U.S. patent application number 12/272934 was filed with the patent office on 2009-12-10 for lubricating oil composition for automobile transmission and lubricating method using same.
This patent application is currently assigned to HYUNDAI MOTOR COMPANY. Invention is credited to Sang Yeob Cha, Hirokazu Saito, Skip Watts.
Application Number | 20090305922 12/272934 |
Document ID | / |
Family ID | 41400856 |
Filed Date | 2009-12-10 |
United States Patent
Application |
20090305922 |
Kind Code |
A1 |
Cha; Sang Yeob ; et
al. |
December 10, 2009 |
LUBRICATING OIL COMPOSITION FOR AUTOMOBILE TRANSMISSION AND
LUBRICATING METHOD USING SAME
Abstract
The present invention relates to an automatic transmission
lubricating oil composition, and particularly to an automatic
transmission lubricating oil composition comprising an oil of
lubricating viscosity, an ashless dispersant, an anti-oxidant, a
phosphorus-based anti-wear agent and a friction-modifier, wherein
more than 310 ppm of phosphorus is contained, thereby being useful
for lubricating or operating an automatic transmission comprising a
transmission clutch using a slip lock-up torque converter and a
paper based clutch material and a planetary gear system, especially
six-speed automatic transmission.
Inventors: |
Cha; Sang Yeob;
(Gyeonggi-do, KR) ; Watts; Skip; (Long Valley,
NJ) ; Saito; Hirokazu; (Westfield, NJ) |
Correspondence
Address: |
EDWARDS ANGELL PALMER & DODGE LLP
P.O. BOX 55874
BOSTON
MA
02205
US
|
Assignee: |
HYUNDAI MOTOR COMPANY
Seoul
KR
KIA MOTORS CORPORATION
Seoul
KR
INFINEUM KOREA LTD
Seoul
KR
|
Family ID: |
41400856 |
Appl. No.: |
12/272934 |
Filed: |
November 18, 2008 |
Current U.S.
Class: |
508/186 ;
508/283; 508/287; 508/421 |
Current CPC
Class: |
C10M 2223/043 20130101;
C10M 2215/28 20130101; C10N 2030/76 20200501; C10N 2030/06
20130101; C10M 2219/06 20130101; C10N 2040/042 20200501; C10M
169/04 20130101; C10M 2215/064 20130101; C10M 2215/08 20130101;
C10N 2030/02 20130101; C10N 2030/10 20130101; C10M 2207/10
20130101 |
Class at
Publication: |
508/186 ;
508/421; 508/287; 508/283 |
International
Class: |
C10M 139/00 20060101
C10M139/00; C10M 141/10 20060101 C10M141/10; C10M 133/46 20060101
C10M133/46; C10M 133/44 20060101 C10M133/44 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 9, 2008 |
KR |
10-2008-0053833 |
Claims
1. A lubricating oil composition for a six-speed transmission
having a slipping torque converter clutch and Ravigneaux gear set,
the composition comprising: 100 weight parts of an oil of
lubricating viscosity; 0.5-5 weight parts of an ashless dispersant;
0.05-5 weight parts of an anti-oxidant; 0.03-4.75 weight parts of a
phosphorus-based anti-wear agent; and 0.05-5 weight parts of a
friction modifier, wherein phosphorus is contained at least 310
parts per million.
2. The lubricating oil composition of claim 1, wherein the oil of
lubricating viscosity is selected from the group consisting of a
Group II oil, a Group III oil, a Group IV oil, a Group V oil and a
mixture thereof.
3. The lubricating oil composition of claim 1, wherein the ashless
dispersant is selected from the group consisting of (a) a
long-chain substituted hydrocarbil succinimide or hydrocarbil
succinamide, (b) a mixed ester/amide of a long-chain
hydrocarbil-substituted succinic acid, (c) a hydroxyester of a
long-chain hydrocarbil-substituted succinic acid, and (d) a Mannich
condensation product of a long-chain hydrocarbil-substituted
phenol, formaldehyde and polyamine.
