Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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L-2208R
Title: M~TAL SALTS OF HYDROCARBYL SUBSTITUT2D
AROMATIC PHOSPHORODITHIOI~` ACIDS
BACRGROUND QF THE IN~EN~IQ~
The present invention relates to a mixture of
metal salts containing low and/or high hydrocarbyl
substituted aromatic phosphorodithioic acids. It also
relates to aromatic phosphorodithioic acids having only
low but different hydrocarbyl substituents, e.g.
isomers, homologs, thereon. More specifically, the
present invention relates to such metal salts which are
oil-soluble and can be employed in the lubrication of
at least internal combustion engines~
Metal salts of phosphorodithioic acids have
been utilized as lubrican~ additives for inhibiting
corrosion and oxidation as well as improving extreme
pressure and anti-wear properties~
Various phosphorodithioic acids and their
derivatives are known.
Romanian Paten~ 75,578 relates to bis(C3_20_
alkylphenyl) phosphorodithioates and to zinc salts
thereof.
European Patent Application 0,024,146 relates
to zinc dihydrocarbyl dithiophosphates wherein the
hydrocarbyl compound includes alkyl, alkenyl, aryl,
aralkyl, alkaryl and cycloaliphatic groups. These
compounds are utilized in combination with copper
containing lubricants.
2--
A paper presented at the September 7-12, 19~9/
American Chemical Society, ~ivîsion of Petroleum
Chemistry, Inc., meeting at New York City, by Liston et
al of Chevron Corporation, relates to various types of
dihydrocarbon phosphorodithioic acids and salts there-
of. The alcohols utilized in making the salts can have
at least two carbon atoms and generally five or more.
A paper presented at the S.A.E., February
28-March 4, 1977, Detroit me~ting by Pless and Rodgers
"Cam and Lifter Wear as Affected by Engine Oil ZDP
Concentration and Typen relates to pro~ection from excess
wear by predominately alkyl ZDP instead of aryl ZDP~
U.S. Patent 2,344,393 to Cook relates to metal
dithiophosphates having one or more long chain alkyl
groups $o render them sufficiently soluble in lub-
ricating oils. Moreover, it recognized that the zinc
salt of diamylphosphorodithioic acid was oil-soluble.
U.S. Patent 2,480,673 to Reiff relates to re-
acting a hydroxyaromati~ compound with P2S5 and there-
after treating the product with finely divided zinc. The
amount of zinc utilized, however, was small and related
to removing impurities as generally opposed
to forming a salt.
U.S. Patent 2,552,570 to McNab relates to di-
hydrocarbyl phosphorodithioic acids wherein the hydro-
carbon group can be either aliphatic or aromatic and
contain a total of 10 carbon atoms in the combined
aliphatic groups, whether or not attached to an aromatic
nucleus.
U.S. Patent 3,000,822 to Higgins relates to zinc
salts of a mixture of dialkyl phosphorodithioic acids
wherein the alkyl groups comprise a mixture of lower
molecular weight primary aliphatic hydrocarbon radicals
having less than five carbon atoms and higher molecular
3;~
weight primary aliphatic hydrocarhon radicals haviny
at least five carbon atoms.
U.S. Patent 3,190,833 to Rhodes relates to
oil-soluble metal phosphorodithioates which con~ain a
total of at least 7.6 aliphatic ca~bon atoms per atom
of phosphorus. Tc improve the oil-solubility of the
metal salts, they are reacted with up to about 0.75
mole of an epoxide.
U.S. Patent 3,306,908 to LeSuer relates to
Group II metal phosphorodithioates having substan-
tially hydrocarbon radicals.
U.S. Patent 3,318,808 to Plemich discloses
that higher carbon containing alkyl groups of abov~
four carbon atoms enhance oil-solubility. The patent
also teaches the combination of C~ and lower primary
and/or secondary alcohols with C5 and above
alcohols.
U.S. Patent 3,346,493 to LeSuer also relates
to Group II metal hydrocarbon phosphorodithioates.
U.S~ Patent 3,352,949 to Rawahara relates to
certain thioesters of dithiophosphoric acid as motor
fuel additives.
U.S. Patent 3,736,110 to Ownston relates to
rust-inhibitors and more particularly to organic
imidazoline salts of mono- and dicresylic phosphates.
U.S. Patent 3,843,530 to Niedzielski relates
to preparing non-crystalline mixtures of basic or
mixed basic and neutral zinc salts of dialkyldithio-
phosphates containing from 1 to 13 carbon atoms in the
alkyl group. The mixtures of the zinc salts contain
from 4 to 13 different alkyl groups, have an average
carbon content of 3.5 to 4.5, and contain at least 12%
by weight of zinc.
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U.S. Patent 3,929,653 to Elliott relates to
certain dithiophosphate compounds which are useful as
additives. It furthermore relates to a process of
reacting a di(organo)dithiophosphoric acid and a
monocyclic, non-conjugated olefin containing from 8 to
12 carbon atoms and at least two ethylenically
unsaturated double bonds in the ring, and optionally
bearing one or more alkyl, alkoxy or hydroxy groups on
the ring.
U.S. Patent 4, 085,053 to Caspari relates to
a process for manufacturing metal dithiophosphates,
and metal dithiophosphate compositions. The alcohol
often used is an alkyl alcohol.
UOS~ Patent 4,105,571 to Shaub relates to a
storage stable lubricating composition having improved
anti-wear properties provided by a base oil composi-
tion containing an additive combination of ~1) a zinc
dihydrocarbyl dithiophosphate, (2) an ester of a
polycarboxylic acid and a glycol, and (3) an ashless
dispersant.
U.S. Patent 4,113l634 to Sabol relates to the
manufacture of metal diaryl dithiophosphates by
reacting P2S5 with a hydroxyaryl compound to form
a dithiophosphoric acid and neutralizing said acid
with metal in the presence of a promoter, said
promoter comprising dialkyl dithiophosphoric acid.
U.S. Patent 4,306,984 to Yamaguchi relates to
a procedure for rendering oil in~oluble metal
C2-C3 dialkyl dithiophosphates oil-soluble by
forming a complex between the dithiophosphate and an
alkenyl or alkyl mono- or bis-succinimide.
U.S. Patent 4,466,895 to Schroeck relates to
certain metal salts of one or more dialkylphosphoro-
dithioic acids whsrein the alkyl groups, the total
number of carbon atoms per phosphorus atom and the
like fall within specific ranges.
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SUMMA:!3Y OF THE INVENTION
Accordingly, it is an aspect of the present
invention to produce mixtures of metal salts which are
oil-solubleO
It is a further aspect of the present
invention to provide a mixture of metal salts, as
above,.wherein the reaction with the metal or the
basic me~al compound is carried out at a low
temperature to promote the salt formation.
It is another aspect of the present invention
to provide a mixture o~ metal salts, as above~ wherein
cresylic acids are utilized.
It is still a further aspect of the presen~
invention to provide a mixture of metal salts, as
above, which can function as effective anti-wear
agents.
These and other aspects of the present
invention will become apparent ~rom the attached
specification which fully describes the present
invention.
