U.S. patent application number 15/350482 was filed with the patent office on 2017-03-02 for stabilized blends containing friction modifiers.
The applicant listed for this patent is The Lubrizol Corporation. Invention is credited to James D. Burrington, Ewan E. Delbridge, John J. Mullay.
Application Number | 20170058230 15/350482 |
Document ID | / |
Family ID | 43903816 |
Filed Date | 2017-03-02 |
United States Patent
Application |
20170058230 |
Kind Code |
A1 |
Burrington; James D. ; et
al. |
March 2, 2017 |
STABILIZED BLENDS CONTAINING FRICTION MODIFIERS
Abstract
The present invention relates to functional fluid compositions
containing friction modifiers, and specifically stable compositions
containing friction modifiers with limited solubility in and/or
limited compatibility with the functional fluids with which they
are used. In particular the present invention deals with functional
fluids used in internal combustion engines, such as engine oils,
and friction modifiers that contain one or more amide functional
groups, where the friction modifier is present in the functional
fluid composition at levels that would otherwise cause the
composition to be unstable and/or hazy.
Inventors: |
Burrington; James D.; (Gates
Mills, OH) ; Mullay; John J.; (Mentor, OH) ;
Delbridge; Ewan E.; (Concord Township, OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The Lubrizol Corporation |
Wickliffe |
OH |
US |
|
|
Family ID: |
43903816 |
Appl. No.: |
15/350482 |
Filed: |
November 14, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13512395 |
Jul 17, 2012 |
9528067 |
|
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PCT/US2010/056916 |
Nov 17, 2010 |
|
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15350482 |
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61264875 |
Nov 30, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10N 2080/00 20130101;
C10M 2223/043 20130101; C10M 141/10 20130101; C10M 2223/04
20130101; C10M 141/06 20130101; C10M 169/04 20130101; C10M 141/08
20130101; C10M 2223/047 20130101; C10M 2215/08 20130101; C10M
2215/082 20130101; C10M 163/00 20130101; C10N 2030/52 20200501;
C10N 2040/25 20130101; C10N 2060/14 20130101; C10N 2030/06
20130101; C10M 2219/046 20130101; C10M 2219/066 20130101; C10M
2215/28 20130101; C10M 2207/028 20130101; C10M 2219/044 20130101;
C10M 2215/224 20130101; C10N 2020/06 20130101; C10N 2030/66
20200501; C10M 2219/046 20130101; C10N 2010/04 20130101; C10M
2219/046 20130101; C10N 2010/04 20130101 |
International
Class: |
C10M 169/04 20060101
C10M169/04; C10M 141/10 20060101 C10M141/10; C10M 141/06 20060101
C10M141/06; C10M 141/08 20060101 C10M141/08 |
Claims
1. A composition comprising: (a) a medium comprising a solvent, a
functional fluid, or combinations thereof; (b) from about 1.0 to
about 5 percent by weight of a friction modifier component
comprising oleyl amide, stearyl amide, or combinations thereof and
is not fully soluble in the medium; (c) from about 1 to about 8
percent by weight of a stabilizing component that is soluble in (a)
and that interacts with (b) such that (b)'s solubility in (a) is
improved; wherein components (b) and (c) are present in component
(a) in the form of dispersed particles having an average diameter
of less than 10 microns.
2. The composition of claim 1 wherein component (c), the
stabilizing component, comprises: (i) an overbased detergent with a
metal to substrate ratio of greater than 3:1 wherein the overbased
detergent is optionally borated; (ii) an alkyl imidazoline; (iii) a
hydrocarbyl phosphoric acid or acid ester, a hydrocarbyl
thiophosphoric acid or acid ester, a hydrocarbyl dithiophosphoric
acid or acid ester, an amine salt of one or more of these acids and
acids esters, or combinations thereof; (iv) an alkylbenzene
sulfonate or derivatives thereof; or combinations thereof.
3. The composition of claim 2 wherein component (c), the
stabilizing component, comprises a compound represented by the
formula: ##STR00007## or a slated version thereof, wherein: X.sup.1
is an oxygen atom, a sulfur atom, a hydrocarbylene group, or
--N(R.sup.2)--; R.sup.1 is a hydrocarbylene group; X.sup.2 is an
oxygen atom or a sulfur atom or a hydrocarbyl group; X.sup.3 is
.dbd.C<, .dbd.P(OR.sup.2)<, or .dbd.S(O)<; Y is --R.sup.2,
or --OR.sup.2; each R.sup.2 is independently a hydrocarbyl group or
--H; and each n is independently 0 or 1.
4. The composition of claim 2 wherein (c), the stabilizing agent,
comprises: (i) an overbased phenate detergent with a metal to
substrate ratio of greater than 3:1; (ii) an alkyl imidazoline;
(iii) a hydrocarbyl dithiophosphoric acid, (iv) a amine salt of a
phosphoric acid ester; (v) an alkylbenzenesulfonate or derivatives
thereof, or combinations thereof.
5. The composition of claim 2 wherein the overbased detergent is an
overbased phenate with a TBN of at least 200.
6. The composition of claim 2 wherein the alkyl imidazoline is
derived from a fatty acid and an alkylene polyamine.
7. The composition of claim 1 wherein the turbidity of the overall
composition is improved, as defined by a lower JTU and/or NTU value
compared to the same composition that does not contain (c), the
stabilizing component.
8. A process of preparing a clear and stable composition
comprising: (a) a medium comprising a solvent, a functional fluid,
or combinations thereof; (b) from about 1.0 to about 5 percent by
weight of a friction modifier component comprising oleyl amide,
stearyl amide, or combinations thereof and is not fully soluble in
the medium; and (c) from about 1 to about 8 percent by weight of a
stabilizing component that is soluble in (a) and that interacts
with (b) such that (b)'s solubility in (a) is improved; said method
comprising the steps of: I. adding components (b) and (c) to
component (a); and II. mixing the components so that particles of
components (b) and (c) have an average diameter of less than 10
microns.
9. The process of claim 8, wherein component (c), the stabilizing
component, comprises: (i) an overbased detergent with a metal to
substrate ratio of greater than 3:1 wherein the overbased detergent
is optionally borated; (ii) an alkyl imidazoline; (iii) a
hydrocarbyl phosphoric acid or acid ester, a hydrocarbyl
thiophosphoric acid or acid ester, a hydrocarbyl dithiophosphoric
acid or acid ester, an amine salt of one or more of these acids and
acids esters, or combinations thereof; (iv) an alkylbenzene
sulfonate or derivatives thereof; or combinations thereof.
10. The process of claim 9, wherein component (c), the stabilizing
component, comprises a compound represented by the formula:
##STR00008## or a slated version thereof, wherein: X.sup.1 is an
oxygen atom, a sulfur atom, a hydrocarbylene group, or
--N(R.sup.2)--; R.sup.1 is a hydrocarbylene group; X.sup.2 is an
oxygen atom or a sulfur atom or a hydrocarbyl group; X.sup.3 is
.dbd.C<, .dbd.P(OR.sup.2)<, or .dbd.S(O)<; Y is --R.sup.2,
or --OR.sup.2; each R.sup.2 is independently a hydrocarbyl group or
--H; and each n is independently 0 or 1.
11. The process of claim 9, wherein (c), the stabilizing agent,
comprises: (i) an overbased phenate detergent with a metal to
substrate ratio of greater than 3:1; (ii) an alkyl imidazoline;
(iii) a hydrocarbyl dithiophosphoric acid, (iv) a amine salt of a
phosphoric acid ester; (v) an alkylbenzenesulfonate or derivatives
thereof, or combinations thereof.
12. The process of claim 9, wherein the overbased detergent is an
overbased phenate with a TBN of at least 200.
13. The process of claim 9, wherein the alkyl imidazoline is
derived from a fatty acid and an alkylene polyamine.
14. The process of claim 8, wherein the turbidity of the overall
composition is improved, as defined by a lower JTU and/or NTU value
compared to the same composition that does not contain (c), the
stabilizing component.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of U.S.
application Ser. No. 13/512,395 filed on Jul. 17, 2012, which
claims priority to PCT Application Serial No. PCT/US2010/056916
filed on Nov. 17, 2010, which claims the benefit of Provisional
Application Ser. No. 61/264,875 filed on Nov. 30, 2009. These
applications are incorporated in their entirety herein by
reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to functional fluid
compositions containing friction modifiers, and specifically stable
compositions containing friction modifiers with limited solubility
in and/or limited compatibility with the functional fluids with
which they are used.
[0003] Friction modifiers and their importance to various types of
functional fluids are known. However, many friction modifiers may
only be used in limited ways due to solubility and/or compatibility
issues with the functional fluids in which they are used. Many
friction modifiers, and specifically those derived from
hydroxy-carboxylic acids, have limited solubility in functional
fluids, such as engine oils and gear oils. These friction
modifiers, when used at levels above their solubility and/or
compatibility limits, may fall out of the functional fluid
composition over time and/or cause the composition to appear hazy
or cloudy.