4. The lubricating oil composition of claim 1, wherein the ashless
dispersant is a long-chained alkenyl succinimide.
5. The lubricating oil composition of claim 1, wherein the
anti-oxidant is an aromatic amine or a hindered phenol.
6. The lubricating oil composition of claim 1, wherein the
phosphorus-based anti-wear agent is an organic phosphite or an
amine salt of phosphorus acid.
7. The lubricating oil composition of claim 1, wherein the
phosphorus-based anti-wear agent is prepared by reacting phosphorus
acid with a polyamine-based ashless dispersant.
8. The lubricating oil composition of claim 1, wherein the friction
modifier is selected from the group consisting of fatty acid
amides, fatty epoxides, fatty amines, borated glycerol esters,
alkoxylated fatty amines, borated alkoxylated amines, fatty
imidazolines, condensation products of carboxylic acids and
anhydrides with polyamines.
9. The lubricating oil composition of claim 1, wherein the friction
modifier is a reaction product of 3-octadecenyl succinic acid
anhydride and a polyamine.
10. The lubricating oil composition of claim 1, which has a
kinematic viscosity at 100.degree. C. of 5.2 cSt or higher and a
-40.degree. C. Brookfield viscosity of 12,000 cP or lower.
11. A method for lubricating a six speed automatic transmission
having a slipping torque converter clutch and Ravigneaux gear set
comprising supplying to said transmission the lubricating oil
composition of claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. .sctn.119(a) the
benefit of Korean Patent Application No. 10-2008-0053833 filed Jun.
9, 2008, the entire contents of which are incorporated herein by
reference.
BACKGROUND
[0002] (a) Technical Field
[0003] The present invention relates to a lubricating oil
composition for automatic transmissions and a method of lubricating
automatic transmission using the lubricating oil.
[0004] (b) Background Art
[0005] The continuing need for more energy efficient vehicles has
driven transmission builders to design ever more sophisticated
transmissions that can consume less energy. A recent trend is that
transmissions are designed so as to meet the following
requirements: (a) higher number of fixed speed ratios; (b) torque
converter clutches which are applicable even during aggressive
driving (i.e., meaning the torque converter clutch is engaged at
least 25% of the time for which the vehicle is in motion); (c) more
compact shifting clutches; and (d) more sophisticated planetary
gear set designs such as Ravigneaux and overall architecture as in
the Lepelletier system, which make it to difficult to lubricate the
transmissions while making them more energy efficient.
[0006] In order to provide efficient operation and energy
efficiency, transmissions must have a specific design that allow a
lubricating oil composition to be supplied to the transmissions in
a manner so as to operate the transmissions correctly for a long
time (mileage accumulation).
[0007] For example, the torque converter clutches need to be
applied a fluid with exceptionally good friction characteristics
and durability. The compact shifting clutches need to be applied
with a fluid with excellent high energy friction durability. And,
the planetary gear sets need to be applied with a fluid with
excellent anti-wear characteristics. This is especially true in
case of the torque converter clutches applicable to aggressive
driving, more compact shifting clutches; and more sophisticated
planetary gear sets.
[0008] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention and therefore it may contain information that does not
form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY OF THE DISCLOSURE
[0009] In one aspect, the present invention provides lubricating
oil compositions for use in an automobile transmission, whose
compositions comprise an oil of lubricating viscosity; an ashless
dispersant; an anti-oxidant; a phosphorus-based anti-wear agent;
and a friction modifier, wherein the lubricating oil composition
contains at least 310 parts per million of phosphorus. A
non-limiting example of the transmission may be a six speed energy
efficient automatic transmission comprising a slipping torque
converter, shifting clutches using paper based clutch materials and
planetary gear systems.
[0010] In another aspect, the present invention provides methods
for lubricating an automobile transmission by supplying the
above-described compositions to the transmission.
[0011] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g. fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0012] The above and other features of the invention are discussed
infra.
DETAILED DESCRIPTION
[0013] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the drawings attached hereinafter, wherein like
reference numerals refer to like elements throughout. The
embodiments are described below so as to explain the present
invention by referring to the figures.