In general, metal salts of hydrocarbyl sub-
stituted aromatic phosphorodithioic acids comprise a
mixture of one or more metal salts of the aromatic
phosphorodithioic acids containing optionally (A) high
hydrocarbyl substituents, optionally ~B) low hydro-
carbyl substituents, and a high and a low hydrocarbyl
substituent.
Further, metal salts of hydrocarbyl substi-
tuted aromatic phosphorodithioic acids comprise one or
more metal salts of the aromatic phosphorodithioic
acids containing different low hydrocarbyl substi-
tuents therein.
According to the present invention, a mixture
of metal salts of aromatic phosphorodithioic acids
contains a high hydrocarbyl substituent and a low
hydrocarbyl substituent, and optionally can contain
only high hydrocarbyl substituents or only low
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hydrocarbyl substituents. That is, a high hydrocarbyl
aromatic alcohol and a low hydrocarbyl aromatic
alcohol are reacted with phosphorus sulfides to form
aromatic phosphorodithioic acids. The result
approximates a statis~ical mixture of aromatic
phosphorodithioic acids having only high hydrocarbyl
subs~ituents, only low hydrocarbyl substituents, or a
high and a low hydrocarbyl substituent. The latter
components are generally present in a greater amount
than either of the first two noted situations. With
regard to the aromatic component of the acid, it
generally can be naph~hyl with phenyl being preferred.
In another embodiment, only low but at least
2 different hydrocarbyl substituents are utilized and
hence, the end product approximates a statistical
mixture of aromatic phosphodithioic acids having only
low but often different hydrocarbyl substituents
within the same acid.
The term "hydrocarbyl substituent" or
"hydrocarbyl group" is used throughout this specifica-
tion and in the appended claims to denote a group
having a carbon atom directly attached to the
remainder of the molecule and having predominately
hydrocarbon character within the context of this
invention. Such groups include the following:
(1) Hydrocarbon groups, that is, aliphatic
(e.~., alkyl or alkenyl), alicyclic (e.g., cycloalkyl
or cycloalkenyl), aromatic, aliphatic- and alicyclic-
substituted aromatic, aromatic-substituted aliphatic
and alicyclic groups, and the like, as well as cyclic
groups wherein the ring is completed through another
portion of the molecule (that is, the two indicated
substituents may together form a cyclic group)~ Such
groups are known to those skilled in the art; examples
include methyl, ethyl, butyl, hexyl, octyl, decyl,
dodecyl, tetradecyl, octadecyl, eicosyl, cyclohexyl,
phenyl and naphthyl (all isomers being included).
~ ~ ~3
(2) Substituted hydrocar~on groups, tbat is,~
groups containing non-hydrocarbon substituents which,
in the context of this invention, do not alter pre-
dominantly hydrocarbon character of the group. Those
skilled in the art will be aware of suitable substit-
uents (e.g., halo, hydroxy, alkoxy, carbalkoxy, nitro,
alkylsulfoxy).
(3) Hetero groups; that is, groups which,
while predominantly hydrocarbon in character within
the context of this invention, contain atoms other
than carbon present in a chain or ring otherwise
composed of carbon atoms. Suitable hetero atoms will
be apparent to those skilled in the art and include,
for example, nitrogen, oxygen and sulfur.
The high hydrocarbyl substituent thereof
generally has a total of from 4 to 18 carbon atoms,
desirably from 6 to 12 carbon atoms and preferably
from about 6 to 8 carbon atoms with 7 car~on atoms
being more preferred.
The aromatic alcohol having the high
hydrocarbyl substituent therein can be represented by
the formula
OH
~(R')n
Although ~Rl)n can be suitable hydrocarbyl group(s),
desirably it is alkyl group and as noted, having a
total of 4 to 18 carbon atoms, desirably from 6 to 12
and preferably from 6 to 8 carbon atoms. The number
of the R' group(s), that is n, is from 1 to 3/ with l
being preferred. Representative examples of such
alcohols include butyl phenol, isobutyl phenol, pentyl
phenol, hexyl phenol, heptyl phenol, octyl phenol,
nonyl phenol, decyl phenol, dodecyl phenol, octadecyl
~'73 ~
phenol, dibutyl phenol, dinonyl phenol, didodecyl
phenol, triethyl ph4nol and tributyl phenol. Since n
is preferably 1 and the number of carbon atoms is
desirably 7, heptyl phenol is a preferred compound.
However, often a plurality of such high
hydrocarbyl aromatic alcohols or phenols are utilized
in making the phosphorodithioic acids~ Thus, the
various types of the high hydrocarbyl substituents on
the aromatic nucleus are classified by the average
number of total carbon atoms thereon. Generally, the
overall average number of substituent carbon atoms
(R')n is as above, that is from 4 to 18 with from 6
to 12 being desired and 6 to 8 being preferredO
The amount of the (A) high hydrocarbyl
substituted aromatic alcohols or phenols is generally
a minority based upon 100~ equivalents of said (A)
high hydrocarbyl substituted aromatic alcohols and the
(B) low hydrocarbyl substituted aromatic alcohols.
From as low as about 5 percent to about 75 percent
equivalents can be utilized with from about 10 to
about 65 percent equivalents being desired and from
about 15 to about 40 percent equivalents being
preferred.
~ he (B) low hydrocarbyl substituted aromatic
alcohols generally have a total of 4 or less carbon
atoms in the hydrocarbyl substituent. The hydrocarbyl
group can generally be any suitable substituent such
as aliphatic with an alkyl being preferred. The (B)
low hydrocarbyl substituted aromatic alcohol can be
represented by the following formula
OH
(~(R)m
\
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where (R~ can be suitable hydrocarbyl yroup(s~,
desirably it is alkyl group(s) having from O to 4
carbon atoms, desirably from 1 to 4 carbon atoms with
from 1 to 3 carbon atoms being preferred. The number
of the R group(s), that is m, is an integer of from 1
to 3 with 1 or 2 being preferred. In the situation
where R is O carbon atoms, the low hydrocarbyl sub-
~tituted aromatic alcohol is simply phenol. Phenol is
generally not desired in any large amount since it
imparts poor solubility to produc~s made therefrom. A
general class of compounds falling within the above
formulation are generally referred to as the cresylic
acids. S~ch a group of compounds usually cvntain
numerous different (B) low hydrocarbyl substituted
aromatic alcohols including the cresols from which the
name is derived. Suitable alcohols thus include
ortho-cresol, meta-cresol, para-cresol, the various
xylenols such as 2,6-xylenol, 2,4-xylenol,
2j5-xylenol, 2,3-xylenol, and 3,4-xylenol. Another
group of alcohols are the ortho, meta- and para-
ethylphenols. Still another group of alcohols are the
propyl substituted phenols. The various trimethyl
substituted phenols constitute yet another group with
specific examples including 2,3,5-trimethylphenol,
2,3,4-trimethylphenol, 2,4,5- trimethylphenol,
3,4,5-trimethylphenol and the like. An example of low
hydrocarbyl substituted aromatic alcohols containing
four substituted carbon atoms are the various tetra-
methylphenols such as 2,3,5~6- tetramethylphenol,
2,3,4,5-tetramethylphenol, 2,3,4,6- tetramethylphenol,
and the like. A still further group of such aromatic
alcohols include the various ethyl-methylphenols such
as 4-ethyl-2-methyl-phenol, 5-ethyl-2-methylphenol and
the like. Inasmuch as such aromatic alcohols are
derived from various fossil fuels and depend upon the
particular type of fossil fuel
~ ~73;~
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and/or as well as the region of the world from which~
they are obtained~ or are derived synthetically, ~he
various cresylic acids or the (B) low hydrocarbon
content substituted aromatic alcohols can vary greatly
in content.