[0004] These are serious issues in the manufacturing and blending
processes of the fluids as well as in the field. For example, a
functional fluid additive manufacturer would sell a homogeneous
additive package of performance chemicals, which may then be added
to a base oil to give a final lubricant, which in turn is sold in
tanks, drums, cans and plastic containers for final delivery of the
lubricant to the equipment to be lubricated. To maintain assurance
of performance of the final lubricant, or any other functional
fluid, in the equipment in which it is used, the concentrate and
the lubricant must remain homogeneous throughout these steps. In
other words, all of the additives present must be compatible with
each of the various materials it comes into contact with and/or
finds itself, from the additive package to the concentrate to the
final fluid. This stringent standard greatly limits the choices of
and available treatment levels for many additives, including the
friction modifiers discussed herein. These friction modifiers could
provide improved performance to a functional fluid but not widely
used and/or are not used at the optimal level because the additive
does not meet the solubility and/or compatibility requirements
discussed above.
[0005] In the field, functional fluid compositions that drop out
one or more components over time may not perform properly unless
they are well-mixed before use, or may be removed by filters
associated with the equipment in which the functional fluid is
used. The haziness and/or cloudiness of a functional fluid, which
may be measured as the fluid's turbidity, is often seen as a sign
the composition is not stable, or may be in an early stage of
separation and/or component drop out. Such conditions are not
desired in functional fluid compositions, for both performance and
aesthetic related reasons. This reality has created constraints on
the use of various friction modifiers, such as effective maximum
treat rates.
[0006] Without these solubility and/or compatibility limitations on
the use of these friction modifiers, greater performance and
equipment protection might be achievable, including for example
extended life of a lubricant or a lubricated piece of equipment
such as engines, automatic transmissions, gear assemblies and the
like. Improved fuel economy and viscosity stability might be
achievable as well. Greater performance may even be achievable with
lesser amounts of chemical as well as greater amounts, depending on
the selection of the more effective, but otherwise not suitable
chemicals from a compatibility or solubility standpoint when
delivered in a conventional manner.
[0007] There is a need for functional fluid compositions that
contain higher amounts of friction modifiers while still remaining
stable and/or clear. There is particularly a need for functional
fluid compositions, such as engine oil compositions, that contain
friction modifiers derived from a hydroxy-carboxylic acid, at
levels that would otherwise cause the composition to be unstable
and/or hazy, as described above. The compositions and methods of
the present invention overcome these constraints and thus allow the
use of these friction modifiers at levels not otherwise possible
while still maintaining the stability and/or clarity of the
functional fluid composition.
SUMMARY OF THE INVENTION
[0008] Functional fluid compositions have been discovered that may
contain high amounts of friction modifiers, and particularly
friction modifiers with limited solubility in and/or compatibility
with the functional fluid compositions in which they are used,
allowing for the use of higher amounts of such friction modifiers
in these functional fluid compositions, while maintaining the
stability, clarity, and/or compatibility of the overall
composition.
[0009] The present invention provides a composition that includes:
(a) a medium, which may include a solvent, a functional fluid, or
combinations thereof; and (b) a friction modifier component that is
not fully soluble in the medium; and (c) a stabilizing component
that is soluble in (a) and that interacts with (b) such that (b)'s
solubility in (a) is improved, or perhaps more accurately, (b)'s
solubility in the combination of (a) and (b) is improved over (b)'s
solubility in (a). Components (b) and (c) may be present in
component (a) in the form of dispersed particles having an average
diameter of less than 10 microns.
[0010] In some embodiments component (b), the friction modifier,
includes a compound containing one or more amide functional groups
and component (c), the stabilizing component, includes: (i) an
overbased detergent with a metal to substrate ratio of greater than
3:1, including borated versions; (ii) an alkyl imidazoline; (iii) a
hydrocarbyl phosphoric acid or acid ester, a hydrocarbyl
thiophosphoric acid or acid ester, a hydrocarbyl dithiophosphoric
acid or acid ester, an amine salt of one or more of these acids and
acids esters, or combinations thereof; (iv) an alkylbenzene
sulfonate or derivatives thereof; or combinations thereof
[0011] In some embodiments the compositions of the present
invention result in an improvement in the turbidity of the
composition, as defined by a lower Jackson Turbidity Unit (JTU)
and/or Nephelometric Turbidity Unit (NTU) value compared to the
same composition that does not contain (c), the stabilizing
component. In some embodiments the compositions of the present
invention have a maximum JTU and/or NTU value of 100.
[0012] The present invention also provides for a process of
preparing a clear and stable composition, as described herein, said
method including the steps of: (I) adding components (b) and (c) to
component (a); and (II) mixing the components so that particles of
components (b) and (c) have an average diameter of less than 10
microns.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Various preferred features and embodiments will be described
below by way of non-limiting illustration.
[0014] The present invention provides compositions and methods that
allow for the use of certain friction modifiers in functional fluid
compositions that could not otherwise be used, and/or could not be
used at the levels allowed for by the present invention, without
resulting in unstable, unclear, and/or hazy compositions.
[0015] The types of functional fluids in and with which the
compositions and methods of the present invention may be used can
include: gear oils, transmission oils, hydraulic fluids, engine
oils, two cycle oils, metalworking fluid, fuels and the like. In
one embodiment the functional fluid is engine oil. In another
embodiment the functional fluid is gear oil. In another embodiment
the functional fluid is a transmission fluid. In another embodiment
the functional fluid is a hydraulic fluid. In another embodiment
the functional fluid is a fuel.
[0016] In some embodiments the present invention does not include
the use of a delivery device, for example a device that acts to
contain the friction modifier and contact it with the functional
fluid with which it is to be added. In some embodiments the present
invention does not included the use of either a gel composition or
a solid composition, where such compositions slow release one or
more components into a functional fluid. Rather the present
invention provides a means for incorporating friction modifiers
into functional fluids, by use of a combination of components,
which result in a functional fluid with the high level of friction
modifier while still being stable, clear and/or non-hazy.
[0017] In some embodiments the present invention provides a
composition that is more stable, clearer, and/or less hazy than a
composition that is identical except for it missing one or more
components. In some embodiments the missing component is the
stabilizing component. In other embodiments the compositions of the
present invention have a lower turbidity compared to compositions
that are identical except for them missing the stabilizing
component of the present invention. In some of these embodiments,
the compositions' turbidity is expressed as a JTU and/or NTU value.
In other embodiments the compositions of the present invention have
a maximum JTU and/or NTU value of 100, of 90 or even of 80.
[0018] JTU and NTU values may be measured US EPA method 180.1. JTU
and NTU values may also be measured without any further dilution in
Jackson Turbidity Units (JTU's) by using a Monitek Model 151
Turbidimeter.
The Medium
[0019] The compositions of the present invention include a medium.
The medium may be a solvent, a functional fluid, an additive
concentrate, or combinations thereof.
[0020] Suitable solvents include aliphatic hydrocarbons, aromatic
hydrocarbons, oxygen containing compositions, or mixtures thereof.
The oxygen containing composition can include an alcohol, a ketone,
an ester of a carboxylic acid, a glycol and/or a polyglycol, or a
mixture thereof. Suitable solvents also include oils of lubricating
viscosity, naphtha, toluene, xylene, or combinations thereof. The
oil of lubricating viscosity can comprise natural oils, synthetic
oils, or mixtures thereof. The oil of lubricating viscosity can be
an API (American Petroleum Institute) Group II, III, IV, V base oil
or mixture thereof. Examples of commercially available aliphatic
hydrocarbon solvents or diluents, to include oils of lubricating
viscosity, are Pilot.TM. 140 and Pilot.TM. 299 and Pilot.TM. 900
available from Petrochem Carless, Petro-Canada.TM. 100N,
Nexbase.TM., Yubase.TM., and 4 to 6 cSt poly(alpha-olefins).
[0021] Suitable functional fluids include any of the functional
fluids listed above, including mixtures of such fluids. In many
embodiments the functional fluids, or other materials used as the
medium, contain additional additives in addition to components (b)
and (c) described in detail below. These additional additives are
described in greater detail below.
[0022] In one embodiment of the invention the medium and/or the
overall composition is substantially free of or free of at least
one member selected from the group consisting of sulphur,
phosphorus, sulfated ash, and combinations thereof, and in other
embodiments the fuel composition contains less than 20 ppm, less
than 15 ppm, less than 10 ppm, or less than 1 ppm of at least one
member selected from the group consisting of sulphur, phosphorus,
sulfated ash, and combinations thereof.
[0023] In one embodiment, the medium and the stabilizing component
may be similar materials. That is a material of the same type may
perform the functions of both components. For example when the
invention is in the form of a concentrate the medium present may
act as a stabilizing component and vice versa. This concentrate may
then be added to a functional fluid as a top treat and/or additive
package, resulting in a stable and homogeneous functional fluid
which would otherwise be cloudy or incompatible in the absence of
stabilizer component/medium material.
The Friction Modifier
[0024] The compositions of the present invention include a friction
modifier component. The friction modifier component may include a
least one friction modifier that is not fully soluble and/or
compatible in the medium and/or functional fluid in which it is to
be used. By not fully soluble and/or compatible, it is meant that
the friction modifier does not stay dissolved and/or suspended in
the fluid to which it is added, causes the fluid to appear hazy
and/or cloudy, have sediments, or any combination thereof. In some
embodiments, the friction modifier causes the fluid in which it is
used to have an NTU and/or JTU value above 80, 90 or even 100. In
some embodiments this fluid is a functional fluid composition such
as a finished lubricant or an additive concentrate.