[0014] Unless described otherwise, all the numerical values used
herein regarding an amount of an ingredient, a reaction condition,
a dimension, a physical property and a process parameter should be
understood as somewhat variable by the term of "about", and thus
can be changed depending on the desired properties. At least, as an
intention of ensuring the application of equivalent principle, each
of numerical value described herein should be interpreted in view
of the number of significant digits and the typical approximation
method. Further, all the numerical ranges herein should be
understood as comprising any smaller ranges falling within the
range described herein. For example, a range "1-10" should be
interpreted to comprise any smaller range having a lower limit of 1
or higher and an upper limit of 10 or lower (e.g., 5.5-10). Any
patents or academic papers described below are hereby incorporated
herein by reference in its entirety.
[0015] As used herein, the term of "hydrocarbil substitution group"
or "hydrocarbil group" is used in the present invention as
typically understood by one skilled in the art. In particular, this
refers to a group that shows a dominant hydrocarbon property and
includes carbon atoms attached directly to the other part of
molecule. Examples of hydrocarbil group include any substitution
group that causes no change in dominant hydrocarbon property of
hydrocarbon group (such as alkyl and alkenyl group), cycloalkyl
group and a main substitution group. The hydrocarbil group can be a
hetero atom such as sulfur, oxygen and nitrogen provided the
hydrocarbon property is not changed.
[0016] In one aspect of the present invention, as discussed, there
is provided a lubricating oil composition comprising an oil of
lubricating viscosity, an ashless dispersant, an anti-oxidant, a
phosphorus-based anti-wear agent and a friction-modifier along with
more than 310 ppm of phosphorus. The lubricating oil composition is
useful for lubricating and operating various types of
transmissions, including an automatic transmission comprising a
transmission clutch using a slip lock-up torque converter and a
paper based clutch material and a planetary gear system. One of the
examples of such transmissions may be a six-speed automatic
transmission.
[0017] The oil of lubricating viscosity may comprise various oils
of lubricating viscosity such as at least one natural oil, at least
one synthetic oil or a mixture thereof. In a non-limiting
embodiment of the present invention, the oil of lubricating
viscosity is contained in a large amount (i.e., more than about 50
wt %). The oil of lubricating viscosity is contained in the amount
of preferably 75-95 wt %, and more preferably 80-95 wt % relative
to the total weight of the lubricating oil composition.
[0018] Examples of the natural oil may include animal oils and
vegetable oils as well as mineral lubricating oils such as liquid
petroleum oils and solvent treated or acid-treated mineral
lubricating oils of paraffinic, naphthenic or mixed
paraffinic/naphthenic types which may be further refined by hydro
cracking or hydro finishing processes.
[0019] Examples of the synthetic lubricating oil may include
hydrocarbon oils and halo-substituted hydrocarbon oils such as
polymerized and interpolymerized olefins, also known as
polyalphaolefin; polyphenyl; alkylated diphenyl ether; and
alkylated diphenyl sulfide and derivatives, analogs and homologues
of thereof. Other examples of the synthetic lubricating oils may
include various esters of alcohols and dicarboxylic acids and
esters prepared by using C.sub.4-C.sub.15 monocarboxylic acids and
polyols or polyol ethers.
[0020] The aforementioned natural oils and synthetic oils can be
unrefined, refined or re-refined oils. As used herein, the term
"unrefined oil" refers to an oil that can be obtained from a
natural or a synthetic source without a purification process. As
used herein, the term "refined oil" refers to an oil that is
treated in a purification process for improving at least one
properties. The term "re-refined oil" refers to an oil that is
treated in at least two purification processes for improving at
least one properties. For example, the oxidative stability of an
oil can be improved by hydrogenation.
[0021] In a non-limiting embodiment, examples of the oil of
lubricating viscosity may include II group oil, III group oil, IV
group oil, V group oil, which are defined in API Base Oil
Interchangeability Guidelines, and a mixture thereof. Appropriate
examples of II group oil and III group oil are Yubase 3 and Yubase
6, respectively (Yubase is a trademark of SK Energy Co., Ltd.).
