Note: Descriptions are shown in the official language in which they were submitted.
1(~6alC~4;~
~ACKGF~OUND OF_T_E_INVFN~ION
2 Fl_ld__f_the_I_V_ntl_a
3 This invention r~lates to new lubricating oil
4 additives, processes for preparing them, and lubricating oil
additive concentrates and lubricating oil compositions containing
6 thes~ additives. More particularly, this invention relates to
7 oil-soluble Group I or Group II metal or lead hydrocarbyl
8 ethrlsulfonates.
9 Lubricatin~ oil compositions, particularly for use in
internal combustion enqines, perform many functions besides
11 simply lubricating relatively moving parts. Modern, highly
12 compounded lubricatinq oil compositions provide anti-wear, anti-
13 oxidant, extreme-pressure and anti-rust protection and maintain
14 the cleanliness of the engine.
De_crl~tin__f_t he _PEi---Art
16 Mixon et al, U.S. 2,367,468, teach reacting an olefin
17 polYmer, preferably having a molecular weigh~ of 500 t~ 3000,
18 with chlorosulfonic acid and then forming the metal salt.
19 Knowles et al, U.S. 2,683,161, teach stabilization by
the heatinq to 110 to 300C of arylalkane sulfonates of the
21 formula RI-(5O2-O-R2)x. The sulfona~es are prepared from a
22 saturated aliphatic hydrocarbon which has been reacted with: (1)
23 chlorine and sulfur dioxide; and (2) a phenol. Rl is an
24 aliphatic radical derived from a petroleum hydrocarbon containing
saturated branched-chain hydrocarbons, preferably of from 6 to 24
26 carbon atoms. These compounds are proposed for use as
27 plasticizers and functional fluids.
28 Distler, U.S. 3,133,948, teaches preparinq
29 vinylsulfonates of aromatic hydroxy compounds by reacting carbyl
sulfate ~ith an aromatic hydroxy compound in an aqueous alkaline
31 medium at a pH between 7.5 and 11. 5 to yield an aryl
101600~Z
vinylsulfonate. Suitable aromatic hydroxy compounds lnclude ortho- and
para~chlorophenol. Carbyl sulfate is prepared from the reaction of ethylene
wlth sulfur trioxide or oleum.
Klass et al, United States 3,158,639 state that carbyl sulfate has
been known since 1836 and teach that it may be prepared by reacting ethylene
with sulfur trioxide at a 2:1 mol ratio either in solution or in the vapor
phase, usually at room temperature or lower to avoid charring.
Friedrichsen and Distler, United States 3,205,249, disclose aryl
esters of unsaturated sulfonic acids prepared by reacting an olefin contain-
ing at least 1 methyl and~or methylene group adjacent to the double bond link-
age with an aryl vinylsulfonate at temperatures between 100-300C. Suitable
oleflns contain between 3 and 20 carbon atoms. These compounds are proposed
for use as plasticizers and textile auxiliaries.
British 1,246,545 teaches a sulfonated olefin prepared by halo-
genating an olefin, dehydrohalogenating to a conjugated diene, sulfonating
by conventional methods and, optionally, neutralizing with an alkaline earth
; metal.
SUMMARY OF THE INVENTION
This invention comprises oil-soluble Group I and Group II metal
and lead salts of substantially saturated aliphatic hydrocarbylethylsulfonic
acids in which the substantially saturated hydrocarbyl substituent contains
at least 25 carbon atoms~ These salts have excellent detergency and
dispersancy properties in lubricating oils.
The hydrocarbyl substituent preferably contains from about 25
to about 350 carbon atoms, most preferably 25 to 200 carbon atoms.
According to a preferred embodiment the present invention prGvides
an oll-soluble Group I or Group II metal or lead salt of a sulfonic acid
of the formula: Rll
H2C CH2 2 ~I)
or Rll
H3C - CH - SO2 - O - H
~ - 3 -
106iO04Z
wherein R is a substantlally saturated a]iphatic hydrocarbyl g~oup contain-
ing about 25-350 carbon atoms and 0-3 sltes of olefinic unsaturation.
Preferably Rl is a substantially saturated aliphatic hydrocarbyl containing
50 - 200 carbon atoms and 0 - 2 sites of olefinic unsaturation.
According to another aspect of the present invention there is
provided a process for preparing an oil-soluble Group I or Group II metal
salt of a substantially saturated aliphatic hydrocarbyl ethylsulfonic acid,
in which the substantially saturated aliphatic hydrocarbyl substituent contains
at least 25 aliphatic carbon atoms, comprising combining an arylester of the
substantially saturated aliphatic hydrocarbyl ethylsulfonic acid with a
Group I or Group II metal oxide or hydroxide.
Preferably, the salts can be prepared by reacting the aryl ester
`~ of a substantially saturated hydrocarbyl ethylsulfonic acid with from about
1 to 30 equivalents per equivalent of sai~ ester of a Group I or Group II
metal oxide or hydroxide.
According to a preferred embodiment the present invention provides
a process for preparing an oil-soluble Group I or Group II metal salt of
a sulfonlc acid of the formula:
.1
H2~ ~ CH2 - SO2 - O - H (I)
or
Rr
H3C - CH - SO2 - O- H (II)
wherein R represents a substantially saturated aliphatic hydrocarbyl contain-
ing about 25-350 aliphatic carbon atoms and 0-3 sites of olefinic unsaturation
comprising combining an aryl ester of a substantially saturated hydrocarbyl
ethylsulfonic acid with a Group I or Group II metal oxide or hydroxide.
Pre~erably, Rl is a substantially saturated hydrocarbyl containing 50-200
carbon atoms and 0-2 sites of olefinic unsaturation.
The oil-soluble sulfonates of this in~ention can also be prepared
by~ f~rst preparlng a neutral Group I metal salt of the sulfonate and then
conVerting this ~aterial by metathesis into the Group II metal or lead
sulfonate.