[0025] In some embodiments the friction modifier of the present
invention is soluble and/or compatible with a fluid at low
concentrations, but becomes less than soluble and/or compatible at
higher concentrations. In some embodiments friction modifiers
suitable for use in the present invention are not fully soluble
and/or compatible, as defined above, when present in a fluid at
concentrations of or more than 0.1, 0.15, 0.2, 0.3, 0.5, or 1.0
percent by weight.
[0026] In some embodiments the friction modifier of the present
invention comprises a compound containing one or more amide
functional groups. Suitable friction modifiers include compounds
represented by Formula (I):
##STR00001##
wherein: X.sup.4 is an oxygen atom or a sulfur atom; and each
R.sup.2 and R.sup.3 is independently a hydrogen or a hydrocarbyl
group. Examples of suitable friction modifiers include oleyl amide,
stearyl amide, or combinations thereof.
[0027] Fatty acid amides have been discussed in detail in U.S. Pat.
No. 4,280,916. Suitable amides are C.sub.8-C.sub.24 aliphatic
monocarboxylic amides and are well known. Reacting the fatty acid
based compound with ammonia or an amine produces the fatty amide.
The fatty acids and amides derived there from may be either
saturated or unsaturated. Important fatty acids include lauric acid
(C.sub.12), palmitic acid (C.sub.16), and steric acid (C.sub.18).
Other important unsaturated fatty acids include oleic, linoleic and
linolenic acids, all of which are C.sub.18. In one embodiment, the
fatty amides of the instant invention are those derived from the
C.sub.18 unsaturated fatty acids.
[0028] The fatty amines and the diethoxylated long chain amines
such as N,N-bis-(2-hydroxyethyl)-tallowamine themselves are
generally useful as friction modifier components of this invention.
Both types of amines are commercially available. Fatty amines and
ethoxylated fatty amines are described in greater detail in U.S.
Pat. No. 4,741,848.
[0029] The friction modifier may be present in the compositions of
the present invention at levels of at least 0.05, 0.1, 0.15, 0.2,
0.3, 0.5 or even 1.0 percent by weight. The friction modifier may
be present at less than 10, 7.5, 5, or even 4 or 3 percent by
weight.
[0030] The compositions of the present invention, and specifically
the friction modifier component, may optionally include one or more
additional friction modifiers. These additional friction modifiers
may or may not have the solubility and/or compatibility issues of
the friction modifiers described above. These additional friction
modifiers may include esters of polyols such as glycerol
monooleates, as well as there borated derivatives; fatty
phosphites; borated fatty epoxides; sulfurized olefins; compounds
derived from a hydroxy-carboxylic acid such as oleyl tartrimide,
stearyl tartrimide, and 2-ethylhexyl tartrate; and mixtures
thereof.
[0031] Esters of polyols include fatty acid esters of glycerol.
These can be prepared by a variety of methods well known in the
art. Many of these esters, such as glycerol monooleate and glycerol
mono-tallowate, are manufactured on a commercial scale. The esters
useful for this invention are oil-soluble and are preferably
prepared from C.sub.8 to C.sub.22 fatty acids or mixtures thereof
such as are found in natural products. The fatty acid may be
saturated or unsaturated. Certain compounds found in acids from
natural sources may include licanic acid which contains one keto
group. Useful C.sub.8 to C.sub.22 fatty acids are those of the
formula R--COOH wherein R is alkyl or alkenyl.
[0032] The fatty acid monoester of glycerol is useful. Mixtures of
mono and diesters may be used. Mixtures of mono- and diester can
contain at least about 40% of the monoester. Mixtures of mono- and
diesters of glycerol containing from about 40% to about 60% by
weight of the monoester can be used. For example, commercial
glycerol monooleate containing a mixture of from 45% to 55% by
weight monoester and from 55% to 45% diester can be used.
[0033] Useful fatty acids for making these fatty acid esters
include oleic, stearic, isostearic, palmitic, myristic,
palmitoleic, linoleic, lauric, linolenic, and eleostearic, and the
acids from the natural products tallow, palm oil, olive oil, peanut
oil.
[0034] Friction modifiers derived from a hydroxy-carboxylic acid
may be formed by the reaction of the acid with an alcohol and/or an
amine. Suitable hydroxy-carboxylic acid include those represented
by Formula II:
##STR00002##
wherein: a and b may be independently integers of 1 to 5, or 1 to
2; X may be an aliphatic or alicyclic group, or an aliphatic or
alicyclic group containing an oxygen atom in the carbon chain, or a
substituted group of the foregoing types, said group containing up
to 6 carbon atoms and having a+b available points of attachment;
each Y may be independently --O--, >NH, or >NR.sup.3 or two
Y's together representing the nitrogen of an imide structure
R.sup.1--N< formed between two carbonyl groups; and each R.sup.1
and R.sup.3 may be independently hydrogen or a hydrocarbyl group,
provided that at least one R.sup.1 and R.sup.3 group may be a
hydrocarbyl group; each R.sup.2 may be independently hydrogen, a
hydrocarbyl group or an acyl group, further provided that at least
one --OR.sup.2 group is located on a carbon atom within X that is
.alpha. or .beta. to at least one of the --C(O)--Y--R.sup.1
groups.
[0035] In one embodiment the acid is represented by Formula
III.
##STR00003##
wherein each R.sup.4 is independently H or a hydrocarbyl group, or
wherein the R.sup.4 groups together form a ring. In one embodiment
the friction modifier is borated. In another embodiment the
friction modifier is not borated.
[0036] In any of the embodiments above, the hydroxy-carboxylic acid
may be tartaric acid, citric acid, or combinations thereof, and may
also be a reactive equivalent of such acids (including esters, acid
halides, or anhydrides). The resulting friction modifiers may
include imide, di-ester, di-amide, or ester-amide derivatives of
tartaric acid, citric acid, or mixtures thereof. In one embodiment
the derivative of hydroxycarboxylic acid includes an imide, a
di-ester, a di-amide, or an ester-amide derivative of tartaric
acid.
[0037] The amines used in the preparation of the friction modifier
may have the formula RR'NH wherein R and R' each independently
represent H, a hydrocarbon-based radical of 1 or 8 to 30 or 150
carbon atoms, that is, 1 to 150 or 8 to 30 or 1 to 30 or 8 to 150
atoms. Amines having a range of carbon atoms with a lower limit of
2, 3, 4, 6, 10, or 12 carbon atoms and an upper limit of 120, 80,
48, 24, 20, 18, or 16 carbon atoms may also be used. In one
embodiment, each of the groups R and R' has 8 or 6 to 30 or 12
carbon atoms. In one embodiment, the sum of carbon atoms in R and
R' is at least 8. R and R' may be linear or branched. In one
embodiment R and R' are linear and have at leas 12 carbons. In such
embodiments the groups may include some unsaturation.
[0038] The alcohols useful for preparing the friction modifier will
similarly contain 1 or 8 to 30 or 150 carbon atoms. Alcohols having
a range of carbon atoms from a lower limit of 2, 3, 4, 6, 10, or 12
carbon atoms and an upper limit of 120, 80, 48, 24, 20, 18, or 16
carbon atoms may also be used. In certain embodiments the number of
carbon atoms in the alcohol-derived group may be 8 to 24, 10 to 18,
12 to 16, or 13 carbon atoms.
[0039] The alcohols and amines may be linear or branched, and, if
branched, the branching may occur at any point in the chain and the
branching may be of any length. In some embodiments the alcohols
and/or amines used include branched compounds, and in still other
embodiments, the alcohols and amines used are at least 50%, 75% or
even 80% branched.
[0040] In some embodiments, the alcohol and/or amine used includes
branched C.sub.6-18 or C.sub.8-18 alcohols, branched C.sub.12-16
alcohols, 2-ethylhexanol, isotridecyl alcohol, linear C.sub.6-18 or
C.sub.8-18 alcohols, linear C.sub.12-16 alcohols, or combinations
thereof.
[0041] In one embodiment the hydroxy-acid derived friction modifier
can be represented by a compound of Formula IV.
##STR00004##
wherein: n' is 0 to 10; p is 1 to 5; Y and Y' are independently
--O--, >NH, >NR.sup.7, or an imide group formed by the
linking of the Y and Y' groups forming a R.sup.1--N< group
between two >C.dbd.O groups; R.sup.5 and R.sup.6 are
independently hydrocarbyl groups, typically containing 1, 4 or 6 to
150, 30 or 24 carbon atoms; m is 0 or 1, and X is independently
--CH.sub.2--, >CHR.sup.8 or >CR.sup.8R.sup.9,
>CHOR.sup.10, or >C(CO.sub.2R.sup.10).sub.2, --CH.sub.3,
--CH.sub.2R.sup.8 or --CHR.sup.8R.sup.9, --CH.sub.2OR.sup.10, or
--CH(CO.sub.2R.sup.10).sub.2, or mixtures thereof wherein: R.sup.7
is a hydrocarbyl group; R.sup.8 and R.sup.9 are independently
keto-containing groups (such as acyl groups), ester groups or
hydrocarbyl groups; and R.sup.10 is independently hydrogen or a
hydrocarbyl group, typically containing 1 to 150 carbon atoms.