Further, appropriate examples of IV group oil and V group oil are a
poly-alpha-olefin and an ester, respectively.
[0022] The oil of lubricating viscosity can be a singular-viscosity
oil or a mixture of a high-viscosity oil and a low-viscosity oil.
In a non-limiting embodiment, the oil of lubricating viscosity may
have a kinematic viscosity of about 2-8 mm.sup.2/sec(cSt) of
100.degree. C. A total lubricating oil composition can be prepared
so that viscosity at 100.degree. C. can be about 5.0-6.0
mm.sup.2/sec, for example about 5.3-5.5 mm.sup.2/sec. A total
lubricating oil composition can be prepared so that a Brookfield
viscosity (ASTM D-2983) at -40.degree. C. can less than 12,000 cP,
for example less than 10,000 cp.
[0023] In a non-limiting embodiment, the ashless dispersant may be
included in the amount of 0.5-5.0 weight parts, such as 1.0-4.0
weight parts or 2.0-3.0 weight parts relative to 100 weight parts
of the oil.
[0024] Examples of appropriate ashless dispersant include a
long-chained (comprising more than 40 carbons) substituted
hydrocarbil succinimide or hydrocarbil succinamide, a mixed
ester/amide of a long-chained (comprising more than 40 carbons)
hydrocarbil-substituted succinic acid, hydroxyester of a long-chain
hydrocarbil-substituted succinic acid and a long-chained
(comprising more than 40 carbons) hydrocarbil-substituted phenol,
Mannich condensation product of formaldehyde and polyamine, and a
mixture thereof.
[0025] In a non-limiting embodiment, examples of the ashless
dispersant include a long-chained alkenyl succinimide, and
non-cyclic hydrocarbil-substituted succinimide prepared by using
various amines or amine derivatives disclosed in patents.
Phosphoric acid (or its anhydride) and borated alkenyl succinimide
are highly compatible (miscible) with elastomeric seal prepared by
using fluoro-elastomer and silicon-containing elastomer, thus being
appropriate for the present invention. Polyisobutenyl succinimide
(where the polyisobutenyl substitution group comes from
polyisobutene having a number average molecular weight of
500-5,000, for example 800-2500), which is prepared by using
polyisobutenyl succinic acid anhydride and alkylene polyamine (for
example, triethylene tetramine or tetraethylene pentamine), is
appropriate for the present invention. The dispersants can,
preferably, be post-treated with various known materials as
disclosed in, for example, U.S. Pat. Nos. 3,254,025, 3,502,677 and
4,857,214.
[0026] According to the present invention, a lubricating
composition may comprise at least one anti-oxidant. An anti-oxidant
of the present invention is well known to one skilled in the art.
In a non-limiting embodiment, anti-oxidants include two types of
compounds, i.e., an aromatic amine compound and a hindered phenol
compound. Examples of appropriate aromatic amine include aromatic
triazole, phenothiazine, diphenyl amine, an alkyl diphenyl amine
comprising at least one substitution group with 16 or less carbon
atoms, phenyl-alpha-naphthyl amine, phenyl-beta-naphthyl amine and
alkyl or aryl-substituted phenyl-alpha-naphthyl amine.
[0027] In a non-limiting embodiment, aromatic amine is a diphenyl
amine which is alkylated with nonene (C9). This is a mixture of
monoalkylated and dialkylated diphenyl amines, where the
substitution group is a branched C.sub.9. This compound is
commercially available under the trademark of Naugalube 438L
(Chemtura Corporation).
[0028] Examples of the hindered phenol include ortho-alkylated
phenol-based compounds such as 2,6-di-tertiary-butyl phenol,
4-methyl-2,6-di-tertiary-butyl phenol, 2,4,6-tri-tertiary-butyl
phenol and analogs or homologues thereof. Other examples of
hindered phenol include butylated hydroxyl toluene (BHT), butylated
hydroxyl anisole (BHA) and derivatives thereof. Examples of
hindered phenol also include methylene bridged alkyl phenol that
can be used alone or in combination with other hindered phenol or
stereo-hindered non-crosslinked phenol-based compound. Examples of
suitable methylene bridged phenol include
4,4'-methylenebis(6-tertiary-butyl-o-cresol), 4,4'-methylenebis
(4-methyl-6-tertiary-butylphenol) and
4,4'-methylenebis(2,6-di-tertiary-butylphenol) and derivatives
thereof as well as a mixture of two or more such mononuclear
phenolic compounds are also suitable.
