U.S. patent application number 12/144010 was filed with the patent office on 2009-12-24 for friction modifiers for slideway applications.
This patent application is currently assigned to AFTON CHEMICAL CORPORATION. Invention is credited to Mark T. Devlin, Katie A. Hudson, Helen T. Ryan.
Application Number | 20090318319 12/144010 |
Document ID | / |
Family ID | 40897509 |
Filed Date | 2009-12-24 |
United States Patent
Application |
20090318319 |
Kind Code |
A1 |
Devlin; Mark T. ; et
al. |
December 24, 2009 |
FRICTION MODIFIERS FOR SLIDEWAY APPLICATIONS
Abstract
A slideway lubricating oil composition, additive concentrate,
method of lubricating sliding parts. The lubricating oil includes a
base oil; a metal-free friction modifier; and a metal-free,
sulfur-free, phosphorus containing anti-wear/extreme pressure
agent. The lubricating oil provides a lower coefficient of friction
for non-metal sliding surfaces than for metal sliding surfaces.
Inventors: |
Devlin; Mark T.; (Richmond,
VA) ; Ryan; Helen T.; (London, GB) ; Hudson;
Katie A.; (Berkshire, GB) |
Correspondence
Address: |
AFTON CHEMICAL CORPORATION;LUEDEKA, NEELY & GRAHAM, PC
P.O. BOX 1871
KNOXVILLE
TN
37901
US
|
Assignee: |
AFTON CHEMICAL CORPORATION
Richmond
VA
|
Family ID: |
40897509 |
Appl. No.: |
12/144010 |
Filed: |
June 23, 2008 |
Current U.S.
Class: |
508/287 ;
508/399; 508/433; 508/460; 508/545; 508/564 |
Current CPC
Class: |
C10M 2203/1025 20130101;
C10N 2030/56 20200501; C10M 141/10 20130101; C10M 2219/106
20130101; C10M 2223/00 20130101; C10N 2040/06 20130101; C10M
2205/00 20130101; C10M 2219/068 20130101; C10M 2215/28 20130101;
C10M 2207/262 20130101; C10M 2215/02 20130101; C10M 2223/06
20130101; C10N 2030/40 20200501; C10M 2223/045 20130101; C10N
2070/02 20200501; C10M 163/00 20130101; C10N 2020/02 20130101; C10M
2207/028 20130101; C10N 2030/06 20130101; C10M 2217/043 20130101;
C10M 2219/046 20130101; C10M 2207/283 20130101; C10M 2215/224
20130101; C10M 2223/045 20130101; C10N 2010/04 20130101; C10M
2219/068 20130101; C10N 2010/12 20130101; C10M 2219/046 20130101;
C10N 2010/04 20130101; C10M 2207/262 20130101; C10N 2010/04
20130101; C10M 2207/028 20130101; C10N 2010/04 20130101; C10M
2219/068 20130101; C10N 2010/12 20130101; C10M 2223/045 20130101;
C10N 2010/04 20130101; C10M 2219/046 20130101; C10N 2010/04
20130101; C10M 2207/262 20130101; C10N 2010/04 20130101; C10M
2207/028 20130101; C10N 2010/04 20130101 |
Class at
Publication: |
508/287 ;
508/564; 508/545; 508/433; 508/399; 508/460 |
International
Class: |
C10M 169/04 20060101
C10M169/04; C10M 133/00 20060101 C10M133/00; C10M 137/12 20060101
C10M137/12; C10M 129/70 20060101 C10M129/70; C10M 133/44 20060101
C10M133/44 |
Claims
1. A slideway lubricating oil composition comprising: a base oil; a
metal-free friction modifier; and a metal-free, sulfur-free,
phosphorus containing anti-wear/extreme pressure agent; wherein the
composition provides a lower coefficient of friction for non-metal
sliding surfaces than for metal sliding surfaces.
2. The lubricating oil composition of claim 1, wherein the
metal-free friction modifier comprises an amine-containing,
metal-free friction modifying compound.
3. The lubricating oil composition of claim 1, wherein the
anti-wear/extreme pressure agent comprises dimethyl octadecyl
phosphonate.
4. The lubricating oil composition of claim 1, further comprising a
detergent, wherein the detergent is selected from the group
consisting of a calcium overbased sulfonate, a calcium overbased
phenate, and a calcium overbased salicylate.
5. The lubricating oil composition of claim 1, further comprising a
dispersant, wherein the dispersant is selected from the group
consisting of a succinimide dispersant, a Mannich dispersant, and a
functionalized olefin copolymer dispersant.
6. A slideway lubricating additive composition comprising. a
metal-free friction modifier; and a metal-free, sulfur-free,
phosphorus containing anti-wear/extreme pressure agent; wherein a
lubricant composition containing the additive exhibits a lower
coefficient of friction for non-metal sliding surfaces than for
metal sliding surfaces.