~ 3a -
1016004~
More particularly, the present invention also provides a process
for preparing an oil-soluble Group II metal or lead salt of a substantially
saturated aliphatic hydrocarbylethylsulfonic acid, in which the substantially
saturated hydrocarbyl contains at least 25 aliphatic carbon atoms, comprising
1. contactlng an aryl ester o the substantially saturated hydrocarbyl-
ethylsulfonlc acid with a Group I metal oxide or hydroxide to form a firs~
reaction product, and
2 contacting the first reaction product with a water-soluble Group
II metal or lead salt to form the Group II metal or lead salt of the sub-
stantially saturated hydrocarbylethylsulfonic acid.
Included with this invention are the neutral metal salts (asdescribed above) overbased with a Group II metal carbonate and a method for
the preparation of these salts.
More particularly, the present invention provides an oil-soluble
; Group II metal carbonate overbased Group I or Group II metal or lead salt
of a sulfonic acid of the formula:
Rl
; H2 ~ ~ - CH2 - S02 - OH (I)
or Rl
H3C - CH - S02 - OH (II)
wherein R is a substantially saturated aliphatic hydrocarbyl group contain-
ing about 25-350 carbon atoms and 0-3 sites of olefinic unsaturation.
The present invention also provides a concentrated lubricating oil
additi~e composition comprising
; ~a) 85%-15% weight of an oil of lubricating viscosity, and
(b) 15%-85% weight of an oil-soluble Group I or Group II metal or lead
salt of a substantially saturated aliphatic hydrocarbylethylsulfonic acid in
which the substantially saturated hydrocarbyl group contains at least 25
aliphatic carbon ato~s.
The present invention further provides a co~position comprising:
a ~ajor a~ount of an oil of lubricating viscosity, and a detergent-dispersant
a~ount up to 15% b~ weight of an oil-soluble Group I or Group II metal or
004~
lead salt of a substantially saturated aliphatic hydrocarbyl ethylsulfonic
acid in which the substantially saturated hydrocarbyl group contains at
least 25 carbon atoms.
The predominant organic group believed to be formed from the
sulfonate ester group and the basically reacting Group I and Group II metal
and lead compounds is a metal sulfonate. Throughout this discussion, the
reaction products obtained as described above will be generically described
as metal sulfonates.
The metal sulfonates of this invention are lubricating oil
additives ha~lng excellent detergent and dispersant properties. They also
aid in preventing ~arnish. They are prepared from sulfonate esters which are
obtained from materials synthesized from readily available, inexpensive raw
materials.
DETAILED DESCRIPTION OF THE INVENTION
The oil-soluble Group I and Group II metal or lead salts of
substantially saturated aliphatic hydrocarbyl ethylsulfonic acids, the
substantially saturated hydrocarbyl substituent containing at least 25
aliphatic carbon atoms, of this invention are prepared by forming the metal
salt of an aryl ester of the formula:
,,
.
10f~004;~
~ I
3 H~C - CH7 - SO~ - O - Aryl (I)
4 or
S Rl
7 HlC - CH - SO~ - 0 - ~ryl (II~
8 where R' is a substantially saturated aliphatic hydrocarbyl
9 substituent containing enough carbon atoms to make the sulfonate
oil soluble.
11 Generally Rl will contain about 25 to about 350 carbon
12 atoms, preferably from about 25 to about 300 carbon atoms, and
13 more preferably frcm about 50 to about 200 carbon atoms.
14 The hydrocarbyl substituent is substantially saturated.
By ~substantially saturated" is meant ~hat at least about 95b of
16 the total number of carbon-to-car~on covalent linkages are
17 saturated linkages. An excessive proportion of unsaturated
18 linkaqes makes the molecules suscepti~le to oxidation,
19 deqradatlon, and polymerization. This makes the products
unsuitable for many uses in hydrocarbon oils.
21 The substantially saturated hydrocarbyl substituent may
22 cont~in polar substituents as long as they are present in such
23 minor porportions that they do not significantly alter the
24 hydrocarbon character of the hydrocarbyl group. Such polar
substituents are exemplified by chloro, keto and alkoxy. It is
26 preferred that these groups not be present. The upper limit on
27 thes~ polar sub~tituents in the hydrocarbyl group is about 10% by
28 weight.
29 The substantially saturated hydrocarbyl substituent is
deri~ed primarily from hiqh-molecular-w2ight, substantially
31 saturated petroleum fractions and substantially saturated olefin
32 polymers, particularly polymers of monoolefins having from 2 to
33 about 30 carbon atoms. Espec1ally useful polymers are the
~060~42
1 polymers of 1-monoolefins such as ethylene, propene, 1-butene,
2 isobutene, 1-hexene, 1-octene, 2-methyl-1-heptene, 3-cyclohexyl-
3 1-butene, and 2-~ethyl-5-propyl-1-hexene. Polymers of medial
4 olefins, i.e., olefins in which the olefinic linkage is not at
the terminal position, are also useful. Such olefins are
6 illustrated by 2-butene, 3-pentene, and 4-octene.
7 Also useful are interpolymers of olefins such as those
8 illustrated above with other interpolymarizable olefinic
9 substances such as other 1-olefins, aromatic olefins, cyclic
olefins, and polYolefins. SUCh interpolymers include, for
11 example, those prepared by polymerizinq isobutene with styrene,
12 isobutene with butadiene, propene with isoprene, ethylene with
13 piperylene, ethylene with propene, isobutene with chloroprene,
14 isobutene with p-methyl styrene, 1-hexene with 1,3-hexadiene, 1~
octene with 1-hexene, 1-heptene with 1-pentene, 3-methyl-1-butene
16 ~ith 1-octene, 3,3-dimethyl-1-pentene with 1-hexene, and
17 isobutene with styrene and piperylene.