[0029] Suitably, the anti-oxidant may be contained in the amount of
about 0.05-5.0 weight parts, for example about 0.1-3.0 weight parts
or about 0.25-2.0 weight parts relative to 100 weight parts of the
oil.
[0030] According to the present invention, a lubricating oil
composition may comprise at least one phosphorus-based anti-wear
agent. The phosphorus-based anti-wear agent is contained in the
amount of 0.03-4.75 weight parts relative to 100 weight parts of
the oil. Examples of the phosphorus-based anti-wear agent include
the organic ester of a phosphorus acid, such as an amine salt of an
organic phosphite or a phosphorus acid.
[0031] Appropriate organic phosphite is well known to one skilled
in the art. Organic phosphite appropriate in the present invention
has the Formula 1:
##STR00001##
[0032] wherein R.sub.1 and R.sub.2 are independently
C.sub.1-C.sub.18 alkyl group or hydrogen provided that R.sub.1 and
R.sub.2 are not hydrogen at the same time. An alkyl group can be
linear or branched, and comprise heteroatoms such as nitrogen,
oxygen and sulfur. Appropriate examples of organic phosphite
include dibutyl hydrogen phosphite
(R.sub.1.dbd.R.sub.2.dbd.C.sub.4H.sub.9), di-2-ethylhexyl hydrogen
phosphite (R.sub.1.dbd.R.sub.2.dbd.2-ethylhexyl), dioleyl hydrogen
phosphite (R.sub.1.dbd.R.sub.2=oleyl) and mono-butyl hydrogen
phosphite (R.sub.1.dbd.C.sub.4H.sub.9, R.sub.2.dbd.H).
[0033] In a non-limiting embodiment, an organic phosphite is
reacted with an ashless dispersant, thereby improving its
solubility and stability.
[0034] In a non-limiting embodiment, the phosphorus-based anti-wear
agent can be prepared by producing amine salt of phosphorus acid.
Phosphorus acid (H.sub.3PO.sub.3) can be represented as Formula I,
where R.sub.1.dbd.R.sub.2.dbd.H. These compounds are conventionally
prepared by reacting phosphorus acid with a polyamine-based ashless
dispersant or in the presence of boric acid. U.S. Pat. No.
4,857,214 incorporated herein for the reference discloses such
preparation method.
[0035] According to the present invention, a lubricating oil
composition may comprise at least one friction-modifier.
Appropriate friction-modifier is well known to one skilled in the
art. U S. Pat. No. 4,792,410 discloses examples of appropriate
friction-modifier. Examples of appropriate friction-modifier
include without limitation a fatty acid amide, a fatty epoxide, a
fatty amine, a borated glycerol ester, an alkoxylated fatty amine,
a borated alkoxylated amine, a fatty imidazoline and a condensation
product of carboxylic acid or anhydride and polyamine.
[0036] Commercially available fatty acid amides can be used in the
present invention, and non-limiting examples of such material
include stearamide and oleamide. Normally, an acid group include
about 10-20 carbon atoms.
[0037] Examples of a fatty epoxide appropriate for the present
invention include a compound prepared by reacting a per-oxidizing
agent (e.g. per-acetic acid) with olefin. A typical olefin
appropriate for the preparation of a friction-modifier is a linear
olefin including about 10-20 carbon atoms and a double bond at the
end of the chain (for example, between the first and the second
carbons. Non-limiting examples of an appropriate olefin include
1,2-epoxyhexadecane, 1,2-epoxyoctadecane and a mixture thereof. A
borated fatty epoxide can be prepared by reacting a fatty epoxide
with a borating agent such as boric acid.