7. The additive composition of claim 6, wherein the metal-free
friction modifier comprises an amine-containing, metal-free
friction modifying compound.
8. The additive composition of claim 6, wherein the
anti-wear/extreme pressure agent comprises dimethyl octadecyl
phosphonate.
9. The additive composition of claim 6, further comprising a
detergent, wherein the detergent is selected from the group
consisting of a calcium overbased sulfonate, a calcium overbased
phenate, and a calcium overbased salicylate.
10. The additive composition of claim 6, further comprising a
dispersant, wherein the dispersant is selected from the group
consisting of a succinimide dispersant, a Mannich dispersant, and a
functionalized olefin copolymer dispersant.
11. A slideway lubricant composition comprising a lubricant base
stock and about 0.01% to about 1.0% by weight of the additive
composition of claim 6.
12. The lubricant composition of claim 11, wherein the lubricant
composition is free of or essentially free of metal-containing
friction modifiers.
13. The lubricant composition of claim 11, wherein the lubricant
composition is free of or essentially free of amine-free and
metal-free friction modifiers.
14. The lubricant composition of claim 11, wherein lubricant
composition is free of or essentially free of metal-containing
phosphorus/sulfur compounds and metal-free sulfur compounds.
15. The lubricant composition of claim 11, wherein lubricant
composition comprises at least one friction modifying additives
selected form the group consisting of metal-free friction
modifiers, amine-containing metal-free friction modifiers, and
metal- and sulfur-free phosphorus compound friction modifiers.
16. The lubricant composition of claim 11, wherein a boundary
friction coefficient measured on non-metal is from 25 to 50 percent
less than a boundary friction coefficient for the same lubricant
composition as measures on metal surfaces.
17. A method of lubricating a non-metal surface of a slideway
component, the method comprising applying a lubricant composition
to the slideway component, the lubricant composition comprising: a
base oil; a metal-free friction modifier; a metal-free,
sulfur-free, phosphorus containing anti-wear/extreme pressure
agent; wherein the composition provides a lower coefficient of
friction for non-metal sliding surfaces than for metal sliding
surfaces.
18. The method of claim 17, wherein the metal-free friction
modifier comprises an amine-containing, metal-free friction
modifying compound.
19. The method of claim 17, wherein the anti-wear/extreme pressure
agent comprises dimethyl octadecyl phosphonate.
20. The method of claim 17, wherein the lubricant composition
includes a detergent selected from the group consisting of 8a
calcium overbased sulfonate, a calcium overbased phenate, and a
calcium overbased salicylate.
21. The method of claim 17, wherein the lubricant composition
includes a dispersant selected from the group consisting of a
succinimide dispersant, a Mannich dispersant, and a functionalized
olefin copolymer dispersant.
Description
TECHNICAL FIELD
[0001] The embodiments described herein relate to lubricant
additives and use of such additives in lubricating oil
formulations, and in particular to additive formulations used for
slideway applications.
BACKGROUND AND SUMMARY
[0002] A slideway is a mechanical guide designed to provide a
device with a track surface that is stable under load (i.e.,
minimal deflection) with a consistent finish for constant
frictional forces, regardless of the rate of movement along the
slideway. Slideways may be used in heavy machine tool applications
as well as in various electronic components such as disk drives for
computers. Other slideways may be included in automotive shifting
mechanisms. In order to prevent stick-slip in slideway applications
friction at low speed (hereinafter referred to as "static
friction") must be lower than friction at high speed (hereinafter
referred to as "dynamic friction"). Surface active agents (friction
modifiers, anti-wear additives and extreme-pressure agents) are
added to oils to reduce friction. The ability of surface active
agents to reduce static friction on metal surfaces is well known.
However, in many slideway applications, plastic surfaces are
commonly used. Lubricant additives that are effective for metal
surfaces may not be effective to reduce friction for plastic
surfaces to levels suitable for protecting the plastic surfaces.
Accordingly, a need exists for effective lubricant compositions and
lubricant additive concentrates that are more suitable for reducing
friction in slideways containing plastic components and/or plastic
sliding surfaces.
[0003] In one embodiment disclosed herein is presented a slideway
lubricating additive useful in lubricating oils for slideway
applications having a non-metal surface to be lubricated. The
lubricating additive includes a metal-free friction modifier; and a
metal-free, sulfur-free, phosphorus containing anti-wear/extreme
pressure agent. The composition provides a lower coefficient of
friction for non-metal sliding surfaces than for metal sliding
surfaces.
[0004] In another embodiment is presented a lubricating oil
composition containing the slideway lubricating additive. The
lubricating oil compositions include a base oil a metal-free
friction modifier; and a metal-free, sulfur-free, phosphorus
containing anti-wear/extreme pressure agent. The composition
provides a lower coefficient of friction for non-metal sliding
surfaces than for metal sliding surfaces.