[0042] In some embodiments the compounds represent by Formula IV
have at least one X that is hydroxyl-containing (e.g.,
>CHOR.sup.10, wherein R.sup.10 is hydrogen). When X is
hydroxyl-containing, the compound may be derived from
hydroxy-carboxylic acids such as tartaric acid, citric acid, or
mixtures thereof. In one embodiment the compound is derived from
citric acid and R.sup.5 and R.sup.6 contain at least 6 or 8 carbon
atoms up to 150, or 6 or 8 to 30 or 24 carbon atoms. In one
embodiment the compound is derived from tartaric acid and R.sup.5
and R.sup.6 contain 4 or 6 to 30 or 24 carbon atoms. When X is not
hydroxyl-containing, the compound may be derived from malonic acid,
oxalic acid, chlorophenyl malonic acid, reactive equivalents
thereof such as esters, or mixtures thereof.
[0043] In some embodiments the compositions of the present
invention do not include any of these optional friction modifiers
and in other embodiments, one or more of any of the optional
friction modifiers listed herein are not present in the
compositions of the present invention.
[0044] In other embodiments an additional friction modifier is
present, and that friction modifier is derived from a hydroxy-acid.
In other embodiments the additional friction modifier is oleyl
tartrimide, stearyl tartrimide, 2-ethylhexyl tartrimide, or
combinations thereof.
[0045] The additional friction modifier may be present in the
compositions of the present invention at levels of at least 0.05,
0.1, 0.15, 0.2, 0.3, 0.5 or even 1.0 percent by weight. The
additional friction modifier may be present at less than 10, 7.5,
5, or even 4 or 3 percent by weight.
The Stabilizing Component
[0046] The compositions of the present invention include a
stabilizing component. The stabilizing component of the present
invention is soluble in medium and that interacts with the friction
modifier such that its solubility in the medium and/or overall
composition is improved. This may be accomplished by an association
of the stabilizing component and the friction modifier, resulting
in suspended particles of the associated molecules, which remain
suspended, dispersed and/or dissolved in the medium and/or overall
composition to an extent greater than obtained by the friction
modifier alone.
[0047] The stabilizing component of the present invention is an
additive that, when combined with the friction modifier in the
medium, results in an improvement in the turbidity of the
composition, compared to the same composition that does not contain
the stabilizing component.
[0048] The stabilizing component may include: (i) an overbased
detergent with a metal to substrate ratio of greater than 3:1,
including borated versions thereof; (ii) an alkyl imidazoline;
(iii) a hydrocarbyl phosphoric acid or acid ester, a hydrocarbyl
thiophosphoric acid or acid ester, a hydrocarbyl dithiophosphoric
acid or acid ester, an amine salt of one or more of these acids and
acids esters, or combinations thereof; (iv) an alkylbenzene
sulfonate or derivatives thereof; or combinations thereof.
The Overbased Detergent.
[0049] The stabilizing component may include an overbased
detergent. Suitable detergents have a metal to substrate ratio of
greater than 3:1. Overbased materials, also referred to as
overbased or superbased salts, are generally single phase,
homogeneous Newtonian systems characterized by an amount of excess
metal that which would be necessary for neutralization according to
the stoichiometry of the metal and the particular acidic organic
compound reacted with the metal. The amount of excess metal is
commonly expressed in terms of "substrate to metal ratio" which is
the ratio of the total equivalents of the metal to the equivalents
of the substrate. A more detailed description of the term metal
ratio is provided in "Chemistry and Technology of Lubricants",
Second Edition, Edited by R. M. Mortier and S. T. Orszulik, pages
85 and 86, 1997.
[0050] The basicity of overbased materials is generally expressed
in terms of a total base number (TBN). A TBN is the amount of acid
(perchloric or hydrochloric) needed to neutralize all of the
overbased material's basicity. The amount of acid is expressed as
potassium hydroxide (mg KOH per gram of sample). TBN is determined
by titration of overbased material with 0.1 Normal hydrochloric
acid solution using bromophenol blue as an indicator. The
equivalents of an overbased material are determined by the
following equation: equivalent weight=(56,100/TBN). The overbased
materials of the present invention generally have a total base
number of at least 100 or 200 or 250 or 255 and generally less than
450 or no more than 400.
[0051] Overbased maybe prepared by reacting an acidic material
(typically an inorganic acid or lower carboxylic acid, for example
carbon dioxide) with a mixture comprising an acidic organic
compound, a reaction medium comprising at least one inert, organic
solvent (mineral oil, naphtha, toluene, xylene, etc.) for said
acidic organic material, a stoichiometric excess of a metal base,
and a promoter. Useful acidic organic compounds include carboxylic
acids, sulfonic acids, phosphorus-containing acids, phenols
(including alkylated phenols) or mixtures of two or more thereof.
In some embodiments the acidic organic compounds are sulfonic acids
or phenols. Throughout this specification, any reference to acids,
such as carboxylic or sulfonic acids, is intended to include the
acid-producing derivatives thereof such as anhydrides, lower alkyl
esters, acyl halides, lactones and mixtures thereof, unless
otherwise specifically stated.
[0052] Suitable overbased detergents include overbased calcium
sulfonates, which are derived from sulfonic acids. Suitable acids
include sulfonic and thiosulfonic acids, and salts thereof, and
also include mono or polynuclear aromatic or cycloaliphatic
compounds. The oil-soluble sulfonates can be represented for the
most part by one of the following formulae:
R.sub.2-T-(SO.sub.3.sup.+).sub.a and
R.sub.3--(SO.sub.3.sup.-).sub.b, wherein T is a cyclic nucleus such
as benzene, toluene, naphthalene, anthracene, diphenyl oxide,
diphenyl sulfide, petroleum naphthenes, or combinations thereof;
R.sub.2 is an aliphatic group such as alkyl, alkenyl, alkoxy,
alkoxyalkyl, or combinations thereof; (R.sub.2)+T contains a total
of at least 15 carbon atoms; and R.sub.3 is an aliphatic
hydrocarbyl group containing at least 15 carbon atoms. R.sub.3 may
be an alkyl, alkenyl, alkoxyalkyl, or carboalkoxyalkyl group. In
one embodiment, the sulfonic acids have a substituent (R.sub.2 or
R.sub.3) derived from one of the above-described polyalkenes, and
in some embodiments may be derived from PIB, as described
above.
[0053] The production of sulfonates from detergent manufactured
by-products by reaction with, e.g., SO.sub.3, is well known to
those skilled in the art. See, for example, the article
"Sulfonates" in Kirk-Othmer "Encyclopedia of Chemical Technology",
Second Edition, Vol. 19, pp. 291 et seq. published by John Wiley
& Sons, N.Y. (1969).
[0054] The metal compounds useful in making the basic metal salts
are generally any Group 1 or Group 2 metal compounds. In some
embodiments the metal used is sodium or potassium, or even sodium.
In other embodiments the metals of the metal base include the Group
2a alkaline earth metals such as magnesium, calcium, and barium, as
well as the Group 2b metals such as zinc. In some embodiments the
Group 2 metals are magnesium, calcium, barium, or zinc, and in some
embodiments magnesium or calcium, or even calcium. The metal
compounds may be delivered as metal salts. The anionic portion of
the salt can be hydroxide, oxide, carbonate, borate, and/or
nitrate.
[0055] An acidic material may be used to accomplish the formation
of the overbased detergent. The acidic material may be a liquid
such as formic acid, acetic acid, nitric acid, and/or sulfuric
acid. Acetic acid is particularly useful. Inorganic acidic
materials may also be used such as HCl, SO.sub.2, SO.sub.3,
CO.sub.2, and H.sub.2S. In some embodiments the material used is
CO.sub.2, often used in combination with acetic acid. An acidic gas
may be employed to accomplish the formation of the overbased
detergent, such as carbon dioxide or sulfur dioxide.
[0056] A promoter is a chemical employed to facilitate the
incorporation of metal into the basic metal compositions. A
particularly comprehensive discussion of suitable promoters is
found in U.S. Pat. Nos. 2,777,874, 2,695,910, and 2,616,904. These
include the alcoholic and phenolic promoters. The alcoholic
promoters include the alkanols of 1 to 12 carbon atoms such as
methanol, ethanol, amyl alcohol, octanol, isopropanol, and mixtures
of these and the like. Phenolic promoters include a variety of
hydroxy-substituted benzenes and naphthalenes. Mixtures of various
promoters are sometimes used.
[0057] The overbased salt may also be a borated complex. Borated
complexes of this type can be prepared by heating the basic metal
salt with boric acid at about 50-100.degree. C., the number of
equivalents of boric acid being roughly equal to the number of
equivalents of metal in the salt. U.S. Pat. No. 3,929,650 discloses
such borated complexes and their preparation.
[0058] Suitable overbased detergents also include those derived
from phenol and alkylated phenols, which may be referred to as
phenates, for example calcium phenate sulfides. The phenate may be
a sulphur-containing phenate, a methylene-bridged phenate, or
mixtures thereof. In one embodiment the phenate is
sulphur-containing/coupled phenate. Such materials are described in
U.S. Pat. No. 6,551,965 and EP Publications EP 1903093 A, EP
0601721 A, EP 0271262B2 and EP 0273588 B2.
[0059] Suitable phenate detergents may be formed by reacting an
alkylphenol, an alkaline earth metal base and sulfur, typically
carried out in the presence of a promoter solvent to form a
sulfurized metal phenate. The alkylphenols useful in the present
invention are of the formula R(C.sub.6H.sub.4)OH where R is a
straight chain or branched chain alkyl group having from 8 to 40 or
from 10 to 30 carbons, and the moiety (C.sub.6H.sub.4) is a benzene
ring. Examples of suitable alkyl groups include octyl, decyl,
dodecyl, tetradecyl, and hexadecyl groups
[0060] The alkaline earth metal base can be any of those described
above and in some embodiments are calcium and/or magnesium.