[0038] Non-limiting examples of an appropriate borated glycerol
ester include an ester of glycerol and a long-chained fatty acid
such as stearic acid and oleic acid. A borated glycerol ester can
be prepared by reacting one mole of an acid with one mole of
glycerol to provide two free hydroxyl groups. Examples of such
material include glycerol mono-oleate. Hydroxyl borate ester can be
prepared by reacting such diol-containing ester with boric
acid.
[0039] An alkoxylated fatty amine, a widely known
friction-modifier, is bis-(mono ethoxylate) of C10-C20 long-chained
amine. This is manufactured by Akzo Nobel (Amsterdam) and on the
market as Ethomeen. Examples of such material include
bis(2-hydroxyethyl)tallowamine, bis(2-hydroxyethyl)oleylamine and
bis(2-hydroxyethyl)octadecylamine. A borated alkoxylated amine can
be prepared by reacting bis alkoxylated amine with boric acid. For
instance, a product prepared by reacting one moles of alkoxylated
amine and diethoxylate with 0.5-2.0 moles of boric acid can be used
as a friction-modifier.
[0040] A fatty imidazoline is a condensation product of a fatty
acid and diamine or polyamine. Examples of appropriate acid include
natural acids such as decanoic acid, oleic acid, stearic acid,
isostearic acid, palmitic acid, myristic acid, linoleic acid,
lauric acid and acids resulting from tallow or palm oil. Examples
of appropriate amine include tetraethylene pentamine and
polyamine.
[0041] The aforementioned imidazoline can be prepared by conducting
the condensation between carboxylic acid or anhydride and
polyamine. However, this condensation can result in the production
of a simple amide when the reaction condition is relatively milder,
or the production of succinamide when succinic acid anhydride-based
reactants are used.
[0042] Other appropriate friction-modifier is produced by the
reaction between alkyl-substituted succinic acid anhydride and
polyamine. Examples of such friction-modifier include a
condensation product of 3-octadecenyl succinic acid anhydride and
diethylene triamine or tetraethylene pentamine. The preparation
method is disclosed in U.S. Pat. No. 5,840,663.
[0043] Any combination of the aforementioned friction-modifiers can
also be used in the present invention.
[0044] Preferably, about 0.05-5.0 weight parts, more preferably,
about 0.1-4.0 weight parts of the friction-modifier may be
contained relative to 100 weight parts of oil.
[0045] In the present invention, a lubricating oil composition
comprises 310 ppm or more of phosphorus. The typical lubricating
oil composition comprises less than 1500 ppm of phosphorus.
Phosphorus may come from at least one of the components of the
composition as long as the amount of phosphorus is at least 310 ppm
relative to the total amount of the composition.
[0046] A lubricating oil composition of the present invention may
further comprise various additional components. Examples of such
additional components include the followings without limitation: a
viscosity modifier, an anticorrosive, an antifoaming agent, a seal
swell agent, a pour-point depressant, a detergent, a fluidizer and
a dye.
[0047] Viscosity modifiers and dispersants are well known to one
skilled in the art. Their examples include polymethacrylate,
polyacrylate, polyolefin, styrene-maleic acid anhydride copolymer
and analogous homopolymer, copolymer and graft copolymer. In a
non-limiting embodiment of the present invention, examples of
Viscosity modifier include polymethacrylate, which are manufactured
by RohMax and on the market as Acryloid and Viscoplex series
polymer manufactured.
[0048] A lubricating oil composition shows a kinematic viscosity of
5.2 cSt or higher (preferably 5.2-6.0 cSt) at 100.degree. C. and
Brookfield viscosity of 12,000 cP or lower (preferably 3,000-12,000
cP) at -40.degree. C.
[0049] In another aspect, as discussed above, the present invention
provides a method for lubricating automobile transmissions using
the above-described lubrication oil compositions. As discussed
above, the kind and size of the transmissions are not limited. The
above-described lubricating oil compositions may be supplied to the
transmissions in a way known to those skill in the art.