According to the present invention, it is
important that the low hydrocarbyl substituent (R)m
con~ain an overall average of a small number of total
carbon atoms. Accordingly, all of the low hydrocarbyl
substituents, (R)m, generally contain an overall
average number of from about 0 or from about 0.5 to 4
carbon atoms, desirably from about 1.0 to about 3.5
carbon atoms, and preferably from about 2.0 to about
3.0 carbon atoms.
The amount of the low hydrocarbyl substituted
aromatic alcohols is generally from about 25 to about
. 90 percent equivalents, desirably from about 35 to
about 90 percent equivalents, and preferably from
about 60 to about 85 percent equivalents based upon
the total number of equivalents of both the (A) high
hydrocarbyl substituted aromatic alcohols and the (B)
low hydrocarbyl substituted aromatic alcohols.
Sources of low hydrocarbyl substituted
aromatic alcohols or cresyl.ic acids are numerous. A
typical example is Product CA-33 from the Merichem
Company. of Houston, Texas. Such a product ha~ an
organic composition as determined by gas chromatograph
and is set forth in Table I.
~ ~fa~ ^,Y
~a~
~QmeQgn~ ` Weig~
Phenol 0.1
O-Cresol Trace
2,6-Xylenol . Trace
P-Cresol 0.2
M-Cresol 0.6
O-Ethylphenol 0.3
2,4-Xylenol 19.4
2,5-Xylenol 19.3
2,4,6-Trimethyl Phenol 0.8
2,3-Xylenol 8.5
P-Ethylphenol 10.7
M-E~hylphenol 23.0
3,5-Xylenol 12.0
3,4-Xylenol 3.3
C3 Phenols 1.8
7;~
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The average number of carbon atoms in th~
hydrocarbyl substituent is approximately 2.07.
Another example of a cresylic acid composition
is Product CA-57~of the Merichem Company which according
to gas chromatograph has the following analysis as set
forth in Table II.
7~1e J~J2~f~
73
: -13-
TABLE II
5~ ~gh~
Phenol
O-Cresol Trace
2,6-Xylenol
P-Cresol 0.1
M-Cresol 0.2
O-Ethylphenol Trace
2,4-Xylenol 1.0
2,5-Xylenol 1.2
2,4,6-Trimethyl Phenol 0.8
2,3-Xylenol 10.7
P-Ethylphenol 15.3
r~-Ethylphenol 40.5
3,5-Xylenol 23.3
3,4-Xylenol 4.8
C3 Phenols 2.1
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The average number of carbon atoms in the
hydrocarbyl substituent is approximately 2.05.
Yet another example of a commercial cre~ylic
A acid is Product XL-85~ sold by the Productol Chemical
Division of Ferro Corporation, Whi`ttington, California.
Gas chromatograph analysis revealed the following
composition as set forth in Table III.
J~ e /t1arl~
~2~33~3
T~L~ III
C~m~ngl~ ~elgh~
Phenol Trace
Ortho Cresol Trace
Meta/Para Cresol 1.0
2,4-Xylenol Group 1.0
3,4-Xylenol Group 36.0
3,5-Xylenol Group 12.0
Higher Phenols 50.0
1~
~'7~
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The average number of carbon atoms in the hydrocarby1
substituent is approximately 2.8.
As should be apparent, there are numerous
sources and ~ypes of low hydrocarbyl substituted
aromatic alcohols which can be utilized in the present
invention with regard to the (B~ type reactant or
component.
According to another embodiment o~ the present
invention, only low hydrocarbyl substituents of the
aromatic phosphorodithioic acid are utilized. In other
words, no high hydrocarbyl subs~ituents are utilized and
hence there is no mixture o~ metal salts of the aromatic
phosphorodithioic acids containing high hydrocarbyl
substituents. ~owever, it is essential to the present
embodiment that at least two different types of low
hydrocarbyl substituents be utilized. That is, it has
been found that when different aromatic alcohols are
reacted with various types of phosphorus sulfides as
well as optional non-phosphorus containing sulfur
compounds as set forth below, the result approximates a
statistical mixture of aromatic phosphorodithioic acids
often having different hydrocarbyl substituents within
the same acid or individual molecule. Moreover, such
different low hydrocarbyl substituents within the same
individual phosphorodithioic acid have unexpectedly been
found to impart favorable solubility to such compounds.
Such favorable solubility is not contained by metal
salts made from a single type of low hydrocarbyl
substituted aromatic alcohol. In other words, mixtures
of various or different low hydrocarbyl substituted
aromatic alcohols are necessary in preparing the metal
salts of the present embodiment.
The low hydrocarbyl substituted aromatic
alcohols with regard to this embodiment can be the same
as the above (B) alcohols. That is, the alcoholx can be
represented by the formula
7~
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H
l~ (R)m
where R is an alkyl group having from O or 0.5 to 4
carbon atoms, desirably from 1 to 4 carbon atoms wi~h
from 1 to 3.5 or 3 carbon atoms being preferred. The
number of such R groups, that is m is an integer from
1 to 3 with 1 or 2 being preferred. Inasmuch as such
compounds have been described hereinabove, the des-
cription thereof will not be repeated but rather is
hereby fully incorporated by reference. However, it
is essential that these two different or distinct
alcohols be utilized to impart favorable solubility to
the metal salt. By the term "different," it is meant
that the alcohols are not identical or the same. The
term "differentn includes not only different
structural alcohols, but homologues of a particular
aromatic alcohol as well as isomers of the same
alcohol. Thus, by way of example meta, ortho and
paracresol are different alcohols. Similarly, the
various xylenols constitutes a different type of an
aromatic alcohol, for example 2,6-~ylenol, or
2,4-xylenol, or 3,4-xylenol or the like.
As set ~orth above, various sources of low
hydrocarbyl aromatic alcohols which already contain at
least two different types of alcohols therein can be
utilized such as the various cresylic acids which are
hereby incorporated by reference. The amount of the
various types of the low hydrocarbyl substituted
aromatic alcohol is such that satisfactory solubility
in a diluent oil is obtained.
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The acids of the present invention are gener
ally prepared by reacting a solution containing a
combination of both the low hydrocarbyl substituted
aromatic alcohols as well as the high hydrocarbyl
substituted aromatic alcohols, in a ràtio as set forth
within the above limits, with various types of
phosphorus sulfides. When necessary, non-phosphorus
containing sulfur compounds can be used. Alternatively,
the acids of the present invention are also generally
prepared by reacting a solution containing a mixture of
different low hydrocarbyl substituted aromatic alcohols,
in a ratio as set forth within the above limits, with
various types of phosphorus sulfides as well as optional
non-phosphorus containing sulfur compounds. Examples of
various phosphorus sulfides include P2S3, P4S3, P4S7~
Examples of optional sulfur compounds include sulfur and
sulfurized olefins. In the preparation of the acids,
the phosphorus sulfides are initially reacted with the
mixture of high and low hydrocarbyl substituted aromatic
alcohols and then optionally reacted with the
phosphorus-free sulfur compounds. Similarly, the
phosphorus sulfides are initially reacted with the
mixture of solely the low hydrocarbyl substituted
aromatic alcohols and then optionally reacted with the
phosphorus-free sulfur compounds. In any event, a
preferred phosphorus-sulfur compound is phosphorus
pentasulfide.