1fl The relative proportions of the monoolefins to the
19 other monomers in the interpolymers influence the stability and
oil solubility of the final compositions. To promote oil
21 solubility and stability, the interpolymers shoulA be
22 substantially aliphatic and substantially saturated, i.e., they
23 should contain at least about 80%, preferably about 95~, on a
24 weight basis, of units derived from the aliphatic monoolefins and
no mors than about 5% of olefin linkages based on the total
26 number of carbon-to-carbon covalent linkages. In most instances
27 there will be about one olefinic linkage per molecule. The
28 percentage of olefinic linkages is preferably less than about 2
29 of the total number of carbon-to-carbon covalent linkagesO
Specific examples of such interpolymers include
31 copolymers of 95~ (by weight) of isobutene with 5S styrene,
1060042
1 terpolymer of 98~ of isobutene with 1~ of ~iperylene and 1~ of
2 chloroprene, terpolymer of 95% of isobutene ~ith 2% of 1-butene
3 and 3~ of 1-hexene, terpolymer of 60% of isobutene with 20~ of 1-
4 pentene and 20~ of 1-octene, copolymer of 80% 1-hexene and 20~ of
1-heptene, terpolymer of 90~ of isobutene with 270 of cyclohexe~e
6 and 8~ of propene, and copolymer of 80h of ethylene and 20% of
7 propene.
8 The aryl sulfonates of formul~s I and II are prepared
9 by adductinq an aryl vinylsulfonate to a hydrocarbon from the
1~ sources mentioned above. This adduction is carried out using
11 conventional techniques such as those used to adduct maleic
12 anhydride to hydrocarbon substituents in preparing hydrocarbyl
13 succinic anhydrides. The arvl substituent is not displaced
14 during the adduction reaction.
In one adduction method, the hydrocarbyl substituent
16 source is charged to the reaction vessel and heated with
17 stirrinq. The aryl vinylsulfonate is added to the reaction
18 vessel and the reaction mass is heated to the reaction
19 temperature, qenerally about 100-300C, preferably 150-250C.
Usually the reaction is completed about 1 to about 48 hours, or
21 pref~rably from a~out 2 to about 24 hours at the preferred
22 reaction temperatures. The reactivity of the hydrocarbyl
23 substituent source in the adduction reaction can often be
24 enhanced if it is first chlorinated. For example, an excellent
hydrocarbYl substituent source is polyisobutene. In the
26 adduction reaction, polyisobutenyl chloride reacts faster and at
27 lower temperatures.
2fl The adduct can be purified by conventional methods.
29 For example, the lower boiling impurities, such as excess
phenylvinylsulfonate, are removed by distillation or co-
31 distillation ~ith a hydrocarbon solvent of intermediate boillng
,
-- 7 --
~06~04~
1 ranq~. A typical solvent is a solvent-refined neutral oil. The
2 distillation process is usually carried out at a reduced
3 pressure. The adduct is further purified by diluting it with an
4 aliphatic hydrocarbon solvent and filterin~ to remove any
resinous by-products or polymeric material. Finallyt the solvent
6 is remoYed by stripping to yield the pure product.
7 In formulas I and II, "aryl" is an aryl radical or a
8 substituted aryl radical. The aryl radical is derived from an
9 aromatic hydroxy compound which can react with carbyl sulfate to
form an aryl vinylsulfonate. The aryl vinylsulfonate is
11 converted ~o the compounds of formulas I and II as described
12 above.
13 Suitable aromatic hydroxy compounds contain at least
14 one carbocyclic aromatic ring and at least one hydroxy group
attached directly to the carbocyclic aromatic ring. The aromatic
16 ring may be substituted with mild electron withdrawing groups
17 which promote its reactivity with the carbyl sulfate. Preferred
18 electron withdrawing groups are halo, especially chioro and
19 bromo. A particularly useful group is a single chloro group
located either ortho or para to the hydroxy group. The aromatic
21 rin~ may also be substituted with mild electron-donating groups
22 such as methyl and ethyl.
23 Preferred aromatic hydroxy compounds contain 1 to 3
24 carbocyclic aromatic rings and 1 to 3 hydroxy groups. ~f the
aromatic hydroxy compound'contains more than 1 aromatic ring, the
26 rinqs may be condensed'~as in naphthol), linked by single bond
27 (as in diphenol) or linked via a short-chain bridge ~as in
2fl diphenolmethane~.'
29 The most preferred'aromatic compounds are those of the
formula:
~0~0042
y ~ ~X
m \ ~ n
OH
1 wherein X is halo, Y is C~-C6 alkyl, n is zero or 1-2, and m is
2 zero, 1 or 2.
3 Suitable aromatic hydroxy compounds include phenol, the
4 cresols, the xylenols, p-tertiary butylphenol, nonylphenol,
dodecylphenols, o-chlorophenol, p-chlorophenol, 4-chloro-2-
6 methylphenol, ortho- and meta-methyl-4,4'~dihydroxydiphenyl,
7 4,4'-dihydroxydiphenylmethane, 2,2-bis-(4'-hydroxyphenyl)propane,
8 bis-(4'-hydroxyphenyl)sulfone, resorcinol, 3-cyanophenol, 4,4'-
9 dihydroxydiphenyl sulfoxide, 3-iodophenol, octadecylphenols, 4-
cyclohexylphenol, 4-cyclododecylphenol, 4-dibutylaminophenol, 4-
11 (N-methyl-N-ethyl)aminophenol, 3-methoxyphenol and 4-
12 butoxyphenol.
13 The aryl ester of ~inylsulfonic acid can be prepared by
14 several available techniques. U.S. 3,121,730 teaches reacting a
beta-chloroethanesulfonyl chloride with phenol in an aqueous
16 medium at a pH of between 7.5 and 11.5. The reaction proceeds
17 with a loss of 2 mols of hydrogen chloride to yield phenyl
18 vinylsulfonate. U.S. 3,133,~48 teaches reacting carbyl sulfate
19 with an aromatic hydroxy compound in an aqueous alkaline medium
at a pH between 7.5 and 11.5 to yield a phenyl vinylsulfonate.