EXAMPLES
[0050] The following examples illustrate the invention and are not
intended to limit the same. As used herein, "parts" and "%" are
based on the weight unless described otherwise.
Examples 1-5
[0051] In Example 1, a lubricating oil composition according to the
present invention was prepared by a conventional method with the
following components.
[0052] (1) An oil of lubricating viscosity: 100 weight parts of API
III group oil;
[0053] (2) An ashless dispersant: 1.50 weight parts of a dispersant
prepared by reacting polyisobutenyl(MW: about 1000)-substituted
succinic acid anhydride with alkylene polyamine;
[0054] (3) A friction-modifier comprising: (a) 3.60 weight parts of
a friction-modifier prepared by reacting 3-octadecenyl succinic
acid anhydride with a polyamine; (b) 0.10 weight parts of
carboxylic acid friction-modifier; (c) 0.10 weight parts of an
alkyl thio ether ester friction-modifier; and (d) 0.09 weight parts
of a fatty acid amide friction-modifier;
[0055] (4) An anti-oxidant comprising: (a) 0.25 weight parts of a
hindered phenol an anti-oxidant; and (b) 0.75 weight parts of an
alkyl diphenylamine anti-oxidant; and
[0056] (5) A phosphorus-based anti-wear agent: 4.00 weight parts of
succinic acid anhydride substituted with polyisobutenyl(MW: about
2000) reacted with a mixture of monoalkyl and dialkyl phosphite
such that the final product after the additional reaction with
polyamine may comprise about 0.8 wt % of phosphorus and a total
lubricating oil composition may comprise more than 330 ppm of
phosphorus.
[0057] The following additional components were added to the
composition: (1) 0.10 weight parts of an anticorrosive; (2) 0.20
weight parts of calcium dispersant; (3) 1.50 weight parts of a
heterocyclic seal swelling agent; (4) 2.00 weight parts of a
polymethacrylate Viscosity modifier; and (5) 200 ppm of an
antifoaming agent.
[0058] In Examples 2-5, lubricating oil compositions according to
the present invention were prepared by the method used in Example 1
except that the components shown in Table 1 were used with the
following respective oils of lubricating viscosity: (a) 4cSt III
group (Example 2); (b) 4cSt III group (Example 3); (c) 3cSt III
group (Example 4); and (d) 3cSt III group (Example 5).
[0059] As an ashless dispersant, 950 MW PIBSA/PAM was used in
Examples 2 and 3 and 2000 MW PIBSA/PAM was used in Examples 4 and
5.
[0060] As an anti-oxidant, (i) alkyl diphenyl amine and (ii)
hindered phenol were used in Examples 2-5.
[0061] As a phosphorus-based anti-wear agent, a dibutyl hydrogen
phosphate was used in Example 2, a diphenyl hydrogen phosphate was
used in Example 3, and 950 MW PIBSA/PAM dispersant reacted with
H.sub.3PO.sub.3 and H.sub.3PO.sub.3 was used in Examples 4 and
5.
[0062] As a friction-modifier, a product prepared by reacting
isostearic acid and tetraethylene pentamine was used in Example 2,
(i) a product prepared by reacting 3-octadecenyl succinic acid
anhydride and diethylene triamine and (ii) a diethoxylated tallow
amine were used in Example 3, (i) a product prepared by reacting
isostearic acid and tetraethylene pentamine and (ii)
1-hydroxyethyl-2-heptadecyl imidazoline were used in Example 4 and
(i) a product prepared by reacting 3-octadecenyl succinic acid
anhydride and diethylene triamine and (ii) diethoxylated tallow
amine were used in Example 5.