The preparation of the desired phosphoro-
dithioic acids generally involves a reaction of from
about 3 to about 5 moles and desirably about 4 moles of
the alcohol mixture per mole of phosphorus pentasulfide
in an inert atmosphere such as nitrogen. The reaction
is generally carried out within a temperature range of
from about 50C to about 200C, desirably from about
80C to about 200C and preferably from about 110C to
3~
-19-
about 140C. The reaction is normally completed in t~e
time period of from about 1 to 3 hours with hydrogen
sulfide being liberated during the reaction.
The metal salts of the hydrocarbyl substituted
aromatic phosphorodithioic acids are readily formed by
the reaction of the metal or the basic metal compound
with the acid. Simply mixing and heating the two
reactants together is sufficient to cause the reaction
to take place. According to the present invention, it
is important that the reaction temperature with regard
to the formation of the metal salt be kept low to avoid
excessive hydrolysis. Inasmuch as hydrolysis is to be
avoided, the reaction temperature is generally ~rom
about 30C to about 90C and preferably from about 50C
to about 80~C.
Typically, the metal salt ~ormation is carried
out in the presence of a diluent oil, a desired oil is a
low viscosity (e.g~ about 3-7 centistokes @ 40C)
naphthenic oil since it gives a fluid product.
Another aspect of the present invention is that
at the reaction temperature of the formation of the
salt, a promoter is not required. That is, the reaction
between the acid and the basic metal compound is free
from any promoter. Generally, a metal salt is desired
which is neutral or basic and hence, an equivalent or a
slight excess of the metal or the basic metal compound
is utilized to yield such an end product. Accord-
ingly, the amount of metal or basic metal compound when
utilized in an excess is from about 0 to about 20 per-
cent with an excess of from about 5 percent to about 15
percent equivalents being desirable.
Types of metals suitable for the present
invention include zinc, copper, nickel, cobalt,
manganese, potassium, tin, sodium, calcium especially in
combinations with other metals, as well as combinations
of any of the previous metals. Additionally, basic
metal compounds can be utilized such as various metal
~73
-20-
oxides, acetates and the like. Thus, examples of
specific basic metal compounds include zinc oxide,
copper oxide, sodium hydroxide, potassium hydroxide,
calcium oxide, ~inc acetate, copper acetate, and the
like. Examples of preferred metals include copper and
zinc with zinc being especially pre'ferred. Examples of
preferred basic metal compounds include zinc oxide and
copper oxide~
The metal salts of the present invention have
been found to impart good anti-wear properties to
various organic diluents. Moreover, in view of the fact
that aromatic phosphorodithioates typically give poor
anti-wear results, the fac~ that the mixtures of the
present invention give good anti-wear results was
actually unexpected.
The following examples illustrate the prepara-
tion of the phosphorodithioic acids and the metal salts
thereof. All parts and percentages are by weight unless
otherwise indicated.
Example 1~
A mixture of 2945 parts (24 equivalents) of
Cresylic Acid 57 and 1152 parts (6.0 equivalents) o
heptylphenol is heated to 105C under a nitrogen
atmosphere whereupon 1665 parts (15 equivalents) of
phosphorus pentasulfide are added in portions over a
period of 3 hours while maintaining the temperature of
the mixture between about 115-12GC. The mixture is
maintained at this temperature for an additional 1.5
hours upon completion of addition of the phosphorus
pentasulfide and then cooled to room temperature. The
reaction mixture is filtered through a filter aid, and
the filtrate is the desired phosphorodithioic acid.
ExampL~_lB
Zinc oxide ~541 parts, 13.3 equivalents), 14.4
parts (0.24 equivalents) of acetic acid and 1228 parts
of mineral oil are charged to a 12 liter flask. A
vacuum (100-100 mm) is applied while raising the
-21-
temperature to about 70C. The phosphorodithioic aci~
(4512 parts, 12.0 equi~alents) prepared in Example lA is
added over a period of about 5 hours while maintaining
the temperature at 68-72C. The water is removed as it
forms. The temperature is maintained at 68-72C for 2
hours after the addition of phosphorodithioic acid is
complete. To ensure complete removal of the water,
vacuum is adjusted to about 10 mm and the temperature is
raised to about 105C and maintained at this temperature
for 2 hours. The residue is filtered and the filtrate
is the desired product. The product contains 6.2~% P
(6.09% theory) and 6.84% Zn (6.38% theory).
ExampL~ lC
Cuprous oxide (78.7 parts, 1.1 equivalents) and
112 parts of mineral oil are charged to a one-liter
flask and 384 parts (1.0 equivalents) of the phosphoro-
dithioic acid prepared in Example lA are added over a
period of 2 hours while raising the temperature grad-
ually to about 55C. Upon completion of the addition of
the acid, the reaction mixture is maintained at about
50C. Upon completion of the addition of the acid, the
reaction mixture is maintained at about 50C for about 3
hours. A vacuum is applied while raising the tempera-
ture to about 80C. The residue is filtered and the
filtrate is the desired product. The product is a clear
liquid containing 12.0% sulfur (11.5% theory) and 12.0
copper (11.4% theory).
Example 1~
Zinc oxide (537 parts, 13.2 equivalents), 97
parts of water and 1223 parts of mineral oil are charged
to a 12-liter flask. The phosphorodithioic acid (4512
parts, 12.0 equivalents) prepared in Example lA is added
over a period of about 2 hours. The temperature is
allowed to increase from 25C to 48~C during the
addition. The temperature is increased to and main-
tained at about 70C for 3 hours after the addition of
phosphorodithioic acid is complete. To ensure complete
~7~
-22-
removal of water a vacuum (about 15 mm Hg) is appljied
and the temperature is raised to 100C. The residue is
iltered and the filtrate is the desire product. The
product contains 6.29% P (6.09% theory) and 6.80~ Zn
(6.39% theory).
E-xampLe 2A
A mixture 432 parts (4 equivalents) p-cresol
and 432 parts (4 equivalents) of m-cresol is heated to
110C under a nitrogen atmosphere whereupon 444 parts (4
equivalents) of phosphorus pentasul~ide are added in
portions over a period of 2.5 hours while maintaining
the temperature of the mixture at about 110C. The
mixture is maintained at this temperature for an
additional 1O5 hours upon completion of the addition of
the phosphorus pentasulfide and then cooled to room
temperature. The reaction mixture is filtered through a
filter aid and the filtrate is the desired phosphoro-
dithioic acid.
Example 2B
Zinc oxide (175 parts, 2.2 equivalents) 3.55
parts (0.06 equivalents) of acetic acid, 250 parts of
heptane are charged to a 3-liter flask. A vacuum is
applied while raising the temperature to about 50C.