[0005] Another embodiment provides a method of lubricating a
non-metal surface of a slideway component. The method includes
applying a lubricant composition to the slideway component wherein
the lubricant contains a base oil; and a metal-free friction
modifier; a metal-free, sulfur-free, phosphorus containing
anti-wear/extreme pressure agent. The lubricant composition
provides a lower coefficient of friction for non-metal sliding
surfaces than for metal sliding surfaces.
[0006] Since slideways commonly employ various non-metal surfaces,
such as plastic and polymeric surfaces, lubricants suitable for
friction reduction on non-metal surfaces are critical for
successful lubrication of slideways. Lubricants and additive
packages for lubricants described herein provide surface active
agents that may have similar friction-reducing properties on metal
surfaces but dramatically improve friction-reducing properties on
non-metal surfaces.
[0007] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory only and are intended to provide further
explanation of the embodiments disclosed and claimed.
DETAILED DESCRIPTION OF EMBODIMENTS
[0008] As used herein, the term "hydrocarbon soluble" means that
the compound is substantially suspended or dissolved in a
hydrocarbon material, as by reaction or complexation of a reactive
metal compound with a hydrocarbon material. As used herein,
"hydrocarbon" means any of a vast number of compounds containing
carbon, hydrogen, and/or oxygen in various combinations.
[0009] The term "hydrocarbyl" refers to a group having a carbon
atom directly attached to the remainder of the molecule and having
predominantly hydrocarbon character. Examples of hydrocarbyl groups
include: [0010] (1) hydrocarbon substituents, that is, aliphatic
(e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl,
cycloalkenyl) substituents, and aromatic-, aliphatic-, and
alicyclic-substituted aromatic substituents, as well as cyclic
substituents wherein the ring is completed through another portion
of the molecule (e.g., two substituents together form an alicyclic
radical); [0011] (2) substituted hydrocarbon substituents, that is,
substituents containing non-hydrocarbon groups which, in the
context of the description herein, do not alter the predominantly
hydrocarbon substituent (e.g., halo (especially chloro and fluoro),
hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and
sulfoxy); [0012] (3) hetero-substituents, that is, substituents
which, while having a predominantly hydrocarbon character, in the
context of this description, contain other than carbon in a ring or
chain otherwise composed of carbon atoms. Hetero-atoms include
sulfur, oxygen, nitrogen, and encompass substituents such as
pyridyl, furyl, thienyl and imidazolyl. In general, no more than
two, preferably no more than one, non-hydrocarbon substituent will
be present for every ten carbon atoms in the hydrocarbyl group;
typically, there will be no non-hydrocarbon substituents in the
hydrocarbyl group.
[0013] The disclosure is directed to lubricants and additive
concentrates for lubricant compositions that are effective for
reducing friction in slideway applications incorporating non-metal
surfaces. For the purposes of the disclosure, the term "non-metal"
may include substantially non-porous components made of plastic,
ceramic, polymeric, fiberglass, glass, and composite materials, but
does not include components that are primarily made of metal, i.e.,
more than about 50 weight percent metal.
[0014] In particular, the disclosure provides in one embodiment a
lubricant additive that includes metal-free friction modifiers that
are more effective at reducing friction for non-metal surfaces than
metal-containing friction modifiers. In another embodiment, the
additive includes at least one amine-containing, metal-free
friction modifier that is more effective for reducing friction on
non-metal surfaces than amine-free metal-free friction modifiers.
Yet another exemplary embodiment provides a lubricant additive that
includes metal- and sulfur-free phosphorus compounds that are more
effective for reducing friction on non-metal surfaces than
metal-containing phosphorus/sulfur compounds and metal-free sulfur
compounds.
Friction Modifier Components
[0015] A particularly suitable friction modifiers, according to the
disclosure includes a metal-free, amine-containing friction
modifier according to the following general formula:
##STR00001##
wherein R.sup.1 is an alkyl or alkenyl group containing from about
10 to about 30 carbon atoms and R.sup.2 is a hydroxyalkyl group
containing from about 2 to about 4 carbon atoms. A particularly
suitable metal-free, amine-containing friction modifier may be a
hydroxyalkyl alkenyl glyoxalidine such as
2-(2-heptadec-1-enyl-4,5-dihydroimidazol-1-yl)ethanol available
from Lonza of Allendale, N.J. under the trade name UNAMINE O. The
amount of metal-free, amine-containing friction modifier in the
lubricant composition may range from about 0.01 to about 1.0
percent by weight based on the total weight of the lubricant
composition.
[0016] In addition to the aforementioned metal-free, amine
containing friction modifiers, compositions of the present
disclosure may include additional friction modifiers. Glycerides
may be used alone or in combination with other friction modifiers.