21 Another more convenient method does not allow the
22 carbyl sulfate to solidify after it is prepared because carbyl
23 sulfate is difficult to use after it has solidified. In this
24 method the carbyl sulfate is prepared by reacting ethylene with
sulfur trioxide at temperatures above the melting point of carbyl
26 sulfate, about 110~-180C, preferably about 150-160C. The
27 molten carbyl sulfate is immediately introduced into an aqueous
28 caustic solution of the aromatic hydroxy compound. The carbyl
_ g
10~;0~4Z
1 sulfate reacts with the aromatic hydroxy compound to yield the
2 aryl ester of vinylsulfonic acid plus sodium sulfate. Preferably
3 the aqueous solution is maintained between 0C and 25C and at a
4 pH of 9 to 11. After the sulfonate ester is isolated from the
aqueous solution, it can be converted to the adduct as described
6 above.
7 The carbyl sulfate and the aroma'ic hydroxy compound
8 are usually reacted in e~uivalent quantities, i.e., a molar ratio
9 of about 1:1 phenol/carbyl sulfate molar ratio for monohydric
phenols and about a 1:2 phenol/carbyl sulfate molar ratio for
11 dihydric phenols. Since the carbyl sulfate tends to hydrolyze in
12 an aqueous solution, an excess must be added in order to obtain
13 1:1 equivalent ratio ~ith the aromatic hydroxy compound.
Tke_Met al-s al_s
The metal sulfonates are-prep~red using any Group I and
16 Group II metals or lead compound which forms a salt with the
17 sulfonic acid moiety and which yields a salt useful as a
18 deter~ent in lubricating oil compositions. Preferably, the Group
19 I metal compounds are lithium, sodium and potassium compounds and
the Group II metal compounds are magnesium, calcium, strontium,
21 barium and zinc. The lead compound must be in the +2 valence
22 state, i.e., Pb++. More preferably, the Group I metal compounds
23 are sodium and potassium compounds and the Group II metal
24 compounds are magnesium, calcium and barium compounds.
The Group I and Group II metal salt of this invention
26 can be prepared by a variety of means. One method is combining
27 the metal hydroxide or oxide with the aryl ester of the hydro-
28 carbyl ethylsulfonic acid described above. This is generally
29 carried out in the presence of a hydroxylic promoter such as 1,3-
propanediol, 1,4-butanediol, diethylene glycol, butyl cellosolve,
31 propylene qlycol, 1,4-butyleneglycol, m~thyl carbitol,
32 ethanolamine, diethanolamine, N-methyl-diethanolamine, dimethyl
, ., ~
-- 1 0
~ ~Trademark
106004Z
formamide, N-methyl acetamide, dimethyl acetamide~ and especially
water, methanol or ethylene glycol. An inert solvent is usually
used and the reaction mixture is heated. The metal oxide or
hydroxide hydrolyzes the ester group to yield the metal
sulfonate. Thereafter, the promoter, solvent and by-products can
be removed to yield the metal sulfonate.
Under certain circumstances, it may be more convenient
to prepare a Group I metal salt of the sulfonate and convert this
material by metathesis into the Group II metal or lead sulfonate.
In this method the aryl hydrocarbyl ethylsulfonate is reacted
with a Group I metal oxide or hydroxide, such as sodium or
potassium hydroxide. The sodium or potassium sulfonate obtained
can be partially purified by aqueous extractionn Thereafter, the
Group I metal sulfonate is reacted with a Group II metal salt or
a lead salt to form the Group II metal or lead sulfonate. A
suitable Group II metal salt is a halide, particularly a chloride
because of its low cost. A suitable lead compound is lead
nitrate or lead acetate. Typically, the sodium or potassium
sulfonate is combined with an aqueous chloride solution of the
Group II metal or lead salt and stirred for sufficient time to
allow metathesis to occur. The water phase is then removed and
the solvent may be evaporated if desirPd.
If a salt having a completely saturated hydrocarbyl
group is desired, it is necessary to hydrogenate the Group I or
Group II metal or lead sulfonate with hydrogen, using, for
example, a conventional noble metal or noble metal oxide
hydrogenation catalyst, such as platinum or platinum oxide.
The sulfonates can be overbased. Overbased materials -
are characterized by a metal content in excess of that which
would be present according to the stoichiometry of the metal
cation and the particular organic compound said to be overbased.
~6~Z
1 Thus an oil-soluble monosulfonic acid neutralized with a Group II
2 oxide or hydroxide, e.g., calcium oxide or hydroxide, produces a
3 normal sulfonate containing one equivalent of calcium for each
4 equivalent of acid. In other words, the normal metal sulfonate
~ will contain one mol of calcium for each two mols of the
6 monosulfonic acid.
7 By applying well-known procedures, "overbased" or
8 "basic" complexes of the sulfonic acids can be obtained. These
9 overbased materials can contain metal m~ny times in excess of
that required to neutralize the acid. These stoichiometric
11 excesses can vary considerably, e.g., from about 0.1 to about 30
12 or more equivalents dependinq upon the reactants, the process
13 conditions, etc.
14 The degree of overbasing can be expressed by several
ways. One method is to describe the "metal ratio". This method
16 describes the ratio of the total chemical equivalents of metal in
17 the product to the chemical equivalents of the compound said to
18 be overbased, based on the known chemical reactivity and
19 stoichiometry of the two reactants. Thus in a normal (neutral)
calcium sulfoante, the metal ratio is 1 and in overbased
21 sulfonate the metal ratio can range from about 1.1 to 30 or more,
22 qenerally from about 5 to 20.
23 Another method of expressing the degree of overbasing
24 is to describe the "base ratio". This method describes the ratio
of chemical equivalents of basic metal to the chemical
2~ e~uivalents of neutral metal. The neutral metal is the metal
27 ~hich ~ould be expected to react with the compound to be
28 overbased, i.e., the metal reguired to neutralize the sulfonate.
29 The basic metal is the metal in excess of the neutral metal,
i.e., it is the metal available to neutralizs acidic combustion
31 products. Thus a normal (neutral) calcium sulfonate has a base
- 12 -
~6~04Z
ratio of 0 and an overbased sulfonate can have a base ratio
2 ranging from about 0.1 to about 30 or more, generally about 4 to
3 about 19.