TABLE-US-00001 TABLE 1 Example 2* Example 3* Example 4* Example 5*
(parts by (parts by (parts by (parts by weight % on an weight % on
an weight % on an weight % on an Components oil-free basis)
oil-free basis) oil-free basis) oil-free basis) Ashless dispersant
2.50 2.50 2.0 2.0 Anti-oxidant (i) 0.75 (i) 0.75 (i) 0.75 (i) 0.75
(ii) (ii) 0.25 (ii) 0.25 (ii) 0.25 0.25 Phosphorus-based 0.25 0.18
4.75 4.05 anti-wear agent Friction Modifier 2.0 (i) 2.0 (i) 2.0 (i)
2.0 (ii) 0.2 (ii) 0.5 (ii) 0.2 *relative to 100 weight parts of
oil
[0063] Performance tests were conducted for the lubricating oil
composition prepared in Example 1. As a Comparative Example, the
same tests were conducted by using commercially available 4-speed
automatic transmission oil used in a car manufacturing plant and
DiaQueen SP-III ATF of Mitsubishi Motor Company. The results are
presented in Table 2.
TABLE-US-00002 TABLE 2 Performance test Tests Example 1 Comp. Ex. 1
Phosphorus content [ppm] 330 240 Wear FZG A/3.3/90.sup.a 13 11
Failure load stage Friction Anti-shudder durability.sup.b 384 168
hours to failure SAE NO. 2 MERCON method 0.125 0.120 static
friction coefficient.sup.c JASO method.sup.d 0.118 0.110 static
friction coefficient [.mu.t] Ratio of friction coefficients 0.95
1.00 [.mu.0/.mu.d] Oxidation DKA method.sup.e [TAN increase] 0.65
0.97 Viscosity Kinematic viscosity at 100.degree. C. 5.41 7.53 ASTM
D-445[mm.sup.2/s(cSt)] Brookfield viscosity at -40.degree. C. 8,850
15,600 ASTM D-2983[cP] .sup.aAs per method DIN 51354-2. .sup.bAs
per JASO method M-349-2001 using Dynax D512 friction discs.
.sup.cAs per Ford MERCON Specification, "MERCON .RTM. Automatic
Transmission Fluid for Service", January 1997, Appendix 4. using
Borg Warner BW 6100 friction discs. .sup.dAs per method JASO
M-348-2002 using NissekiWarner NW461E friction discs. .sup.eAs per
CEC-L-48, 170.degree. C. for 192 hours.
[0064] Table 2 shows that lubricating oil composition of Example 1
is superior to that of Comparative Example 1 in all the tests.
[0065] Wear: FZG test was preformed for evaluating the capability
of the oils of preventing gear scuffing. The lubricating oil of
Example 1 was superior to the oil of Comparative Example 1 in this
test. The oil of Comparative Example 1 failed at the 11.sup.th
level while that of Example 1 failed at 13.sup.th level.
[0066] Friction: According to JASO M-349-2001 test, the lubricating
oil of Example 1 showed a remarkable increase in anti-shudder
durability (384 hours) as compared to the oil of Comparative
Example 1 (168 hours). This means the lifespan of torque converter
clutch can be increased when the lubricant of Example 1 is used.
Further, according to SAE #2 test, static friction coefficients
were increased in Example 1. This means that higher torque capacity
can be achieved under higher load conditions (e.g., towing) by
using the lubricant of Example 1.
[0067] Oxidation resistance: The lubricating oil of Example 1 was
superior to the oil of Comparative Example 1 in the resistance to
oxidation. Lower degree of TAN (total acid number) increase means
better oxidative stability and improved durability.
[0068] Viscosity: The 100.degree. C. viscosity and -40.degree. C.
Brookfield viscosity of the lubricating oil of Example 1 were lower
than those of Comparative Example 1. As a result, the lubricating
oil of Example 1 maintained an appropriate thickness on
hydrodynamic lubricating parts of transmissions such as a bearing,
and increases total energy efficiency of transmissions.
[0069] As described above, the lubricating oil compositions
according to the present invention are useful for lubricating and
operating various types of automobile transmissions including one
which comprises a transmission clutch using a slip lock-up torque
converter and a paper based clutch material and an planetary gear
system, especially a six-speed automatic transmission.
[0070] The invention has been described in detail with reference to
preferred embodiments thereof. However, it will be appreciated by
those skilled in the art that changes may be made in these
embodiments without departing from the principles and spirit of the
invention, the scope of which is defined in the appended claims and
their equivalents.
* * * * *