Suitable glycerides may include glycerides of the formula:
##STR00002##
wherein each R is independently selected from the group consisting
of H and C(O)R' where R' may be a saturated or an unsaturated alkyl
group having from 3 to 23 carbon atoms. Examples of glycerides that
may be used include glycerol monolaurate, glycerol monomyristate,
glycerol monopalmitate, glycerol monostearate, and mono-glycerides
derived from coconut acid, tallow acid, oleic acid, linoleic acid,
and linolenic acids. Typical commercial monoglycerides contain
substantial amounts of the corresponding diglycerides and
triglycerides. Any ratio of mono- to di-glyceride may be used,
however, it is preferred that from 30 to 70% of the available sites
contain free hydroxyl groups (i.e., 30 to 70% of the total R groups
of the glycerides represented by the above formula are hydrogen). A
preferred glyceride is glycerol monooleate, which is generally a
mixture of mono, di, and tri-glycerides derived from oleic acid,
and glycerol. Suitable commercially-available glycerides include
glycerol monooleates, which may generally contain approximately 50%
to 60% free hydroxyl groups.
Anti-wear/Extreme Pressure Agents
[0017] In addition to the foregoing friction modifier, lubricant
compositions and additive concentrates according to the disclosure
may also contain metal-free phosphorus anti-wear/extreme pressure
agents. A particularly suitable anti-wear/extreme pressure agent is
a metal-free, sulfur-free phosphorus compound represented by the
following general formula:
##STR00003##
wherein each of R.sup.3 and R.sup.4 is an alkyl group having from
about 1 to about 4 carbon atoms or hydrogen, provided that not both
of R.sup.3 and R.sup.4 are hydrogen, and R.sup.5 is an alkyl or
alkenyl group having from about 6 to about 30 carbon atoms. Useful
phosphonate esters include O,O-di-(primary alkyl)acyclic
hydrocarbyl phosphonates in which the primary alkyl groups are the
same or different each independently containing 1 to 4 carbon atoms
and in which the acyclic hydrocarbyl group bonded to the phosphorus
atom contains 12 to 24 carbon atoms and is a linear hydrocarbyl
group free of acetylenic unsaturation. Exemplary compounds include
O,O-dimethyl hydrocarbyl phosphonates, O,O-diethyl hydrocarbyl
phosphonates, O,O-dipropyl hydrocarbyl phosphonates, O,O-dibutyl
hydrocarbyl phosphonates, O,O-diiso-butyl hydrocarbyl phosphonates,
and analogous compounds in which the two alkyl groups differ, such
as, for example, O-ethyl-O-methyl hydrocarbyl phosphonates,
O-butyl-O-propyl hydrocarbyl phosphonates, and O-butyl-O-isobutyl
hydrocarbyl phosphonates, wherein in each case the hydrocarbyl
group is linear and is saturated or contains one or more olefinic
double bonds, each double bond preferably being an internal double
bond. Suitable compounds include compounds in which both O,O-alkyl
groups are identical to each other. Other suitable compounds
include compounds in which the hydrocarbyl group bonded to the
phosphorus atom contains 16 to 20 carbon atoms. A particularly
suitable phosphonate ester compounds is dimethyloctadecyl
phosphonate. Other examples of suitable phosphonate esters include,
but are not limited to, dimethyl triacontylphosphonate, dimethyl
triacontenylphosphonate, dimethyl eicosylphosphonate, dimethyl
hexadecylphosphonate, dimethyl hexadecenylphosphonate, dimethyl
tetracontenylphosphonate, dimethyl hexacontylphosphonate, dimethyl
dodecylphosphonate, dimethyl dodecenylphosphonate and the like.
Phosphonate esters are described, for example, in U.S. Pat. No.
4,158,633. The amount of anti-wear/extreme pressure agent in
lubricant compositions according to the disclosure may range from
about 0.01 to about 1.0 percent by weight based on a total weight
of the lubricant composition.
Metallic Detergents
[0018] Certain metallic detergents may be included in the additive
package of the for the slideway lubricant according to the
disclosure. A suitable metallic detergent may include an
oil-soluble neutral or overbased salt of alkali or alkaline earth
metal with one or more of the following acidic substances (or
mixtures thereof): (1) a sulfonic acid, (2) a carboxylic acid, (3)
a salicylic acid, (4) an alkyl phenol, and (5) an organic
phosphorus acid characterized by at least one direct
carbon-to-phosphorus linkage. Such an organic phosphorus acid may
include those prepared by the treatment of an olefin polymer (e.g.,
polyisobutylene having a molecular weight of about 1,000) with a
phosphorizing agent such as phosphorus trichloride, phosphorus
heptasulfide, phosphorus pentasulfide, phosphorus trichloride and
sulfur, or white phosphorus and a sulfur halide..
[0019] Suitable salts may include neutral or overbased salts of
magnesium, calcium, or zinc. As a further example, suitable salts
may include magnesium sulfonate, calcium sulfonate, zinc sulfonate,
magnesium phenate, calcium phenate, and/or zinc phenate. See, e.g.,
U.S. Pat. No. 6,482,778.