4 Another method of specifying the degree of overbasing
of dispersants such as the sulfonates is by stating the
6 alkalinity value (AV) of the composition. The method for
7 determininq the alkalinity value of an overbased composi~ion is
8 set forth in AsTn Method D-2896. Briefly, the alkalinity value
9 is stated as the number of milligrams of potassium hydroxide per
qram of composition to which the overbasing is equal. For
11 example, if the composition is overbased to the extent that it
12 has ~he same acid neutralizing capacity per gram as 10 milligrams
13 of potassium hydroxide, the composition lS given an alkalinity
14 value of 10~ The lower limit of alkalinity value is zero for a
neutral sulfonate, with values of 10 to 50 being common for
16 slightly overbased sulfonates. Highly overbased sulfonates have
17 values ranqinq from about 275 to about 400.
18 A discussion of the general method of preparing
19 overbased sulfonates and other overbased products is disclosed in
U.S. 3,496,105.
21 L_kri_atln~_oil_co __ntra_e_
22 Lubricating oil additive concentrates contain from
23 about 85~ to about 15% weight of an oil of lubricating viscosity
24 and from about 15% to about 85% weight of the oil-soluble Group I
and Group Il metal and/or lead sulfonates of this invention. The
26 concentrates contain as much of the oil-soluble sulfonate as is
27 practical, since the concentrates are prepared to reduce shipping
2B costs, stora~e requirements, etc. Typically, the concentrates
29 contain only sufficient diluent to make them easy to handle
during shipping and blending.- Any inert diluent is suitable,
31 preferably an oil of lubricating viscosity is used so that the
- 13 -
1~:)600~Z
1 concentrate may be readily mixed with lubricating oils to prepare
2 lubricatinq oil compositions. SUitable lubricating oils
3 typically have viscosities in the range of from about 35 to about
4 1000 Saybolt Universal Seconds (SUS) at 38C (100F), although
any oil of lubricatinq viscosity can be used.
6 L__rl__tin~ Qil C_mPosltions
7 Lubricatinq oil compositions comprise (a~ an oil of
8 lubricating viscosity, usually in a major amount, and (b) an
9 amount effective to provide detergency tusually a minor amount)
of at least one of the oil-soluble Group I and Group II metal and
11 lead sulfonates of this invention.
12 Suitable lubricating oils are oils of lubricating
13 viscosity derived from petroleum or synthetic sources. The oilc
14 can be paraffinic, naphthenic, halo-substituted hydrocarbons,
synthetic esters, or combinations thereof. Oils of lubricating
16 viscosity have viscosities in the range of 35 to 50,000 Saybolt
17 Universal Seconds (SUS) at 38C (100F), and more usually from
18 about 50 to 10,000 SUS at 38C ~100F). The amount of the oil-
19 soluble Group I and/or Group II metal and~or lead sulfonate which
is incorporated in the lubricating oil composition to provide the
21 amount necessary for detergency varies widely with the particular
22 sulfonate used as well as the use to which the lubricating oil
23 composition is put.
24 In general, the lubricating compositions will contain
from about 0.1~ to about 15X by weight of the oil-soluble metal
26 sulfonate. More usually, the lubricating oil composition of the
27 invention will contain from about 0.5% to about 10% weight of the
28 metal sulfonate and more usually from about 1~ to about 8~ weight
29 of the metal sulfonate.
~he overbased metal sulfonates of this invention can ~e
31 incorporated in lubricating oils to obtain an alkalinity value of
- 14 -
106(~ Z
1 from about 0.1 to about 100, more commonly of from about 2 to
2 about 75, in order to control extreme corrosive wear.
3 These lubricating oil compositions are useful for
4 lubricatinq internal combustion engines. The lubricating oils
not only lubricate the engine but, because of their detergency
6 properties, help maintain a high deqree of cleanliness of the
7 lubricated parts.
8 Other conventional additives which can be used in
9 combination with the metal sulfonates of this invention include
ashless dispersants such as the type disclosed in U.SO 3,172,892,
11 3,219,666 and 3,3~1,022; neutral and basic calcium and barium
12 petroleum sulfonates, corrosion inhibitors, oxidation inhibitors,
13 antifoam agents, viscosity index improvers, and pour point
14 depressants. Typical additives include chlorinated wax,
benzyldisul~ide, sulfurized sperm oil, sulfurized terpene,
16 phosphorus esters, such as trihydrocarbon phosphites, metal
17 dithiocarbamates, such as zinc dioctyldithiocarbamate, metal
18 phosphorodithioates, such as zinc dioctylphosphorodithioate,
19 polyisobutylene having an average molecular weight of 100,000,
etc.
21 EXA~PLES
22 The following examples are included to further
23 illustrate the invention.
24 ~xample 1A - Preparation of
~ _E Ph_ ~l-vinyls-lf--at-
26 A 5-liter flask (the o-chlorophenyl vinylsulfonate
27 reactor) is chargea with 1280 ml of water, 640 ml of 1,2-
28 dichloroethane, 150 ml Of 25~o sodium hydroxide in water, and 350
29 gm ~2.72 mols) of o-chlorophenol. This mixture is stirred and
cooled to 0C in a dry ice-acetone bath. A dropping funnel is
31 charged with 908 q of commercial sulfur trioxide (typically
_ 1 5 _
~06004Z
1 contains 850-8hO q of liquid sulfur trioxide~. Ethylene is
2 introduced to a 500 ml flask (the carbyl sulfate reactor). After
3 the ethylene flow is established, sulfur trioxide is introduced
4 into this reaction vessel from its droppinq funnel. A slight
excess of ethylene is used. The reaction between ethylene and
6 sulfur trioxide takes place rapidly with evolution of heat to
7 yield carbyl sulfate. The reaction vessel warms to approximately
8 150=170C. At these temperatures, the liquid carbyl sulfate,
9 which has a melting point of about 109-110C, drips into the
stirred cold sodium chlorophenate solution in the 5-liter flask.
