0284] 26. The
method according to any one of items 22 to 25, wherein the diester
of the dicarboxylic acid is selected from the group consisting of
di-(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof, and preferably is di-(isopropylheptyl)-adipate (DPHA).
[0285] 27. A lubricating composition comprising [0286] (i) at least
one base oil selected from a Group I oil according to the API
classification, [0287] (ii) and a diester of the dicarboxylic acid
is selected from the group consisting of
di(isopropylheptyl)-adipate (DPHA), di-isodecyl adipate (DIDA),
diisotridecyl adipate (DITA), diisononyladipate (DNA) or mixtures
thereof, wherein the diester of the dicarboxylic acid is preferably
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof and more preferably is
di-(isopropylheptyl)-adipate (DPHA), and [0288] (iii) optional
further additives. [0289] 28. A lubricating composition comprising
[0290] (i) at least one base oil selected from a Group I, Group II
oil according to the API classification, or a mixture thereof
[0291] (ii) and a diester of the dicarboxylic acid is selected from
the group consisting of di(isopropylheptyl)-adipate (DPHA),
di-isodecyl adipate (DIDA), diisotridecyl adipate (DITA),
diisononyladipate (DNA) or mixtures thereof, wherein the diester of
the dicarboxylic acid is preferably di-(isopropylheptyl)-adipate
(DPHA), diisononyladipate (DNA) or mixtures thereof and more
preferably is di-(isopropylheptyl)-adipate (DPHA), and [0292] (iii)
optional further additives. [0293] 29. Use of a lubricating
composition for reducing the formation of deposits, wherein the
composition comprises [0294] (i) at least one lubricating base oil,
and [0295] (ii) at least one synthetic ester, wherein the synthetic
ester is a diester of the dicarboxylic acid is selected form the
group consisting of di-(isopropylheptyl)-adipate (DPHA), diisodecyl
adipate (DIDA), diisotridecyl adipate (DITA), diisononyladipate
(DNA) or mixtures thereof, and preferably is
di-(isopropylheptyl)-adipate (DPHA), diisononyladipate (DNA) or
mixtures thereof, and more preferably is
di-(isopropylheptyl)-adipate (DPHA).
* * * * *