[0020] Examples of suitable metal-containing detergents include,
but are not limited to, neutral and overbased salts such as a
sodium sulfonate, a sodium carboxylate, a sodium salicylate, a
sodium phenate, a lithium sulfonate, a lithium carboxylate, a
lithium salicylate, a lithium phenate, a magnesium sulfonate, a
magnesium carboxylate, a magnesium salicylate, a magnesium phenate,
a calcium sulfonate, a calcium carboxylate, a calcium salicylate, a
calcium phenate, a potassium sulfonate, a potassium carboxylate, a
potassium salicylate, a potassium phenate, a zinc sulfonate, a zinc
carboxylate, a zinc salicylate, and a zinc phenate. Further
examples include a lithium, sodium, potassium, calcium, and
magnesium salt of an aliphatic carboxylic acid and an aliphatic
substituted cycloaliphatic carboxylic acid and many other similar
alkali and alkaline earth metal salts of oil-soluble organic acids.
A mixture of a neutral or an overbased salt of two or more
different alkali and/or alkaline earth metals can be used.
Likewise, a neutral and/or an overbased salt of mixtures of two or
more different acids can also be used. Particularly suitable metal
detergents useful in the slideway lubricants described herein may
be selected from a calcium overbased sulfonate, a calcium overbased
phenate and a calcium overbased sulfonate.
[0021] While any effective amount of the metallic detergents may be
used to enhance the benefits of this invention, typically these
effective amounts will range from about 0.01 to about 2.0 wt. % in
the finished fluid, or as a further example, from about 0.1 to
about 1.5 wt. % in the finished fluid.
Dispersant Components
[0022] Suitable dispersants may include, but are not limited to, an
oil soluble polymeric hydrocarbon backbone having functional groups
that are capable of associating with particles to be dispersed.
Typically, the dispersants comprise amine, alcohol, amide, or ester
polar moieties attached to the polymer backbone often via a
bridging group. Dispersants may be selected from Mannich
dispersants as described in U.S. Pat. Nos. 3,697,574 and 3,736,357;
ashless succinimide dispersants as described in U.S. Pat. Nos.
4,234,435 and 4,636,322; amine dispersants as described in U.S.
Pat. Nos. 3,219,666, 3,565,804, and 5,633,326; Koch dispersants as
described in U.S. Pat. Nos. 5,936,041, 5,643,859, and 5,627,259,
and polyalkylene succinimide dispersants as described in U.S. Pat.
Nos. 5,851,965; 5,853,434; and 5,792,729. In one embodiment of the
present disclosure, the dispersant may be a polyisobutyl-succinic
anhydride dispersant. The amount of dispersant in the slideway
lubricant composition may range from about 0.01 to about 2.0 weight
percent based on the total weight of the lubricant composition.
Base Oils
[0023] Embodiments of the present disclosure may also include one
or more base oils of lubricating viscosity. Base oils suitable for
use in formulating the compositions, additives and concentrates
described herein may be selected from any of the synthetic or
natural oils or mixtures thereof. The synthetic base oils include
alkyl esters of dicarboxylic acids, polyglycols and alcohols,
poly-alpha-olefins, including polybutenes, alkyl benzenes, organic
esters of phosphoric acids, polysilicone oils, and alkylene oxide
polymers, interpolymers, copolymers and derivatives thereof where
the terminal hydroxyl groups have been modified by esterification,
etherification, and the like.
[0024] Natural base oils include animal oils and vegetable oils
(e.g., castor oil, lard oil), liquid petroleum oils and
hydrorefined, solvent-treated or acid-treated mineral lubricating
oils of the paraffinic, naphthenic and mixed paraffinic-naphthenic
types. Oils of lubricating viscosity derived from coal or shale are
also useful base oils. The base oil typically has a viscosity of
about 2.5 to about 15 cSt and preferably about 2.5 to about 11 cSt
at 100.degree. C.
[0025] In addition to the aforementioned components, embodiments of
the present disclosure may further include one or more optional
additive components, including, but not limited to, corrosion
inhibitors, pour point depressants, antifoam agents, viscosity
index improvers, and mixtures of two or more of the foregoing.