Examples include calcium oxide, calcium hydroxide, barium oxide,
barium hydroxide, magnesium oxide, and the like. Calcium hydroxide,
also called hydrated lime, is most commonly used. The promoter
solvent, also called a mutual solvent, can be any stable organic
liquid which has appreciable solubility for the alkaline earth
metal base, the alkylphenol, and the sulfurized metal phenate
intermediate. Suitable solvents include glycols and glycol
monoethers such as ethylene glycol, 1,4-butane diol, and
derivatives of ethylene glycol, such as monomethyl ether, monoethyl
ether, etc. In one embodiment the solvent is one or more vicinal
glycols and in another embodiment the solvent includes ethylene
glycol. The sulfur used in the reaction may be elemental sulfur, in
the form of molten sulfur.
[0061] In some embodiments the phenate detergent is prepared in the
presence of a co-surfactant. Suitable co-surfactants include low
base alkylbenzene sulfonates, hydrocarbyl substituted acylating
agents such as polyisobutenyl succinic anhydrides (PIBSA), and
succinimide dispersants such as polyisobutenyl succinimides.
Suitable sulfonates include sulfonic acid salts having a molecular
weight preferably of more than 400 obtained by sulfonating
alkyl-benzenes derived from olefins or polymers of C2-C4 olefins of
chain length C15-C80 and alkaline earth metals such as calcium,
barium, magnesium etc. Suitable co-surfactants include and/or may
be derived from PIMA, which may itself be derived from 300 to 5000,
or 500 to 3000, or 800 to 1600 number average molecular weight
polyisobutylene.
[0062] As noted above, these phenate detergents are overbased by
reacting them with carbon dioxide gas in the presence of additional
alkaline earth meal base, typically in the presence of a promoter
solvent. In one embodiment, the phenate sulfide detergents of the
composition can be represented by Formula (V):
##STR00005##
wherein the number of sulphur atoms y can be in the range from 1 to
8, 6 or 4; R.sup.5 can be hydrogen or hydrocarbyl groups; T is
hydrogen or an (S).sub.y linkage terminating in hydrogen, an ion or
a non-phenolic hydrocarbyl group; w can be an integer from 0 to 4;
and M is hydrogen, a valence of a metal ion, an ammonium ion and
mixtures thereof.
[0063] When M is an equivalent of a metal ion, the metal can be
monovalent, divalent, trivalent or mixtures of such metals. When
monovalent, the metal M can be an alkali metal, such as lithium,
sodium, potassium or combinations thereof. When divalent, the metal
M can be an alkaline earth metal, such as magnesium, calcium,
barium or mixtures of such metals. When trivalent, the metal M can
be aluminum. In one embodiment the metal is an alkaline earth metal
and in another embodiment the metal is calcium.
[0064] The monomeric units of the above combine in such a way with
itself x number of times to form oligomers of hydrocarbyl phenol.
Oligomers are described as dimers, trimers, tetramers, pentamers
and hexamers when x is equal to 0, 1, 2, 3, and 4. Typically the
number of oligomers represented by x can be in the range from 0, 1
to 10, 9, 8, 6, 5 or even 2. Typically an oligomer is present in
significant quantities if concentrations are above 0.1, 1 or even 2
percent by weight. Typically an oligomer is present in trace
amounts if concentrations are less than 0.1 percent by weight.
Generally for at least 50 percent of the molecules, x is 2 or
higher. In some embodiments the overall sulfur-containing phenate
detergent contains less than 20 percent by weight dimeric
structures.
[0065] In the structure above each R.sup.5 can be hydrogen or a
hydrocarbyl group containing from 4, 6, 8 or 9 to 80, 45, 30 or 20
carbon atoms, or 14 carbon atoms. The number of R.sup.5
substituents (w) other than hydrogen on each aromatic ring can be
in the range from 0 or 1 to 4, 3 or 2, or be just 1. Where two or
more hydrocarbyl groups are present they may be the same or
different and the minimum total number of carbon atoms present in
the hydrocarbyl substituents on all the rings, to ensure oil
solubility, can be 8 or 9. The preferred components include
4-alkylated phenols containing alkyl groups with the number of
carbon atoms between 9 and 14, for example 9, 10, 11, 12, 13, 14
and mixtures thereof. The 4-alkylated phenols typically contain
sulphur at position 2. The phenate detergent represented by the
structure above may also be overbased using an alkaline earth metal
base, such as calcium hydroxide.
[0066] In some embodiments the phenate detergent used in the
present invention is an overbased sulfurized alkaline earth metal
hydrocarbyl phenate, which may optionally be modified by the
incorporation of at least one carboxylic acid having the formula:
R--CH(R.sup.1)--COOH where R is a C.sub.10 to C.sub.24 straight
chain alkyl group and R.sup.1 is hydrogen, or an anhydride or ester
thereof. Such overbased phenates may be prepared by reacting: (i) a
non-overbased sulfurized alkaline earth metal hydrocarbyl phenate
as described above, (ii) an alkaline earth metal base which may be
added as a whole or in increments, (iii) either a polyhydric
alcohol having from 2 to 4 carbon atoms, a di- or tri-(C.sub.2 to
C.sub.4) glycol, an alkylene glycol alkyl ether or a polyalkylene
glycol alkyl ether, (iv) a lubricating oil present as a diluent,
(v) carbon dioxide added subsequent to each addition of component
(ii), and optionally (vi) at least one carboxylic acid as defined
above.
[0067] Component (ii) may be any of the earth metal based described
above and in some embodiments is calcium hydroxide.
[0068] Component (iii) may suitably be either a dihydric alcohol,
for example ethylene glycol or propylene glycol, or a trihydric
alcohol, for example glycerol. The di- or tri-(C.sub.2 to C.sub.4)
glycol may suitably be either diethylene glycol or triethylene
glycol. The alkylene glycol alkyl ether or polyalkylene glycol
alkyl ether may suitably be of the formula:
R(OR.sup.1).sub.xOR.sup.2 where R is a C.sub.1 to C.sub.6 alkyl
group, R.sup.1 is an alkylene group, R.sup.2 is hydrogen or C.sub.1
to C.sub.6 alkyl and x is an integer in the range from 1 to 6.
Suitable examples include the monomethyl or dimethyl ethers of
ethyleneglycol, diethylene glycol, triethylene glycol or
tetraethylene glycol. A particularly suitable solvent is methyl
digol. Mixtures of glycols and glycol ethers may also be employed.
In some embodiments the glycol or glycol ether is used in
combination with an inorganic halide. In one embodiment, component
(c) is either ethylene glycol or methyl digol, the latter in
combination with ammonium chloride and acetic acid.
[0069] In some embodiments, component (vi), the carboxylic acid
used to modify the phenate has an R group that is an unbranched
alkyl group, which may contain from 10 to 24 or 18 to 24 carbon
atoms. Examples of suitable saturated carboxylic acids include
capric acid, lauric acid, myristic acid, palmitic acid, stearic
acid, arachidic acid, behenic acid and lignoceric acid. Mixtures of
acids may also be employed. Instead of, or in addition to, the
carboxylic acid, there may be used the acid anhydride or the ester
derivatives of the acid, preferably the acid anhydride. In one
embodiment the acid used is stearic acid.
[0070] In some embodiments sulfur, additional to that already
present in component (i), may be added to the reaction. The
reaction may be carried out in the presence of a catalyst. Suitable
catalysts include hydrogen chloride, calcium chloride, ammonium
chloride, aluminum chloride and zinc chloride.
[0071] In one embodiment, the overbased detergent of the present
invention is any one or more of the following: an overbased
detergent derived from an alkylated phenol, which itself may be
derived from conventional PIB; a calcium sulfonate overbased
detergent derived from a sulfonic acid, which itself may be derived
from conventional PIB, and optionally borated versions thereof. In
some embodiments the detergents have a TBN of at least 200, 250 or
290. In other embodiments the calcium sulfonates of the present
invention have a TBN of at least 270 or 280. In any such
embodiments the TBN of the overbased detergent may be less than
500, 450 or even no more than 400.
[0072] In some embodiments the overbased detergents used in the
stabilizing component of the present invention may include one or
more of the overbased sulfonates described above having a TBN of at
least 200 or 280. The detergents may also include any of the
overbased phenate detergents described above having a TBN of at
least 30, 50, 120, or at least 200 or 250.
The Alkyl Imidazoline.
[0073] In some embodiments the stabilizing component includes an
alkyl imidazoline. Such materials may be derived from the reaction
of a carboxylic acid and an amine, including an alkylene
polyamine.
[0074] In some embodiments the alkyl imidazoline may also include a
reaction product of a hydrocarbyl-substituted succinic acylating
agent and a polyamine. Such materials are described in U.S. Pat.
No. 4,234,435. However, in some embodiments the alkyl imidazolines
of the present invention do not include additives derived from
hydrocarbyl-substituted succinic acylating agents.
[0075] In other embodiments the alkyl imidazoline the condensation
product of a fatty hydrocarbyl monocarboxylic acylating agent, such
as a fatty acid, with a polyamine.