The phosphorodithioic acid (1145 parts, 3.5 equivalents)
prepared in Example 2A is added over a period of about 2
hours while maintaining the temperature at about 60-
65C. The temperature is raised to about 80C and kept
at this temperature for 3 hours. The residue is
filtered and the filtrate is the desired product. The
product contains 9.01% P (8.59~ theory) and 9.11% Zn
(9.06% theory).
Example 3A
Heptylphenol (1540 parts, 8.0 equivalents) is
heated to 125C under a nitrogen atmosphere whereupon
444 parts (4.0 equivalents) of phosphorus pentasulfide
are added in portions over a period of 1 hour while
maintaining the temperature of the mixture at about
~'~,7 3;~
-23-
145C. The mixture is held at this temperature for an
additional 4 hours upon completion of the addition of
the phosphorus pentasulfide and then cooled to room
temperature~ The reaction mixture is ~iltered through a
filter aid and the filtrate is the desired phosphoro~
dithioic acid.
Example 3B
Zinc oxide (90.5 parts, 2.22 equivalents), 2.54
parts (0.04 equivalents) o~ acetic acid, 2.54 parts of
water, and 919 parts of mineral oil are charged to a 3
liter flask. The mixture is heated to about 70C and
1000 parts (1.83 equivalents) of the phosphorodithioic
acid of Example 3A are added over a period of 1 hour
while maintaining the temperature at 70-75C. Upon
completion of the addition of the phosphorodithioic acid
the temperature is maintained at 70 75C or 3 hours.
Vacuum is applied and the temperature is raised to about
105C. The residue is filtered and the filtrate is the
desired productO The product is a clear liquid and
contains 3.0~ P.
Example ~A
Dodecyl phenol (2100 parts, 8.0 equivalents) is
heated to 125C under a nitrogen atmosphere whereupon
444 parts (4.0 equivalents) of phosphorus pentasulfide
are added in portions over a period of 1 hour while
maintaining the temperature of th~ mixture at about
145C. The mixture is held at this temperature for an
additional 4 hours upon completion of the addition of
the phosphorus pentasulfide and then cooled to room
temperature. The reaction mixture is filtered through a
filter aid and the filtrate is the desired phosphoro-
dithioic acid~
Example 4B
Zinc oxide (90.5 parts, 2.22 equivalents), 2.54
parts ~0.04 equivalents) of acetic acid, 2.54 parts of
water, and 597 parts of mineral oil are charged to a 3
liter flask. The mixture is heated to about 70C and
-24-
1271 parts (1.83 equivalents) of the phosphorodithiolc
acid of example 4A are added over a period of 1 hour
while maintaining the temperature at 70-75C. Upon
completion of the addition of the phosphorodithioic acid
the temperature is maintained at 70-75C for 3 hours.
Vacuum is applied and the temperature is raised to about
105C. The residue is filtered and the ~iltrate is the
desired product. The product is a clear liquid and
contains 3.2% P.
Ex~ 5A
Cresylic Acid 57 (356 parts, 2.9 equivalents)
is heated to about 113C under a nitrogen atmosphere
whereupon 161 parts (1.45 equivalents) of phosphorus
pentasulfide are added in portions over a 1.5 hour
period while maintaining the temperature at 110-115C.
The mixture is held at this temperature ~or an
additional 2 hours upon completion of the addition of
phosphorus pentasulfide and then cooled to room
temperature. The reaction mixture is filtered through a
filter aid and the filtrate is the desired
phosphorodithioic acid.
Example 5B
Zinc oxide (4501 parts, 1.1 equivalents), 1.2
parts (0.02 equivalents) of acetic acid, and 96.1 parts
of mineral oil are charged to a 1 liter flask. A vacuum
(about 100 mm) was applied and the temperature was
raised to about 70C. The phosphorodithioic acid (352
parts, 1.0 equivalents) of Example 5A is added over a 2
hour period while maintaining the temperature at
72-79C. Water was removed as it formed. Upon
completion of the phosphorodithioic acid addition, the
temperature is held at 70-75C for an additional 3
hours. The mixture is filtered and the ~iltrate is the
desired product. The product is a clear liquid.
Example ~A
A mixture of 583 parts (4.75 equivalents) of
Cresylic Acid 57 and 48 parts (0.25 equivalents) of
-25-
heptylphenol is heated to 120C under a nitro~en
atmosphere whereupon 278 parts (2.5 equivalents) of
phosphorus pentasulfide are added in portions over a one
hour period while maintaining the temperature at
120-125C. The mixture is held at this temperature for
1.5 hours after the phosphorus pentasulfide addition is
complete and then cooled to room temperature. The
reaction mixture is filtered through a filter aid and
the filtrate is the desired phosphorodithioic acid.
Example 6B
Zinc oxide (45.1 parts, 1.1 equivalents), 1.2
parts (0.02 equivalents) of acetic acid, and 99.3 parts
of mineral oil are char~ed to a 1 liter flask. A vacuum
(about 100 mm) is applied while ~aising the temperature
to about 75C. The phosphorodithioic acid (365 parts,
1.0 equivalents) prepared in Example 6A is added over a
period of 2 hours while maintaining the temperature at
75-80C. The water is removed as it forms. The
temperature is maintained at about 77C for 3 hours
after the phosphorodithioic acid addition is complete.
The vacuum is reduced to about 10 mm and the temperature
is raised to about 100C and held at that temperature
for 1 hour. The residue is filtered and the filtrate is
the desired product. The product contains 7.06~ Zn
(6.53% theory).
Example 7~
A mixture of 533 parts (~.0 equivalents) of
Cresylic Acid XL-85 and 192 parts (1.0 equivalents) of
heptylphenol is heated to 95C under a nitrogen
atmosphere whereupon 278 parts (2.5 equivalents) of
phosphorus pentasulfide are added in portions over a 1
hour period while maintaining the temperature at
100-110C. The mixture is held at this temperature for
1 hour after the phosphorus pentasulfide addition is
complete and then cooled to room temperature. The
reaction mixture is filtered through a filter aid, and
the filtrate is the desired phosphorodithioic acid.
-
-26-
Example 7B
Zinc oxide (45.1 parts, 1.1 equivalents), 1.2
parts (0.02 equivalents) of acetic acid, and 107 parts
of mineral oil are charged to a 1 liter flask. The
phosphorodithioic acid (395 parts, 1.0 equivalents)
prepared in Example 7A is added ove`r a period of 1 hour
while allowing the temperature to rise to about 56C.
After the phosphorodithioic acid addition is complete,
the temperature is raised to about 70C an~ held there
for 15 minutes. A vacuum is applied and the temperature
is raised to about 100C. The residue is filtered and
the filtrate is the desired product. The product
contains 5.94% P (5.79% ~heory) and 6078~ Zn (6.07%
theory).