Corrosion Inhibitors
[0026] In some embodiments, copper corrosion inhibitors may
constitute another class of additives suitable for inclusion in the
compositions. Such compounds include thiazoles, triazoles and
thiadiazoles. Examples of such compounds include benzotriazole,
tolyltriazole, octyltriazole, decyltriazole, dodecyltriazole,
2-mercapto benzothiazole, 2,5-dimercapto-1,3,4-thiadiazole,
2-mercapto-5-hydrocarbylthio-1,3,4-thiadiazoles,
2-mercapto-5-hydrocarbyldithio-1,3,4-thiadiazoles,
2,5-bis(hydrocarbylthio)-1,3,4-thiadiazoles, and
2,5-bis(hydrocarbyldithio)-1,3,4-thiadiazoles. Suitable compounds
include the 1,3,4-thiadiazoles, a number of which are available as
articles of commerce, and also combinations of triazoles such as
tolyltriazole with a 1,3,5-thiadiazole such as a
2,5-bis(alkyldithio)-1,3,4-thiadiazole. The 1,3,4-thiadiazoles are
generally synthesized from hydrazine and carbon disulfide by known
procedures. See, for example, U.S. Pat. Nos. 2,765,289; 2,749,311;
2,760,933; 2,850,453; 2,910,439; 3,663,561; and 3,840,549.
[0027] Rust or corrosion inhibitors are another type of inhibitor
additive for use in embodiments of the present disclosure. Such
materials include monocarboxylic acids and polycarboxylic acids.
Examples of suitable monocarboxylic acids are octanoic acid,
decanoic acid and dodecanoic acid. Suitable polycarboxylic acids
include dimer and trimer acids such as are produced from such acids
as tall oil fatty acids, oleic acid, linoleic acid, or the like.
Another useful type of rust inhibitor may comprise alkenyl succinic
acid and alkenyl succinic anhydride corrosion inhibitors such as,
for example, tetrapropenylsuccinic acid, tetrapropenylsuccinic
anhydride, tetradecenylsuccinic acid, tetradecenylsuccinic
anhydride, hexadecenylsuccinic acid, hexadecenylsuccinic anhydride,
and the like. Also useful are the half esters of alkenyl succinic
acids having 8 to 24 carbon atoms in the alkenyl group with
alcohols such as the polyglycols. Other suitable rust or corrosion
inhibitors include ether amines; acid phosphates; amines;
polyethoxylated compounds such as ethoxylated amines, ethoxylated
phenols, and ethoxylated alcohols; imidazolines; aminosuccinic
acids or derivatives thereof, and the like. Materials of these
types are available as articles of commerce. Mixtures of such rust
or corrosion inhibitors can be used. The amount of corrosion
inhibitor in the transmission fluid formulations described herein
may range from about 0.01 to about 2.0 wt % based on the total
weight of the formulation.
Demulsifiers
[0028] A small amount of a demulsifying component may be used. A
preferred demulsifying component is described in EP 330,522. Such
demulsifying component may be obtained by reacting an alkylene
oxide with an adduct obtained by reacting a bis-epoxide with a
polyhydric alcohol. The demulsifier should be used at a level not
exceeding 0.1 mass % active ingredient. A treat rate of 0.001 to
0.05 mass % active ingredient is convenient.
Pour Point Depressants
[0029] Pour point depressants, otherwise known as lube oil flow
improvers, lower the minimum temperature at which the fluid will
flow or can be poured. Such additives are well known. Typical of
those additives which improve the low temperature fluidity of the
fluid are C.sub.8 to C.sub.18 dialkyl fumarate/vinyl acetate
copolymers, polyalkylmethacrylates, polystyrenesuccinate esters,
and the like.
Viscosity Modifiers
[0030] Viscosity modifiers (VM) function to impart high and low
temperature operability to a lubricating oil. The VM used may have
that sole function, or may be multifunctional.
[0031] Multifunctional viscosity modifiers that also function as
dispersants are also known. Suitable viscosity modifiers are
polyisobutylene, copolymers of ethylene and propylene and higher
alpha-olefins, polymethacrylates, polyalkylmethacrylates,
methacrylate copolymers, copolymers of an unsaturated dicarboxylic
acid and a vinyl compound, inter polymers of styrene and acrylic
esters, and partially hydrogenated copolymers of styrene/isoprene,
styrene/butadiene, and isoprene/butadiene, as well as the partially
hydrogenated homopolymers of butadiene and isoprene and
isoprene/divinylbenzene.
[0032] The additives are typically blended into the base oil in an
amount that enables that additive to provide its desired function.
Representative effective amounts of additives, when used in
lubricant formulations, are listed in Table 1 below. All the values
listed are stated as weight percent active ingredient. These values
are provided merely as exemplary ranges, and are not intended to
limit the embodiments in any way.
TABLE-US-00001 TABLE 1 Wt. % Wt. % Component (Broad) (Typical)
Dispersant 0.5-10.0 1.0-5.0 Metal detergents 0.1-15.0 0.2-2.0
Corrosion Inhibitor 0-5.0 0-2.0 Anti-wear/extreme pressure 0.01-1.0
0.1-0.6 agents Metal-free amine-containing 0.01-1.0 0.1-0.6
friction modifier Antifoaming agent 0-5.0 0.001-0.15 Supplemental
friction modifiers 0-2.0 0.1-1.0 Pour point depressant 0.01-5.0
0.01-1.5 Viscosity modifier 0.01-20.00 0.25-10.0 Base oil Balance
Balance Total 100 100
[0033] The additives may be added directly to the lubricating oil
composition. In one embodiment, however, they are diluted with a
substantially inert, normally liquid organic diluent such as
mineral oil, synthetic oil, naphtha, alkylated (e.g. C.sub.10 to
C.sub.13 alkyl) benzene, toluene or xylene to form an additive
concentrate.