11 The carbyl sulfate and sodium chlorophenate react under
12 alkaline conditions (pH 9-11) to yield o-chlorophenyl
13 vinylsulfonate and sodium sulfate.
14 After all the sulfur trioxide has been added, the
reaction mixture is stirred for about 30 minutes and then
16 neutralized with concentrated HC1 to pH 5. The mixture is then
17 h~ated to 40C, the organic layer is removed, filtered through
18 Celite*filter aid and stripped to an end point of 100C at 2 to 5
19 mm Hg.
Typical crude yields of o-chlorophenyl vinylsulfonate
21 from a 350 q charge of o-chlorophenol vary from 550 to 615 grams~
22 Typically, the crude product contains less than 1% unreacted o-
23 chlorophenol, and has 15.3%-16.4% sulfur, 15.0~-15.6~ chlorine.
24 Example 1B - Preparation
_ _Ph-nxl-v-nyl-ul-o----
26 Vsinq the procedure of Example 1A, phenyl
27 vinylsulfonate is prepared from 253 ~ of phçnol. Analysis:
28 14.8~,-15.4~ S.
29 Example 2 - Adduction of
----hlor-ph~-yl-vlnyl-ulf-n--e-t--~oly-~ltene
31 9.87 kq (10.39 g mols) of a polybutene havinq a number
32 averaqe ~olecular wei~ht of 950 is charged, under nitrogen, to a
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reaction kettle. The polybutene is heated with stirring to
2 120C. 2.73 kq (12.47 g mols) of o-chlorophenyl vinylsulfonate
3 is added and the reaction mass is heated to 220C with stirring
4 and held at this temperature for 24 hours.
The reaction mass is then cooled to less than 65C and
6 15 liters of methanol are added. The mass is refluxed at
7 approximately 65c for 45 minutes with stirring and still under
8 nitroqen. After coolin~ to room temper~ture, phase separation
9 takes plac~. If phase separation does not occur readily, another
10 4 to 8 liters of methanol can be added.
11 The bottom layer is withdrawn from the reaction kettle
1~ and saved. The top layer is transferred to a storage tank. The -
13 bo~tom layer is returned to the kettle and another 15 liters of
14 methanol are added to the kettle. The reaction mass is heated to
15 reflux for 45 minutes with agitation, then cooled at room
16 temperature and allowed to separate. The bottom layer is
17 withdrawn from the kettle and the top layer is tr~nsferred to the
18 storaqe vessel. The bottom layer is returned to the kettle and
19 the container it was in is rinseZ with 4 liters of hydrocarbon
20 thinner which is added to the kettle. The riser to the condenser
21 is heated to 82C, but cold water is maintained on the heat
22 exchanger. A vacuum is applied to the kettle and the contents
23 are heated to 165C maximum to distill off the thinner and
24 methanol. Tl-e bottoms are cooled to room temperature and
25 transferred to a storage container. Typical analysis %S=1.46-
26 1.54, ~Cl-1.49-1.56.
27 Examp~e 3 - Adduct of polyisobutenyl
28 _hloride_and___l_r_Ph_nYl_V nylsul~_nat_
Example-3A
512 g l0.357 mol~ of a polyisobutenyl chloride (4%w
31 chlorine~ prepared from a polyisobutene having a number average
-- 17 --
~06004Z
1 mole(-ular weiq~t of 1400, and 94 g (0.43 mol) o-chlorophenyl
2 vinylsulfonate are charqed to a 1-liter flask. While maintaining
3 a nitroqen atmosphere, the reaction mixture is heated uith
4 stirrinq at 210C and maintained at that temperature for 7 hours.
16-ml samples are taken at 2, 4 and 7 hours for Hyamine*
6 titr tions after conversion to the potassium salt.
7 The Hyamine*titration is used to determine the amount
8 of anionic detergent in a sample. A known weight of sample is
9 dissol~ed in chloroform and titrated with a dilute aqueous
solution of Hyamine*1622. Acidic methylene blue is used as an
11 indicator. The Hyamine*solution is add2d in suitable increments
12 with 2 minutes of vigorous sbaking after each addition. The hlue
13 color is at flrst concentrated in the lower (chloroform) layer,
14 but gradually appears in the upper (aqueous) layer as the Hyamine
is added. The end point is taken as that point at ~hich the
16 color in the two layers is equal. The millimols of sulfonate per
17 gram of sample are equal to VM/W, where V is the milliliters of
18 Hyamin~ solution, M is the molarity of the Hyamine solution, and
19 W is the qrams of sample.
At the end of 7 hours, the remainder of the reaction
21 mixture (532 q) is coole~ and transferred to a 2-lit~r, 3-neck
22 flask equipped with a stirrer and a thermometer, using S0 ml of a
23 hydrocarbon thinner to flush the reaction flask. To the
24 product/thinner mixture, 800 ml of methanol are added and the
mixture is stirred at reflux (64C) for 45 minutes. An emulsion
26 is obtained which does not break on standing. An additional 200
27 ml of methanol and 200 ml of hydrocarbon thinner are added and
28 the mixture is stirred for 2 minutes. The mixture is then
29 allowed to settle at room temperature for 1.5 hours and the
sup~rnatant liquid (ca. 1100 ml) is decanted. 800 ml of methanol
31 is added to the mixture remaining in the flask and stirred at
32 r~flux (63c) for 45 minutes. Aqain, an emulsion is obtained.
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1 200 ml o~ the tlydro~ar~)oll ttlinner is add~d d nd the mixture is
2 stirre(l ~or 2 minutes. The mixture is then allowed to settle at
3 room temperature for l.S hours and the supernatant liquid (ca.
4 1000 ml) is decanted. The extracted product remaining in the
flask is dissolved in hydrocarbon thinner and transferred to a 1-
6 liter, 3-neck flask with a small amount of solvent; the solvent
7 is stripped off to an end poin~ of 165C at 5 mm Hq to yield 466
8 g of product. Analysis: s, 0.88~v; Cl, 1.19%~.