Exa~pl~ 8~
A mixture of 1095 parts (9 equivalents) of
Cresylic Acid 33 and 204 parts (1 equivalent) of
heptylphenol is heated to about 123C under a nitrogen
atmosphere whereupon 555 parts (5 equivalents) of
phosphorus pentasulfide are added in portions over a 2
hour period while maintaining the temperature at
120-123Co The mixture is held at this temperature for
2 hours after the phosphorus pentasulfide addition is
complete and then cooled to room temperature. The
reaction mixture is filtered and the filtrate is the
desired phosphorodithioic acid.
Exam~l~ 8B
Zinc oxide (64 parts, 1.57 equivalents, 1.6
parts (00026 equivalents) of acetic acid, and 218 parts
of xylene, are charged to a 2-liter flask. Vacuum
(about 96 mm) is applied and the mixture is heated to
about 76C. The phosphorodithioic acid (465 parts, 1l3
equivalents) prepared in Example 8A is added over a 7
hour period. Water is removed as it is formed. After
the phosphorodithioic acid addition is complete, the
temperature is raised to about 89C and held at that
-27-
temperature for 1.5 hours. Mineral oil (127 parts) is
added The pressure was reduced to about 10 mm and the
temperature was increased to about 95C to remove the
xylene. The residue is filtered and the ~iltrate is the
desired product. The product contains 6.68~ P (6.33%
theory).
Example 9A
A mixture of 241 parts (2.0 equivalents) of
Cresylic Acid 33 and 408 parts (2.0 equivalents) of
heptylphenol are heated to 90C under a nitrogen
atmosphere whereupon 222 parts (2.0 equivalents) of
phosphorus pentasulfide are added in portions over a 1
hour period. The temperature is allowed to rise to
about 120C during the addition and is maintained at
115-120C for ~ hours after the addition of phosphorus
pentasulfide is complete. The reaction mixture is
filtered and the filtrate is the desired phosphoro-
dithioic acid.
Example 9~
Zinc oxide (49.2 parts, 1~21 equivalents), 1.2
parts (0.02 equivalents) of acetic acid, and 218 parts
of xylene are charged to a 1 liter flask. Vacuum (about
94 mm Hg) is applied and the mixture is heated to about
89C. The phosphorodithioic acid (442 parts, 1.0
equivalents) prepared in Example 9A is added over a 1
hour period. The temperature is maintained at about
89C for 3 hours after the phosphorodithioic acid
addition is completed. Mineral oil (118 parts) is
added. The vacuum is adjusted to about 10 mm Hg and the
temperature is raised to about 100C to remove xylene.
The residue is filtered and the filtrate is the desired
product. The product contains 5.51% P (5.19~ theory)
and 5.72% Zn (5.44~ theory).
-28-
~xam~le 10~ ~
A mixture of 615 parts (5.0 equivalents) of
Cresylic Acid 33 and 355 parts (1.85 equivalents) of
heptylphenol is heated to 120C under a nitrogen
atmosphere. Phosphorus pentasulfide (344 parts, 3.1
equivalents) is added in portions over a 2 hour period
while maintaining the temperature of the mixture at
about 127-135C. The temperature is held at 130C ~or
1.5 hours after the addition of phosphorus pentasulfide
is complete and then cooled to room temperature. The
reaction mixture is filtered and the filtrate is the
desired phosphorodithioic acid.
~xample 10~
Zinc oxide (112 parts, 2175 equivalents) and
186 parts of mineral oil are charged to a 2 liter flask.
The phosphorodithioic acid ~1045 parts, 2~5 equivalents)
prepared in ~xample 10A is added over a 2 hour period
while allowing the temperature of the reaction mixture
to increase to about 50C. Upon completion of the
phosphorodithioic acid addition, the temperature is
increased to and maintained at about 75C for 3 hours.
Vacuum (about 15 mm Hg) is applied and the temperature
of the reaction mixture increased to about 100C. The
residue is filtered and filtrate is the desired
product. The product contains 5.98% P (5.93% theory)
and 6.79% Zn (6.22~ theory).
The products of the various examples, contained
in a fully formulated lubricating composition, were then
tested with regard to a Timken "OK" load test as well as
a contact pressure test in accordance with ASTM D 2782
with the exception that in the "OK~ load test the
following differences were made:
~7~
_~9_
1. Test cup and block surfaces are mere~y
"wetted" with test lubricant (approx-
imately 5 drops on block). No test sample
is recirculated over the surfaces during
the test.
2. Test duration is 5 minutes under load.
This procedure is run as an "OK" Load
test, determining "OK" Load as in ASTM
Test D 2782 except utilizing the following
load increments:
a. "OK" Load <20 lb.: Determine "GK"
Load to the nearest 1 lb.
b. "OK~ Load >20 lbs.: Determine ~OK"
Load using standard load increments
as described in ASTM Test D 2782.
The results of various dithiophosphate salts
according to the present invention are set forth in
Table IV.
~7~
-30-
TA~LE IY
TIMKEN EVALUATION OF AROMATIC ZINC
DI~OPHOSPHATES AT 0.05~ P
Alkyl Phenol OK Value Contact Pressure
Example (Mole %) (lb~) (psi)
lB 80% Cresylic Acid 57 20 15,325
20% Heptylphenol
2B 50% p-cresol 25 12,700
50~ m-cresol
3B 100% Heptylphenol 13 7,750
4B 100% Dodecylphenol 15 Scoring
9B 50% Cresylic Acid 33 20 11,500
50% Heptylphenol
~7
-31
As apparent from the above table, composition~
containing Examples lB and 9B made according to t~le
present invention utilizing high and low hydrocarbyl
substituted aromatic alcohols had good load test 'IOK"
values as well as good contact pressures. However,
compositions containing only a high hydrocarbyl
substituted aromatic phosphorodithioic acid salt had
poor values. Specifically, ~xample 3B containing
heptylphenol had an "OK" value of 13 and a contact
pressure of 7,750 psi. Example 4B had an "OK" value of
and actually had scoring damage imparted thereto.
Example 2B which related to an all low but different low
hydrocarbyl substituents in accordance with another
embodiment of the present invention had good test
results. The solubility was good in fully formulated
lubricant compositions.
As previously noted, the compositions of the
present invention are useful as additives for lubricants
and functional fluids. They can be employed in a
variety of lubricants based on diverse oils of
lubricating viscosity, including natural and synthetic
lubricating oils and mixtures thereofO The lubricants
include crankcase lubricating oils for spark-ignited and
compression-ignited internal combustion engines,
---including automobile and truck engines, two-cycle
engines, aviation piston engines, marine and railroad
diesel enyines, and the likeD Also contemplated are
lubricants for gas engines, stationary power engines and
turbines and the like. Transaxle lubricants, gear
lubricants, metal-working lubricants and other
lubricating oil and grease compositions, as well as
functional fluids such as hydraulic fluids and automatic
transmission fluids, benefit from the incorporation
therein of the compositions of the present invention.
Natural oils include animal oils and vegetable
oils (e.g., castor oil, lard oil) as well as liquid
petroleum oils and solvent-treated or acid-treated
-32-
mineral lubrica~ing oils of the para~finic, naphthen~c
or mixed paraffinic-naphthenic types. ~ils of lubrica-
ting viscosity derived from coal or shale oil can also
be included as the base oil.