[0076] The hydrocarbyl portion of the fatty hydrocarbyl
monocarboxylic acylating agent can be an aliphatic group. The
aliphatic group can be linear, branched, or a mixture thereof. The
aliphatic group can be saturated, unsaturated, or a mixture
thereof. The aliphatic group can have 1 to 50 carbon atoms, in
another instance 2 to 30 carbon atoms, and in a further instance 4
to 22 carbon atoms, preferably 8, 10, or 12, to 20 carbon atoms. If
the fatty hydrocarbyl moncarboxylic acylating agent is an aliphatic
carboxylic acid, it may be seen as comprising a carboxy group
(COOH) and an aliphatic group. Thus, the total number of carbon
atoms in the carboxylic acid can be from 2, 3, 5, 9 or 13 up to 51,
31, 23, 11, or 21. The monocarboxylic acylating agent can be a
monocarboxylic acid or a reactive equivalent thereof, such as an
anhydride, an ester, or an acid halide such as stearoyl chloride.
Useful monocarboxylic acylating agents are available commercially
from numerous suppliers and include tall oil fatty acids, oleic
acid, stearic acid and isostearic acid. In some embodiment the
fatty acids contain 12 to 24 carbon atoms, and in some embodiment
18 carbon atoms, such as stearic acid, isostearic acid, and
combinations thereof.
[0077] A polyamine is an amine having two or more amine groups
where a first amine group is a primary amine group and a second
amine group is a primary or secondary amine group. The reaction
product of the carboxylic acid and the polyamine can contain, in
greater or lesser amounts depending on reaction conditions, a
heterocyclic reaction product such as 2-imidazoline reaction
products as well as amide condensation products. The polyamine can
have 2 to 30 carbon atoms and in some embodiments includes
alkylenediamines, N-alkyl alkylenediamines, and
polyalkylenepolyamines. Useful polyamines include ethylenediamine,
1,2-diaminopropane, N-methylethylenediamine,
N-tallow(C.sub.16-C.sub.18)-1,3-propylenediamine,
N-oleyl-1,3-propylenediamine, polyethylenepolyamines such as
diethylenetriamine and tri ethylenetetramine and
tetraethylenepentamine and polyethylenepolyamine bottoms.
[0078] In another embodiment of the invention the monocarboxylic
acylating agent and the polyamine are respectively a C.sub.4 to
C.sub.22 fatty carboxylic acid and an alkylenediamine or a
polyalkylenepolyamine, and in a further embodiment the fatty
carboxylic acid is isostearic acid and the polyamine is a
polyethylenepolyamine such as tetraethylenepentamine.
The Phosphorus Containing Additive.
[0079] The stabilizing component may also include a phosphorus
containing additive, such as a hydrocarbyl phosphate, a hydrocarbyl
thiophosphate, a di-hydrocarbyl dithiophosphate, or combinations
thereof, as well as amine salts of one or more such materials. Such
additives are generally prepared by reacting one or more phosphorus
acids, such as a phosphoric or thiophosphoric acid, including
dithiophosphoric acid, with an unsaturated amide, such as an
acrylamide, and also include amine salts of full or partial esters
of phosphoric or thiophosphoric acids.
[0080] Phosphorus-containing acids suitable for use in preparing
the stabilizing component of the present invention include
phosphorus acid esters prepared by reacting one or more phosphorus
acids or anhydrides with an alcohol. The alcohol used may contain
up to about 30, 24, 12 or even 3 carbon atoms. The phosphorus acid
or anhydride may be an inorganic phosphorus reagent, such as
phosphorus pentoxide, phosphorus trioxide, phosphorus tetraoxide,
phosphorus acid, phosphorus halide, lower phosphorus esters, or a
phosphorus sulfide, including phosphorus pentasulfide. In some
embodiments the phosphorus acid is phosphorus pentoxide, phosphorus
pentasulfide, phosphorus trichloride, or combinations thereof. The
phosphorus acid ester may be a mono- or diester of phosphoric acid
or mixtures thereof.
[0081] Examples of commercially available alcohols include Alfol
810 (a mixture of primarily straight chain, primary alcohols having
from 8 to 10 carbon atoms); Alfol 1218 (a mixture of synthetic,
primary, straight-chain alcohols containing 12 to 18 carbon atoms);
Alfol 20+ alcohols (mixtures of C.sub.18-C.sub.28 primary alcohols
having mostly Cm); and Alfol 22+ alcohols (C.sub.18-C.sub.28
primary alcohols containing primarily C.sub.22 alcohols).
[0082] In another embodiment, the phosphorus-containing acid is a
thiophosphorus acid ester and may be a mono- or dithiophosphorus
acid ester. Thiophosphorus acid esters are also referred to as
thiophosphoric acids. The thiophosphorus acid ester may be prepared
by reacting a phosphorus sulfide, such as those described above,
with any of the alcohols described above. Monothiophosphoric acid
esters, or monothiophosphates, may be prepared by the reaction of a
sulfur source, such as elemental sulfur, with a dihydrocarbyl
phosphite. The sulfur source may also be an organosufide, such as a
sulfur coupled olefin or dithiophosphate. Monothiophosphates may
also be formed in the lubricant blend by adding a dihydrocarbyl
phosphite to a lubricating composition containing a sulfur source,
such as a sulfurized olefin.
[0083] Dithiophosphoric acids, or phosphorodithioic acids, may be
reacted with an epoxide or a glycol and further reacted with a
phosphorus acid, anhydride, or lower ester. The epoxide may be an
aliphatic epoxide or a styrene oxide, such as ethylene oxide,
propylene oxide, butene oxide, octene oxide, dodecene oxide, and
styrene oxide. In one embodiment propylene oxide is used. The
glycols may be aliphatic glycols having from for 2 to 12, 6 or 3
carbon atoms. The materials may be reacted with P.sub.2O.sub.5 and
then salted with an amine.
[0084] The acidic phosphoric acid esters described above may be
reacted with ammonia or an amine compound to form an ammonium salt.
The salts may be formed separately and then the salt of the
phosphorus acid ester may be added to the lubricating composition.
Alternately, the salts may also be formed in situ when the acidic
phosphorus acid ester is blended with other components to form a
fully formulated lubricating composition.
[0085] Suitable amines include monoamines and polyamines, including
those described above. The amines may be primary amines, secondary
amines or tertiary amines. Useful monoamines may contain from 1 to
24, 14 or 8 carbon atoms, including methylamine, ethylamine,
propylamine, butylamine, octylamine, and dodecylamine,
dimethylamine, diethylamine, dipropylamine, dibutylamine, methyl
butylamine, ethyl hexylamine, trimethylamine, tributylamine, methyl
diethylamine, ethyl dibutylamine and the like.
[0086] In one embodiment, the amine may be a fatty (C.sub.4-30)
amine that include but are not limited to n-hexylamine,
n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine,
n-hexadecylamine, n-octadecylamine, oleylamine and the like. Some
examples are commercially available fatty amines such as "Armeen"
amines (products available from Armak Chemicals, Chicago, Ill.),
such as Armak's Armeen-C, Armeen-O, Armeen-OL, Armeen-T, Armeen-HT,
Armeen S and Armeen SD, wherein the letter designation relates to
the fatty group, such as cocoa, oleyl, tallow, or soya groups.
[0087] A useful amine is a C12-14 branched tertiary alkyl primary
amine supplied by Rohm and Haas under the trade name Primene 81R.
In one embodiment, the stabilizing component is an amine salt of a
mixture of phosphoric acids and esters and/or an amine salt of a
mixture of dithiophosphoric acids and esters, where the mixtures
are salted with Primene 81R or a similar amine or mixture of
amines.
[0088] The preparation of these phosphorus containing additives,
including the amine salts of the acids and esters described above,
is discussed in greater detail in U.S. Pat. No. 6,617,287.
[0089] In one embodiment the phosphorus containing additive of the
present invention is one or more of the following: a mixture of
phosphoric acids, such as hydrocarbyl phosphates, hydrocarbyl
thiophosphates, hydrocarbyl dithiophosphates, and combinations
thereof including di-hydrocarbyl versions thereof; an amine salt of
a mixture of such phosphoric acids and/or full or partial esters
thereof; (viii) an amine salt of a mixture of such dithiophosphoric
acids and/or full or partial esters.
The Alkylbenzene Sulfonate.
[0090] The sulfonic acids described above as suitable for preparing
the overbased detergents, may also be used themselves as
stabilizing agents. In one embodiment the stabilizing agent
includes sulfonic and thiosulfonic acids, and salts thereof, and
also include mono or polynuclear aromatic or cycloaliphatic
compounds. Such sulfonates are typically oil-soluble sulfonates and
in some embodiments are represented by one of the following
formulae: R.sub.2-T-(SO.sub.3.sup.-).sub.a and
R.sub.3--(SO.sub.3.sup.-).sub.b, wherein T is a cyclic nucleus such
as benzene, toluene, naphthalene, anthracene, diphenyl oxide,
diphenyl sulfide, petroleum naphthenes, or combinations thereof;
R.sub.2 is an aliphatic group such as alkyl, alkenyl, alkoxy,
alkoxyalkyl, or combinations thereof; (R.sub.2)+T contains a total
of at least 15 carbon atoms; and R.sub.3 is an aliphatic
hydrocarbyl group containing at least 15 carbon atoms. R.sub.3 may
be an alkyl, alkenyl, alkoxyalkyl, or carboalkoxyalkyl group. In
one embodiment, the sulfonic acids have a substituent (R.sub.2 or
R.sub.3) derived from one of the above-described polyalkenes, and
in some embodiments may be derived from PIB, as described above. In
one embodiment the stabilizing agent of the present invention
includes an alkyl benzene sulfonic acid where the alkyl group is
derived from PIB.