9 E x a~ e _ 3 B
512 q l0.357 mol) of a polyisobutenyl chloride (4%w
11 chlorine prepared from a polyisobutene havin~ a number average
12 molecular weiqht of 1400), and 97 q (0.43 mol) o-chlorophenyl
13 vinylsulfonate are charged to the flask. The reaction mixture is
14 heated under nitrogen with skirring at 180C for 10 hours. The
off-gas is scrubbed throuqh a sparger into an Erlenmeyer flask
16 containinq 200 ml water. 16-ml samples are withdrawn at 2, 4, 6
17 and 10 hours for Hyamine*titration. The off-gas water trap is
18 re~lac~ each tim~ a sample is taken. The water is titrated to a
19 methyl oranqe end point with 3N-sodium hydroxide solution. The 4
titrations require 100, 32.3, 19 and 20.4 ml, respectively, for a
21 t~tal of 171.7 ml, which is eguivalent to 0.515 mol of sodium
22 hydroxide.
23 The remainder of the reaction mixture (530 g) is
24 transferred to a 2-liter, 3-neck flask using about 50 ml of
hydrocarbon thinner to rlnse the reaction flask. 800 ml of
26 methanol is added to the 3-neck flask and the mixture is refluxed
27 ~ith stirrin~ for 3/4 hour. Complete separation is not obtained
28 when the stirring is stopped. 200 ml of n-hexane is added and
29 the mixture is stirred for 2 minutes. After the mixture settles
at room temperature for 1 hour, approximately 800 ml of
31 supernatant liquid is decanted. 800 ml of methanol is added to
32 the 2-liter flask and the mixture is refluxed for 3/4 hour.
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After standing at room temperature for 1.5 hours, about 900 ml of
2 supernatant liquid is decanted. The mixture remaining in the
3 flask is dissolved in hydrocarbon thinner and transferred to a 1-
4 liter, 3-neck flask. The solvent is stripped off the product to
an end point of 165C at 5 mm Hg to yield ~160 g of product.
6 Analysis: S, 0.99%w, Cl, 1.8496w.
7 Example_3C
8 506 q (0.5 mol) of polybutene chloride (4%w chlorine)
9 prepared from a polyisobutene having a number average molecular
~eiqht of 950 is added to a 1 liter reaction flask under a
11 nitrogen atmosphere~ 142 9 (0.65 mol) of o-chlorophenyl
12 vinylsulfonate is then added. The react.ion mass is heated under
13 nitroqen with stirring at 210C for 7 hours. 16-ml samples are
14 withdrawn at 2, 4 and 7 hours for Hyamin~ titra+ion. At the end
of the 7-hour reaction period, the remainder of the reaction
16 mixture (569 g) is transferred to a 2-liter, 3-neck flask using
17 about 50 ml of the hydrocarbon thinner to rinse the reaction
18 flask. 800 ml of methanol is added to the flask and the mixture
19 is stirred at reflux (64C) for about 45 minutes. The mixture is
allowed to stand at room temperature for about 3-1/2 hours. Past
21 separatlon is obtained, but only about 700 ml of supernatant
Z2 liquid could be decanted. 800 ml of methanol is added and the
23 mixture is stirred at reflux (64C) for about 45 minutes. The
24 mixture is allowed to stand at room temperature for 1-3~4 hours.
Fast separation is aqain obtained, hut only about 500 ml of
26 supernatant liquid could be decanted. 600 ml of n-hexane is
27 added to the flask and the mixture is stirred for 2 minutes.
28 ~fter settlinq for 1/4 hour, about 550 ml of supernatant liguid
29 is siphoned off. The mixture remaining in the flask is
transferred to a 1-liter, 3-neck flask using a small amount of n-
31 hexane to rinse the flask. The solvent is removed by stripping
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to 190C at 5 mm l~q to yield 475 g of product. Analysis: S,
2 1.80~2~; Cl 2.16%w.
3 Example 4
4 Pr P3ratio__of_s__l___sulfonat_
A 1-liter, 3-neck flask is charged with 210 g (ca. 0.1
6 mol~ of o-chlorophenyl polyisobutenylethylsulfonate in which the
7 polyisobutenyl qroup has d number average molecular weight of
about 950. 200 ml of an inert hydrocarbon thinn~r are added and
9 the sulfonate and the solvent are stirred to mix them. ~lith
stirring an aqueous solution of 11 g (0.27 mol) of sodium
11 hydroxide in 15 ml of water is added and the reaction mass is
12 heated at 120C for 1.5 hours. The reaction mass is allowed to
13 cool and to settle overnight and then is filtered through
14 Hyflosupercel* (diatomaceous earth).
The filtrate is transferred to a 2-liter separatory
16 funnel, using 200 ml of the thinner as ~ rinse to insure complete
17 transfer. 300 ml of 2-butanol and 300 ml of water are added and
18 the contents of the funnel are mixed +horoughly. The contents of
19 the funnel are allowed to settle for one-half hour and the bottom
20 layer is drained off (ca. 260 ml). The nonaqueous phase
21 remaining in the funnel is washed four times with approximately
22 600 ml of aqueous sodium chloride solution. The sodium chloride
23 solution is used because water alone did not phas~-separate well
24 enough. The hydrocarbon phase is stripped of the butanol and any
entrained water to an end point of 190~C at about 200 mm Hg.
26 The stripped product is cooled and 700 ml of hexane is
27 added. The resulting mixture is filtered through Hyflosupercel.
28 The filtrate is stripped free of solvent to 200C at 5 mm Hg.
29 194 g of product havlng a slight haze are recovered. 80 g of a
30 neutral solvent-refined lubricating oil having a viscosity of 100
31 SUS at 100F (38C) is added. This mixture is heated to 150C
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1 wit.h ~.tirrinq to homogenize and then filtered throuqh
2 Hyflosupercel*to yield a clear product. The product is analyzed
3 with the following results: Na, 0.66%w; s, 0.96~w; Cl, 0.02~.