[0034] The following example is given for the purpose of
exemplifying aspects of the embodiments and is not intended to
limit the embodiments in any way.
EXAMPLE 1
[0035] Boundary friction coefficients were measured using a PCS
Instruments High Frequency Reciprocating Rig (HFRR). Friction
coefficients were measured at 130.degree. C. between a SAE 52100
metal ball and either a SAE 52100 metal disk or a 1 cm by 1 cm
piece of plastic slideway material. The ball was oscillated across
the materials at a frequency of 20 Hz over a 1 mm path, with an
applied load of 4.0 N.
[0036] All fluids in Table I were blended into a Group II base oil
with a 100.degree. C. kinematic viscosity of .about.4.0 cSt. The
friction modifiers, anti-wear/extreme pressure agents and
detergents were added to the base oil at a concentration of 0.40
weight percent. The dispersants were added to the base oil at a
concentration of 3.0 weight percent.
[0037] Table I shows the friction data for a series of fluids
containing 1) a friction modifier, 2) an anti-wear/extreme pressure
agent 3) a detergent and 4) a dispersant. The friction modifiers
used in these fluids include: a metal-free, amine-containing
friction modifier (UNAMINE-O), a metal-free, amine-free friction
modifier (glycerol monooleate--GMO) and a metal-containing friction
modifier (molybdenum dithiocarbamate--MoDTC). The anti-wear/extreme
pressure agents used in these fluids include: a metal and
sulfur-free phosphorus compound (dimethyloctylphosphonate--DMOP), a
metal and phosphorus-free sulfur compound (thiadiazole) and a
metal, sulfur and phosphorus containing anti-wear agent (zinc
dithiodiphosphate--ZDDP). The detergents used in these fluids
include: a calcium overbased sulfonate, a calcium overbased phenate
and a calcium overbased sulfonate. The dispersants used in these
fluids include: a succinimide dispersant, a Mannich dispersant and
a functionalized olefin copolymer.
[0038] Table I shows the 130.degree. C. boundary friction
coefficients for all fluids measured on metal and on plastic. In
order to determine the effect of each additive on friction a
standard statistical technique is used in which the "grand average"
of the friction coefficients for each additive is determined. For
example, in Table I, the first ten fluids contain UNAMINE O (U-O).
The average friction coefficient on metal for these first ten
fluids is 0.115 and the average friction coefficient on plastic is
0.069. Fluids 11 through 22 contain glycerol monooleate (GMO) and
the average friction coefficient on metal for these fluids is 0.115
and the average friction coefficient on plastic is 0.091. Fluids 23
through 34 contain molybdenum dithiocarbamate (Mo-DTC) and the
average friction coefficient on metal for these fluids is 0.122 and
the average friction coefficient on plastic is 0.113. The "grand
averages" for each additive on metal and plastic are shown in Table
II.
TABLE-US-00002 TABLE I Boundary Friction Coefficients Measured on
Metal and Plastic Anti- Friction Friction Friction wear/EP
Coefficient Coefficient Sample No. Modifier Agent Detergent
Dispersant On steel On plastic 1 U-O DMOP Sulfonate OCP 0.113 0.069
2 U-O DMOP Salicylate Mannich 0.114 0.063 3 U-O DMOP Phenate
Succinimide 0.106 0.077 4 U-O TDZ Phenate OCP 0.119 0.057 5 U-O TDZ
Sulfonate Mannich 0.127 0.065 6 U-O TDZ Salicylate Succinimide
0.123 0.060 7 U-O ZDDP Salicylate OCP 0.121 0.074 8 U-O ZDDP
Phenate Mannich 0.095 0.072 9 U-O ZDDP Phenate Succinimide 0.117
0.063 10 U-O ZDDP Sulfonate Succinimide 0.115 0.091 11 GMO DMOP
Salicylate OCP 0.128 0.056 12 GMO DMOP Sulfonate Mannich 0.125
0.089 13 GMO DMOP Phenate Succinimide 0.113 0.091 14 GMO DMOP
Salicylate Succinimide 0.132 0.093 15 GMO TDZ Sulfonate OCP 0.125
0.140 16 GMO TDZ Salicylate Mannich 0.120 0.090 17 GMO TDZ Phenate
Succinimide 0.127 0.082 18 GMO ZDDP Phenate OCP 0.098 0.090 19 GMO
ZDDP Phenate Mannich 0.120 0.067 20 GMO ZDDP Salicylate Mannich
0.101 0.079 21 GMO ZDDP Sulfonate Succinimide 0.099 0.122 22 GMO
ZDDP Salicylate Succinimide 0.111 0.091 23 MoDTC DMOP Phenate OCP
0.103 0.072 24 MoDTC DMOP Phenate Mannich 0.111 0.091 25 MoDTC DMOP
Salicylate Mannich 0.107 0.089 26 MoDTC DMOP Salicylate Succinimide