[0091] The production of sulfonates from detergent manufactured
by-products by reaction with, e.g., SO.sub.3, is well known to
those skilled in the art. See, for example, the article
"Sulfonates" in Kirk-Othmer "Encyclopedia of Chemical Technology",
Second Edition, Vol. 19, pp. 291 et seq. published by John Wiley
& Sons, N.Y. (1969).
[0092] In some embodiments the stabilizing component of the present
invention includes a compound that may be represented by Formula
VI.
##STR00006##
wherein: X.sup.1 is an oxygen atom, a sulfur atom a hydrocarbylene
group or --NR.sup.2; X.sup.2 is an oxygen atom or a sulfur atom;
X.sup.3 is .dbd.P(OR.sup.2)<, or .dbd.S(O)<; and Y is
--R.sup.2, or --OR.sup.2; each R.sup.1 is a hydrocarbylene group;
each R.sup.2 is independently a hydrocarbyl group or --H; and each
n is independently 0 or 1. In some embodiments the stabilizing
component of the present invention includes a salted version of one
or more of the compound described above. In any of the embodiments
described above, X.sup.2 of Formula VI may also be a hydrocarbyl
group and X.sup.3 may be .dbd.C< where the hydrocarbyl group of
X.sup.2 may be attached to the carbon atom of X.sup.3 by either a
double bond as shown in the formula or but a single bond. In still
other embodiments, X.sup.2 of Formula VI is a hydrocarbyl group and
X.sup.3 is .dbd.C< while the n for the [R.sup.1] group is 0.
Various stabilizing components, including many of those described
above, fall under this formula and/or at least one of its described
embodiments.
[0093] In some embodiments the stabilizing components include
compounds that comprise two anchor points and a solubilizing
element. An anchor point may be an electron donor, such as an H
bond acceptor, and/or an electron acceptor, such as an H bond
donor. In some embodiments the two anchor points are in close
proximity to one another within the molecule of the compound in the
stabilizing component. For example the anchor point may be within
10, 8, 6 or even 4 carbon atoms of one another. In some embodiments
the anchor points are within 2 carbon atoms of one another or even
connected to adjacent carbon atoms. The solubilizing element may be
a hydrocarbyl group long enough to provide the compound some level
of solubility in the medium. The solubilizing element may also be a
micelle to which the compound is attached, thus holding it in the
medium. Many of the stabilizing components described above meet
these requirements, as do various amide and acid compounds that fit
Formula VI above.
INDUSTRIAL APPLICATION
[0094] The present invention includes a process of preparing a
composition that includes combining: (a) a medium comprising a
solvent, a functional fluid, or combinations thereof; (b) a
friction modifier component that is not fully soluble in the
medium; and (c) a stabilizing component that is soluble in (a) and
that interacts with (b) such that (b)'s solubility in (a) is
improved. The processes of the present invention involve adding
components (b) and (c) to component (a) and mixing the components
so that particles of components (b) and (c) have an average
diameter of less than 10 microns. The processes of the present
invention results in a mixture that is clear and/or stable in that
the friction modifier does not drop out of solution, does not make
the mixture appear cloudy or hazy, stays suspended, dispersed
and/or dissolved in the mixture, or combinations thereof, or that
at least shows improvement in one or more of these areas when
compared to an identical composition that does not contain the
stabilizing component.
[0095] While not wishing to be bound by theory, it is believed that
in at least some embodiments the compositions of the present
invention improve the stability and/or compatibility of the
friction modifier component in the overall composition due to the
friction modifier component being solubilized in a complex with the
solubilizer.
[0096] In some embodiments the processes of the present invention
result in a mixture with an improved clarity, as defined by a lower
JTU and/or NTU value, compared to the same composition that does
not contain the stabilizing component.
[0097] As noted above, components (b) and (c) may be present in
component (a) in the form of dispersed particles having an average
diameter of less than 10 microns. In some embodiments the particles
have an average diameter of less than 10, 5 or 3 microns. In other
embodiments, the particles have an average diameter of from 0.01,
0.02, 0.03 or 0.09 to 10, 6, 5 or 3 microns. In some embodiments
80% of the particles meet one or more of the size limitations
described above. In other embodiments 90%, 95%, 99% or even 100% of
the particles meet the size limits. The means by which the
particles are formed is not overly limited, and may include the
mixing of components (a), (b) and (c) using conventional equipment
and/or techniques.
[0098] In some embodiments the compositions of the present
invention and/or the compositions that result from the processes of
the present invention include both finished functional fluids and
additive concentrates. Finished functional fluids are fluids that
are ready for use. Additive concentrates are compositions that may
contain all of the additives required for a finished fluid, but in
concentrated form. This makes shipment and handling easier. At the
appropriate time, the additive concentrate may be blended with a
fluid, solvent, or similar diluent, as well as additional
additives, to produce a finished functional fluid that is ready for
use.
[0099] When referring to finished functional fluids, the
compositions involved with the present invention may include: from
1, 3 or 10 to 99, 80 or 70 percent by weight of component (a), the
medium; from 0.1, 0.2, 0.3, 0.5 or 1.0 to 10, 7.5, 5, 4 or 3
percent by weight of component (b), the friction modifier; and from
0.1, 0.2, 0.3, 0.5 or 2.0 to 20, 10, 8, 5, 4 or 2 percent by weight
of component (c), the stabilizing component.
[0100] When referring to additive concentrates, the compositions
involved with the present invention may include: from 0.1, 1, 3 or
10 to 90, 60, 50, 30, or 20 percent by weight of component (a), the
medium; from 0.1, 0.5, 1, 5 or 8 to 60, 30, 20 or 10 percent by
weight of component (b), the friction modifier; and from 0.1, 0.2,
0.3, 0.5 or 2.0 to 20, 10, 8, 5, 4 or 2 percent by weight of
component (c), the stabilizing component. As noted above in some
embodiments the medium and the stabilizing component may be the
same material, in which case the duel functioning material may be
present in any of the ranges provided above for either component
(a) or (c).
[0101] In some embodiments the compositions of the present
invention are formed by mixing components (b) and (c) into
component (a) such that component (b) forms small particles within
component (a) and component (c) acts to stabilize these particles.
In some embodiments component (c) and component (b) form mixed
particles in component (a). In some embodiments some or all of the
particles formed are within the sizes described above. In other
embodiments, some or even all of the particles are larger than
those described above.
[0102] In some embodiments the components of the present invention
are mixed by conventional means. The amount of mixing required
varies from composition to composition and is that sufficient to
produce the particles of the desired size and/or stability. In some
embodiments the mixing may be accomplished by milling the
components and in still other embodiments the mixing may be
accomplished by milling the components at low temperature.
[0103] In one such embodiment, a friction modifier may be mixed
into oil in the presence stabilizing component, such as a
succinimide dispersant, for example polyisobutylene succinimide.
The mixing may be in the form of a milling process using
conventional milling equipment and techniques. However, in some
embodiments the milling is completed at low temperatures, in some
embodiments from at less than 30 degrees C. and in other
embodiments from -10, 0 or 5 to 30, 25 or 20 degrees C. The low
temperature milling may be achieved by cooled milling equipment,
pre-cooled components, adding a chilling agent such as dry ice
(solid carbon dioxide) to the components during milling, or a
combination thereof. The resulting compositions in some embodiments
may be described as stable dispersions and in other embodiments may
be described as solubilized solutions, or even combinations
thereof, where the main difference between such embodiments may be
the size of the particles involved.
[0104] In other embodiments the compositions of present invention
are not formed by milling or any other high-energy input methods,
but rather are formed with simple mixing and very little mechanical
energy input.
[0105] In some embodiments the functional fluid with which the
compositions of the invention are used is a fuel. The fuel
compositions of the present invention comprise the stabilized
compositions described above and a liquid fuel, and is useful in
fueling an internal combustion engine or an open flame burner.
These compositions may also contain one or more additional
additives described herein. In some embodiments, the fuels suitable
for use in the present invention include any commercially available
fuel, and in some embodiments any commercially available diesel
fuel and/or biofuel.
[0106] The description that follows of the types of fuels suitable
for use in the present invention refer to the fuel that may be
present in the additive containing compositions of the present
invention as well as the fuel and/or fuel additive concentrate
compositions to which the additive containing compositions may be
added.
[0107] Fuels suitable for use in the present invention are not
overly limited. Generally, suitable fuels are normally liquid at
ambient conditions e.g., room temperature (20 to 30.degree. C.) or
are normally liquid at operating conditions. The fuel can be a
hydrocarbon fuel, non-hydrocarbon fuel, or mixture thereof.
[0108] The hydrocarbon fuel can be a petroleum distillate,
including a gasoline as defined by ASTM specification D4814, or a
diesel fuel, as defined by ASTM specification D975. In one
embodiment the liquid fuel is a gasoline, and in another embodiment
the liquid fuel is a non-leaded gasoline. In another embodiment the
liquid fuel is a diesel fuel. The hydrocarbon fuel can be a
hydrocarbon prepared by a gas to liquid process to include for
example hydrocarbons prepared by a process such as the
Fischer-Tropsch process. In some embodiments, the fuel used in the
present invention is a diesel fuel, a biodiesel fuel, or
combinations thereof.