Synthetic lubricating oils include hydrocarbon
oils and halosubstituted hydrocarbon oils such as
polymerized and interpolymerized olefins ~e.g.,-
polybutylenes, polypropylenes, propylene-isobutylene,
copolymers, chlorinated polybutylenes, etc.); poly(l-
hexenes), poly(l-octenes), poly(l-decenes), etc. and
mixtures thereof; alkylbenzenes (eOg.~ dodecylbenzenes,
tetradecylbenzenes, dinonylbenzenes, di(2-ethylhexyl)
benzenes, etc.); polyphenyls (e.g., biphenyls,
terphenyls, alkylated polyphenyls, etc.); alkylated
diphenyl ethers and alkylated diphenyl sulfides and the
derivatives, analogs and homologs thereof and the like.
Alkylene oxide polymers and interpolymers and
derivatives thereof where the terminal hydroxyl groups
have been modified by esterification, etherification,
etc. constitute another class of known synthetic oils.
These are exemplified by the oils prepared through
polymerization of ethylene oxide or propylene oxide, the
alkyl and aryl ethers of these polyoxyalkylene polymers
(e.g. methylpolyisopropylene glycol ether having an
average molecular weight of 1000, diphenyl ether of
polyethylene glycol having a molecular ~7eight of
500~1000, diethyl ether of polypropylene glycol having a
molecular ~eight of 1000~1500, etc.) or mono- and
polycarboxylic esters thereof, for example, the acetic
acid esters, mixed C3-Cg fatty acid esters, or the
C13 Oxo acid diester of tetraethylene glycol.
Another suitable class of synthetic lubricating
oils comprises the esters of dicarboxylic acids (e~g.,
phthalic acid, succinic acid, alkyl succinic acids and
alkenyl succinic acids, maleic acid, azelaic acid,
suberic acid, sebacic acid, fumaric acid, adipic acid,
linoleic acid dimer, malonic acid, alkyl malonic
~7~3
-33-
âcids~ alkenyl malonic acids, etc.) with a variety of
alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl
alcohol, 2-ethylhexyl alcohol, ethylene glycol, di-
ethylene glycol monoether, propylene glycol, etc.).
Specific examples of these esters include dibutyl
adipate, di-(2~ethylhexyl) seb`acate, di-n-hexyl
fumarate, dioctyl sebacate, diisooctyl azelate, di-
isodecyl acelate, dioctyl phthalate, didecyl phthalate,
dieicosyl sebacate, the 2-ethylhexyl diester of linoleic
acid dimer, the complex ester formed by reacting one
mole of sebacic acid with two moles of tetraethylene
glycol and two moles of 2-ethylhexanoic acid, and the
like.
Esters useful as synthetic oils also include
those made from Cs to C12 monocarboxylic acids and
polyols and polyol ethers such as neopentyl glycol,
trimethylolpropane, pentaerythritol, dipentaerythritol,
tripentaerythritol, etcO
Silicon~based oils such as the polyalkyl-,
polyaryl-, polyalkoxy-, or polyaryloxy-siloxane oils and
silicate oils comprise another class of synthetic oils
(e~g., tetraethyl silicate, tetraisopropyl silicate,
tetra-(p-tertbutylphenyl) silicate, hexa-(4-methyl-
2-pentoxy)-disiloxane, poly(methyl) siloxanes, poly
~methylphenyl)siloxanes, etc.). Other synthetic oils
include liquid esters of phosphorus-containing acids
(e.g., tricresyl phosphate, trioctyl phosphate, diethyl
ester of decylphosphonic acid, tc.), polymeric tetra-
hydrofurans and the like.
Unrefined, refined and rerefined oils (and
mixtures of each with each other) of the type disclosed
hereinabove can be used in the lubricants and functional
fluids of the present invention. Unrefined oils are
those obtained directly from a natural or synthetic
source without further purification treatment. For
example, a shale oil obtained directly from retorting
-34-
operations, a petroleum oil obtained directly fr~m
distillation or an ester oil obtained directly from an
esterification process and used ~ithout further
treatment would be an unrefined oil. Refined oils are
similar to the unrefined oils except they have been
further treatment in one or more purification steps to
improve one or more properties. Many-such purification
techniques are known to those of skill in the art such
as solvent extraction, acid or base extraction, filtra-
tion, percolation, etc. Rerefined oils are obtained by
processes similar to those used to obtain refined oils
applied to refined oils which have been already in
service. Such rerefined oils are also known as
reclaimed or reprocessed oils and often are additionally
processed by techniques directed to removal of spent
additives and oil breakdown products.
Generally, the lubricants and functional fluids
o~ the present invention contain an amount of the com-
positions of this invention sufficient to provide it
with antioxidant and/or anti-wear properties. Normally
this amount will be about 0.25 percent to about 10
percent, preferably about 0.4 percent to about 7.5
percent of the total weight of the fluid.
The invention also contemplates the use of
other additives in combination with the compositions of
this invention. Such additives include, for example,
detergents and dispersants of the ash-producing or
ashless type, corrosion- and auxiliary oxidation-
inhibiting agents, pour point depressing agents,
auxiliary extreme pressure agents, color stabilizers and
anti-foam agents~
The ash-producing detergents are exemplified by
oil-soluble neutral and basic salts of alkali or
alkaline earth metals with sul~onic acids, carboxylic
acids, or organic phosphorus acids characterized by at
least one direct carbon-to-phosphorus linkage such as
those prepared by the treatment of an olefin polymer
(e.g., polyisobutene having a molecular weight o~ 1000~
with a phosphorizing pentasulfide, phosphorus tri-
chloride and sulfur, white phosphor~s and a sulfur
halide, or phosphorothioic chloride. The most commonly
used salts of such acids are those o~ sodium, potassium,
litium, calcium, magnesium, strontium and barium.
The term "basic salt~ is used to designate
metal salts wherein the metal is present in stoichio-
metrically larger amounts than the organic acid
radical. The commonly employed methods for preparing
the basic salts involve heating a mineral oil solution
of an acid with a stoichiometric excess of a metal
neutralizing agent such as the metal oxide, hydroxide,
carbonate, bicarbonate, or sulfide at a temperature
above 50C and filtering the resulting mass. The use of
a "promoter" in the neutralization step to aid the
incorporation of a large excess of metal likewise is
known. Examples of compounds useful as the promoter
include phenolic substances such as phenol, naphthol,
alkylphenol, thiophenol, sulfurized alkylphenol, and
condensation products of formaldehyde with a phenolic
substance; alcohols such as methanol, 2-propanol, octyl
alcohol, cellosolve, carbitol, ethylene glycol, stearyl
alcohol, and cyclohexyl alcohol; and amines such as
aniline, phenylenediamine, phenothiazine, phenyl-beta-
naphthylamine, and dodecylamine. A particularly
effective method for preparing the basic salts comprises
mixing an acid with an excess of a basic alkaline earth
metal neutralizing agent and at least one alcohol
promoter, and carbonating the mixture at an elevated
temperature such as 60-200C.