0.151 0.080 27 MoDTC TDZ Salicylate OCP 0.118 0.161 28 MoDTC TDZ
Sulfonate OCP 0.118 0.109 29 MoDTC TDZ Phenate Mannich 0.129 0.104
30 MoDTC TDZ Phenate Succinimide 0.146 0.095 31 MoDTC ZDDP
Sulfonate OCP 0.112 0.117 32 MoDTC ZDDP Sulfonate Mannich 0.097
0.129 33 MoDTC ZDDP Salicylate Mannich 0.134 0.162 34 MoDTC ZDDP
Phenate Succinimide 0.143 0.145
TABLE-US-00003 TABLE 2 Grand Average Friction Coefficients For Each
Component Friction Friction Coefficient on Coefficient on Component
Steel Plastic UNAMINE-O 0.115 0.069 GMO 0.115 0.091 MoDTC 0.122
0.113 DMOP 0.119 0.079 Thiadiazole 0.125 0.096 ZDDP 0.111 0.100
Calcium sulfonate 0.115 0.103 Calcium phenate 0.116 0.085 Calcium
salicylate 0.122 0.092 Functionalized OCP 0.116 0.094 Succinimide
0.124 0.091 Mannich 0.114 0.092
[0039] Table II shows that on metal the friction coefficients for
all the friction modifiers are within 6% of one another
(100*(0.122-0.115)/0.122). However, on plastic, the average
friction coefficient for fluids containing GMO is 19% lower
(100*(0.113-0.091)/0.113) than the average friction coefficient for
fluids containing MoDTC. In addition, the average friction
coefficient for fluids containing U-O is 39% lower
(100*(0.113-0.069)/0.113) than the average friction coefficient for
fluids containing MoDTC.
[0040] Table II also shows that for antiwear agents the average
friction coefficients on metal for fluids containing thiadiazole
(0.125) or DMOP (0.119) are greater than the average friction
coefficient for fluids containing ZDDP (0.111). However, on plastic
the average friction coefficient for fluids containing DMOP is 21%
lower (100*(0.100-0.079)/0.100) than the average friction
coefficient for fluids containing ZDDP. In addition, on plastic the
average friction coefficient for fluids containing DMOP is 18%
lower (100*(0.096-0.079)/0.096) than the average friction
coefficient for fluids containing thiadiazole.
EXAMPLE 2
[0041] In another series of tests, boundary friction coefficients
were measured as in Example 1 at 130.degree. C. between a SAE 52100
metal ball and a 1 cm by 1 cm piece of plastic slideway material.
In test fluid contained a base oil having only 0.2 weight percent
of each of the friction modifiers or anti-wear agents listed in
example 1. The results are given in the following Table 3.
TABLE-US-00004 TABLE 3 Weight percent 130.degree. C. Friction in
base oil Additive Coefficient on plastic 0.20 MoDTC 0.268 0.20 ZDDP
0.202 0.20 Thiadiazole 0.142 0.20 GMO 0.106 0.20 DMOP 0.094 0.20
U--O 0.072
[0042] According to the foregoing examples, the following
observations may be articulated: [0043] 1) metal-free friction
modifiers (thiadiazole, GMO, DMOP and U-O) reduce friction on
plastic better than metal-containing friction modifiers. [0044] 2)
amine-containing metal-free friction modifiers (U-O) reduce
friction better than amine-free metal-free friction modifiers.
[0045] 3) metal- and sulfur-free phosphorus compounds (DMOP) reduce
friction on plastic better than metal-containing phosphorus/sulfur
compounds and metal-free sulfur compounds.
[0046] It is expected that a lubricant composition containing an
amine-containing metal-free friction modifier and a metal- and
sulfur-free phosphorus compound will provide superior boundary
friction characteristics on plastic materials.
[0047] At numerous places throughout this specification, reference
has been made to a number of U.S. Patents. All such cited documents
are expressly incorporated in full into this disclosure as if fully
set forth herein.
[0048] The foregoing embodiments are susceptible to considerable
variation in its practice. Accordingly, the embodiments are not
intended to be limited to the specific exemplifications set forth
hereinabove. Rather, the foregoing embodiments are within the
spirit and scope of the appended claims, including the equivalents
thereof available as a matter of law.
[0049] The patentees do not intend to dedicate any disclosed
embodiments to the public, and to the extent any disclosed
modifications or alterations may not literally fall within the
scope of the claims, they are considered to be part hereof under
the doctrine of equivalents.
* * * * *