[0109] Suitable fuels also include heavier fuel oils, such as
number 5 and number 6 fuel oils, which are also referred to as
residual fuel oils, heavy fuel oils, and/or furnace fuel oils. Such
fuels may be used alone or mixed with other, typically lighter,
fuels to form mixtures with lower viscosities. Bunker fuels are
also included, which are generally used in marine engines. These
types of fuels have high viscosities and may be solids at ambient
conditions, but are liquid when heated and supplied to the engine
or burner it is fueling.
[0110] The non-hydrocarbon fuel can be an oxygen containing
composition, often referred to as an oxygenate, which includes
alcohols, ethers, ketones, esters of a carboxylic acids,
nitroalkanes, or mixtures thereof. Non-hydrocarbon fuels can
include methanol, ethanol, methyl t-butyl ether, methyl ethyl
ketone, transesterified oils and/or fats from plants and animals
such as rapeseed methyl ester and soybean methyl ester, and
nitromethane.
[0111] Mixtures of hydrocarbon and non-hydrocarbon fuels can
include, for example, gasoline and methanol and/or ethanol, diesel
fuel and ethanol, and diesel fuel and a transesterified plant oil
such as rapeseed methyl ester and other bio-derived fuels. In one
embodiment the liquid fuel is an emulsion of water in a hydrocarbon
fuel, a non-hydrocarbon fuel, or a mixture thereof.
[0112] In several embodiments of this invention the liquid fuel can
have a sulphur content on a weight basis that is 50,000 ppm or
less, 5000 ppm or less, 1000 ppm or less, 350 ppm or less, 100 ppm
or less, 50 ppm or less, or 15 ppm or less.
[0113] The liquid fuel of the invention is present in a fuel
composition in a major amount that is generally greater than 95% by
weight, and in other embodiments is present at greater than 97% by
weight, greater than 99.5% by weight, greater than 99.9% by weight,
or greater than 99.99% by weight.
[0114] The compositions described above may also include one or
more additional additives. Such additives include oxidation
inhibitors and antioxidants, friction modifiers antiwear agents,
corrosion inhibitors, or viscosity modifiers, as well as dispersant
and detergents different from those described above. These
additional additives may be present in the medium, particularly
when the medium includes a functional fluid. When present, these
additional additives may represent from 0, 0.1, 0.5 or 1 to 2, 5,
10 or 15 percent of the overall composition, when considering a
finished fluid, and from 0, 0.5, 1 or 2 to 4, 10, 20 or 40 percent
of the overall composition, when considering an additive
concentrate.
[0115] As allowed for by the ranges above, in one embodiment, the
additive concentrate may comprise the additives of the present
invention and be substantially free of any additional solvent. In
these embodiments the additive concentrate containing the additives
of the present invention is neat, in that it does not contain any
additional solvent added to improve the material handling
characteristics of the concentrate, such as its viscosity.
[0116] As used herein, the terms hydrocarbyl and/or hydrocarbylene
substituent and/or group are used in their ordinary sense, which is
well-known to those skilled in the art. Specifically, each refers
to a group having a carbon atom directly attached to the remainder
of the molecule and having predominantly hydrocarbon character.
Examples include: 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 a ring);
substituted hydrocarbon substituents, that is, substituents
containing non-hydrocarbon groups which, in the context of this
invention, do not alter the predominantly hydrocarbon nature of the
substituent (e.g., halo (especially chloro and fluoro), hydroxy,
alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy);
hetero substituents, that is, substituents which, while having a
predominantly hydrocarbon character, in the context of this
invention, contain other than carbon in a ring or chain otherwise
composed of carbon atoms. Heteroatoms include sulfur, oxygen,
nitrogen, and encompass substituents 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.
[0117] It is known that some of the materials described above may
interact in the final formulation, so that the components of the
final formulation may be different from those that are initially
added. For instance, metal ions (of, e.g., a detergent) can migrate
to other acidic or anionic sites of other molecules. In addition
the acylating agents and/or substituted hydrocarbon additives of
the present invention may form salts or other complexes and/or
derivatives, when interacting with other components of the
compositions in which they are used. The products formed thereby,
including the products formed upon employing the composition of the
present invention in its intended use, may not be susceptible of
easy description. Nevertheless, all such modifications and reaction
products are included within the scope of the present invention;
the present invention encompasses the composition prepared by
admixing the components described above.
[0118] As allowed for by the ranges above, in one embodiment, the
additive concentrate may comprise the additives of the present
invention and be substantially free of any additional solvent. In
these embodiments the additive concentrate containing the additives
of the present invention is neat, in that it does not contain any
additional solvent added to improve the material handling
characteristics of the concentrate, such as its viscosity.
[0119] Unless otherwise indicates all percent values and ppm values
herein are weight percent values and/or calculated on a weight
basis.
EXAMPLES
[0120] The invention will be further illustrated by the following
examples, which sets forth particularly advantageous embodiments.
While the examples are provided to illustrate the present
invention, they are not intended to limit it
Example Set 1
[0121] A sample set is prepared by mixing various levels of a
stabilizing component with friction modifier component known to
have compatibility issues into a lubricating composition. The
samples are prepared by adding a specified amount of friction
modifier to a set of lubricating composition samples and then
adding specified, increasing amounts of stabilizing component to
each sample. After the addition the mixtures are heated to 100
degrees C. and stirred until clear. Each sample is then cooled and
stored at room temperature. Each sample is then checked at 1 hour,
1 day, 3 days and 1 week after the being placed in storage to check
for cloudiness, haziness and/or drop out of the friction modifier.
The amount of stabilizing component required to stabilize the set
amount of friction modifier component in the lubricating
composition (that is, the minimum amount of stabilizing component
required to provide a clear lubricating composition after one week
of storage) is recorded. The steps are then repeated at another
friction modifier component concentration level.
[0122] The lubricating composition used in this sample set is a
fully formulated 0W20 GF-5 engine oil composition. The composition
is clear when 0 wt % of the friction modifier component is present.
The friction modifier used in these samples contains an amide
functional group and is formed by the reaction of a carboxylic acid
and ammonia or an amine. The stabilizing components used in these
samples include: a 300 TBN calcium sulfonate overbased detergent
(Inventive Example 1-1); an alkylbenzene sulfonic acid derived from
PIB (Inventive Example 1-2); an amine salt of a mixture of
phosphoric and/or acids dithiophosphoric and esters (Inventive
Example 1-3); an alkyl imidazoline derived from a fatty
mono-carboxylic acid and a polyamine (Inventive Example 1-4); a
borated 300 TBN calcium sulfonate overbased detergent (Inventive
Example 1-5); a non-borated polyisobutenyl succinimide dispersant
derived from a polyisobutenyl succinic anhydride derived from PIB
and a polyamine (Comparative Example 1-6).
[0123] The table below summarizes the results of the example
set.
TABLE-US-00001 TABLE 1 Results from Example Set 1. Example Wt %
Friction Min wt % of Stabilizer (Stabilizer Used) Modifier Present
Required for Clarity Ex 1-1 0.25 wt % 1.2 wt % 0.50 wt % 2.4 wt %
1.0 wt % 7.9 wt % Ex 1-2 0.25 wt % 0.13 wt % 0.50 wt % 0.25 wt %
1.0 wt % 1.0 wt % Ex 1-3 0.25 wt % 0.5 wt % 0.50 wt % 1.0 wt % 1.0
wt % 3.0 wt % Ex 14 0.25 wt % 1.0 wt % 0.50 wt % 2.0 wt % 1.0 wt %
5.0 wt % Ex 1-5 0.25 wt % 0.25 wt % 0.50 wt % 0.5 wt % 1.0 wt %
5.0wt % Comparative 0.25 wt % 5.0 wt % Ex 1-6 0.50 wt % 10.0 wt
%
[0124] The results show that the stabilizing components of the
present invention result in compositions that have good stability.
Further, the results show that the stabilizing components of the
present invention perform surprisingly better than a non-borated
polyisobutenyl succinimide dispersant derived from a polyisobutenyl
succinic anhydride derived from PIB and a polyamine, as the
inventive examples are required at much lower treat rates to
provide a stable blend compared to the comparative example.
[0125] Each of the documents referred to above is incorporated
herein by reference. Except in the Examples, or where otherwise
explicitly indicated, all numerical quantities in this description
specifying amounts of materials, reaction conditions, molecular
weights, number of carbon atoms, and the like, are to be understood
as modified by the word "about."
[0126] Unless otherwise indicated, each chemical or composition
referred to herein should be interpreted as being a commercial
grade material which may contain the isomers, by-products,
derivatives, and other such materials which are normally understood
to be present in the commercial grade. However, the amount of each
chemical component is presented exclusive of any solvent or
diluent, which may be customarily present in the commercial
material, unless otherwise indicated. It is to be understood that
the upper and lower amount, range, and ratio limits set forth
herein may be independently combined. Similarly, the ranges and
amounts for each element of the invention can be used together with
ranges or amounts for any of the other elements. As used herein,
the expression "consisting essentially of" permits the inclusion of
substances that do not materially affect the basic and novel
characteristics of the composition under consideration.
* * * * *