-36-
Ashless detergents and dispersants are r SO
called despite the fact that, depending on its
constitution, the dispersant may upon combustion yield a
non-volatile material such as boric oxide or phosphorus
pentoxide; however, it does not ordinarily contain metal
and therefore does not yield a metal-containing ash on
combustion. Many types are known in the art, and any of
them are suitable for use in the lubricants of this
invention. The following are illustrative:
(1) Reaction products are carboxylic acids (or
derivatives thereof) containing at least about 34 and
preferably at least about 54 carbon atoms with nitrogen-
containing compounds such as amine, organic hydroxy
compounds such as phenols and alcohols, and/or basic
inorganic materials. Examples of these "carboxylic
dispersants" are described in British Patent 1,306,529
and in many U.S. patents including the following:
3,163,603 3,351,552 3,541,012
3,184,474 3,381,022 3,542,678
3,215,707 3,3g9,141 3,542,680
3,219,666 3,415,750 3,567,637
3,271,310 3,433,744 3,574,101
3,272,746 3,444,170 3,576,743
3,281,357 3,44~,048 3,630,904
3,306,gO8 3,448,049 3,632,510
3,311,558 3,451,933 3,632,511
3,316,177 3,454,607 3,697,428
3,340,281 3,467,668 3,725,441
3,341,542 3,501,405 Re 26,433
3,346,493 3,522,179
~ (2) Reaction products of relatively high
molecular weight aliphatic or alicyclic halides with
amines, preferably polyalkylene polyamines. These may
t.~
-37-
be characterized as "amine dispersants'1 and examplRs
thereof are described ~or example, in the following U.S
patents:
3,275,554 3,454,.555
3,438,757 3,565,804
(3) Reaction products of alkyl phenols in
which the alkyl group contains at least about 30 carbon
atoms with aldehydes (especially formaldehyde) and
amines ~especially polyalkylene polyamines), which may
be characterized as "Mannich dispersants". The
materials described in the following U.S. patents are
illustrative:
3,413,347 3,725,480
3,697,57~ 3,726,882
3,725,277
(4) Products obtained by post-treating the
carboxylic, amine or Mannich dispersants with such
reagents as urea, thiourea, carbon disulfide, aldehydes,
ketones, carboxylic acids, hydrocarbon-substituted
succinic anhydrides, nitriles, epoxides, boron copounds,
phosphoruc compounds or the like. Exemplary materials
of this kind are described in the following U.S.
patents:
3,036,003 3,282,955 3,493,520 3,639,242
3,087,936 3,312,619 3,502,677 3,649,229
3,200,107 3,366,569 3,513,093 3,649,659
3,216,936 3,367,943 3.533.945 3,658,836
3,254,025 3,373,111 3,539,633 3,697,574
3,256,185 3,403,102 3,573,010 3,702,757
3,278,550 3,442,808 3,579,450 3,703,536
3,280,234 3,455,831 3,591,598 3,704,308
3,281,428 3,455,832 3,600,372 3,708,522
3~;~
- 38 -
(5) Interpolymers of oil-solubiliziny monomers
such as decyl methacrylate, vinyl decyl ether and high
molecular weight olefins with monomers containing polar
substituents, e.g., aminoalkyl acrylates or acrylamides
and poly-(oxyethylene)-substituted acrylates. ~hese may
be characterized as "polymeric dispersants" and examples
thereof are disclosed in the following U.S. patents:
3,329,658 3,666,730
3,449,250 3,687,849
3,519,565 3,702,300
Auxiliary extreme pressure agents and corrosion-
and auxiliary oxidation-inhibiting agents are exemplified
by chlorinated aliphatic hydrocarbons such as chlorinated
wax; organic sulfides and polysulfides such as benzyl
disulfide, bis(chlorobenzyl)disulfide, dibutyl tetra-
sulfide, sulfurized methyl ester of oleic acid, sulfurized
alkylphenol, sulfurized dipentene, and sul~urized terpene;
phosphosulfurized hydrocarbons such as the reaction
product of a phosphorus sulfide with turpentine or methyl
oleate; phosphorus esters including principally
dihydrocarbon and trihydrocarbon phosphites such as
dibutyl phosphite, diheptyl phosphite, dicyclohexyl
phosphite, pentylphenyl phosphite, dipentylphenyl
phosphite, tridecyl phosphite, distearyl phosphite,
dimethyl naphthyl phosphite, oleyl 4-pentylphenyl
phosphite, polypropylene (molecular weight 500)-
substituted phenyl phosphite, diisobutyl-substituted
phenyl phosphite; and metal dithiocarbamates, such as zinc
dioctyldithiocarbamate and barium heptylphenyl
dithiocarbamate.
,~ ~
.~ .\
;3;~
- 39 -
Pour poink depressants are a particularly usefu]
type of additive o~ten included in the lubricating oils
described herein. The use of such pour point depressants
in oil-based composition to improve low temperature
properties of oil-based composition~ is well known in the
art. See, for example, page 3 of "Lubricant Additives" by
C.V. Smalheer and R. Kennedy Smith (Lezius-~iles Co.
publishers, Cleveland, Ohio, 1967).
Examples of useful pour point depressanks are
polymethacrylates, polyacrylates; polyacrylamides;
condensation products of haloparaffin waxes and aromatic
compounds, vinyl carboxylate polymers; and terpolymers of
dialkylfumarates, vinylesters of fatty acids and
alkylvinylethers. Pour point depressants useful for the
purposes of this invention, techniques for their
- preparation and their uses are described in U.S. Patent
Nos 2,387,501; 2,015,748; 2,655,479; 1,815,022; and
3,250,715.
The metal salt compositions of this invention
can be added directly to the lubricant. When contained in
a lubricant composition, the amount of the metal salt
compositions is such that the amount of phosphorus in said
lubricating composition from about 0.001 to about
0.15 parts by weight per 100 parts by weight of the
lubricant composition. A more desirable amount of
the metal salts of hydrocarbyl substituted aromatic
phosphorodithioic acids is from 0.025 to about 0.1 parts
by weight of the phosphorus in said lubricant
composition. However, they are often diluted with a
substantially inert, normally liquid organic diluent
such as mineral oil, naphtha, benzene, toluene,
xylene, or the like to form an additive concentrate.
These concentrates usually contain from about 3 to about
percent by weight of the metal salts of the present
``
-40-
invention, as set forth in Table V. Additionally, t~e
concentrates can contain one or more additive known in
the art or described hereinabove. The remainder of the
concentrate is substantially inert normally liquid
diluent.
The amount of the metal salts contained in the
lubricant composition is generally a minor amount with a
major amount being the lubricating oil.
~'~ 7 3;~
-41-
TABLE V
~oncentrat~ A
Product of Example lD 34 ~ 5% by weight
Mineral Oil 13.8% by weight
Basic Calcium Petroleum Sulfonate 51~7~/o by wei~ht
Concentrate ~
Product of Example lB 10% by weight
Mineral Oil 90% by weight
~a~
Product of Example 2B 15~ by weight
Mineral Oil 50% by weight
Polybutenyl Succinic Anydride-
Ethylene Polyamine
Reaction Product 35% by weight
-42-
While in accordance with the patent statutes a
best mode and pre~erred embodiment have been set forth,
it is to be understood that various modifications
thereof will become apparent to those skilled in the art
upon reading of the specification.~ Therefore, it is to
be understood that the invention disclosed herein is
intended to cover such modifications as fall within the
scope of the attached claims.