Example 5 - Preparation of
S calcium sulf__ate by m_t_the_i_
6 To a S-liter flask, 1060 g of o-chlorophenyl
7 polyisobutenylethylsulfonate having a number average molecular
8 ~eiqht of 950 and 1000 ml of an inert hydrocarbon thinner are
9 added. Thereafter, 45 g of sodium hydroxide in 70 ml of water
are added. With stirring the temperature is raised to 100C and
11 maintained there for two hours. After cooling to 95C, a
12 solution of 156 ~ of calcium chloride in 1000 ml of water is
13 added. The reaction mass is stirred for 1 hour at 85C.
14 The reaction mass is transferred to two four-liter
separatory funnels and to each is added 750 ml of 2-butanol. The
16 aqueous phase is drained off the bottom, the hydrocarbon phases
17 are transferred to two five-liter, three-neck flasks and to each
18 is added 80 q calcium chloride in 500 ml water. The mixtures are
19 stirred for 1 hour at 85C and then transferred to two separatory
funnels as before. The aqueous phase is drained off the bottom
21 and ehe hydrocarbon phase is washed again with a mixture of 80 g
22 calcium chloride in 500 ml water and four times with water. The
23 hydrocarbon phase is stripped free of solvent to 175C at 5 mm Hg
24 to yield 1018 q product. To the product is added 509 g of a
neutral solvent-refined lubricating oil having a viscosity of 100
26 SUS at 100F. The mixture is stirred at 150C to homogenize it
27 and is then filtered through Hyflosupercel~ after which it was
28 analyzed with the following results: Ca, 0.56~w; 5, 0.84~w; Cl,
29 0.01~w.
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1 Example 6 - Preparation
2 of_calclum s lfon____d_re_tlY
3 To a two-liter, three-neck flask are added 516 g (0.255
4 mol) of o-chlorophenyl polyisobutenylethylsulfonate in which the
polyisobutenyl has a number average molecular weight of 950
6 (1.58~w sulfur), S00 ml of an inert hydrocarbon thinner, 62 g (1
7 mol) of ethylene qlycol, and 22 g (0.3 mol) of calcium hydroxide~
8 The reaction mass lS heated to 140-145~C for 7.5 hours, diluted
9 with 500 ml of a hydrocarbon thinner and filtered through
Hyflosupercel. The thinner which was added just prior to
11 filtration had a lower boiling point than that used during the
12 reaction. The lower-boiling thinner was distilIed off to a
13 bottoms temperature of 105~ at 200 mm Hq to yield 839 g of
14 solution havinq an AV equal to 23.
Example 7 - Preparation of
16 calclu___ulf_nate_by_m__3_he___
17 To a five-liter, three-neck flask, eguipped as in
18 Example 4, is added 1350 g of phenyl polyisobutenylethyl
19 sulfonate, in which the polyisobutenyl group has a number average
molecular weight of 950, dissolved in 2025 ml of an inert
21 hydrocarbon solvent. A solution of 99 g (1.5 mols) of 85%
22 potassium hydroxide dissolved in 30Q ml of methanol is added.
23 With stirrinq, the methanol is distilled off and the reaction
24 mixture is maintained at 100C for two hours. 800 ml of ~-
butanol is added and the mixture is stirred at 79C for four
26 hours. The reaction mass is divided into two equal parts which
27 are charqed to five-liter, three-neck flasks, each of which is
2~ ~ equipped with a stirrer, thermometer and reflux condenser. To
29 each flask is added 400 ml of 2-butanol, 800 ml of water, and 500
ml of the inert hydrocarbon solvent. The reaction masses are
31 stirred at 80C for one-half hour and then transferred to
32 separatory fbnnels where they are allowed to settle and the water
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1 layers are drawn off. Each of the remaining hydrocarbon phases
2 is transferred to ~eparate five-liter, three-neck flasks equipped
3 as above. Each is stirred three times with a solu~ion of 147 g
4 of calcium chloride dihydrate in 800 ml of ~ater for one hour at
80C and is then water-washed three times with 800 ml of water
6 for 0.75 hour at 80C. After the last water ~ash has been
7 separated from the hydrocarbon layer, the supernatant liguid is
8 filtered throu~h Hyflosupercel. The filtrate is stripped free of
9 the hydrocarbon solvent to 170C bottoms temperature at 5 mm Hg
to yield 1142 g of combined product. The quantity of product was
11 low because some product was lost during the workup. 613 g of a
12 neutral solvent-refined lubricating oil having a viscosity of 100
13 SUS at 100F is added to the product to yield 1755 g of
14 concentrate. T},e concentrate had a slight haze, which was
removed by filterinq through Hyflosupercel. The concentrate is
16 analyzed and found to contain: Ca, 0.65%w; S, 1.07~w; Cl, less
17 than 0.01~w.
ExamP~ 8
19 A one-liter, three-neck flask equipped with a stirrer,
thermometer~ and gas inlet, is charged with 200 g calcium
21 polyisobutenylethylsulfonate in which the polyisobutenyl group
22 has a number averaqe molecular weight of 1400, 500 ml xylene, 50
23 ml methanol, 67 ml 2-eth~lhexanol, and 60 g calcium hydroxide.
24 The mixture is carbonated with 28 g of carbon dioxide at room
2S temperatllre (2Sa-49C) over d period of 45 minutes. The
26 introduction of carhon dioxide is discontinued when the
27 appearance of offqas is observed.
23 The temperature of the reaction mixture is increased to
29 135C to distill off the methanol and water. The mixture is then
cooled, is filtered through ~Iyflosupercel, and is stripped free
31 of solvent to 175C at 5 mm ~g. After a final filtration through
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1 Hyflosupercel, the product contains 8~88% calcium and has a base
2 ratio of 18.7 and AV of 236.
3 Example 9
4 1-G c_t_r~_lla_*t_s
The lubricating oil compositions of this invention are
6 tested in the well-known 1-G Caterpillar*test. In this test, a
7 single-cylinder diesel engine havinq a 5-1f8" bore by 6-1/2"
8 stroke is operated under the following conditions: timing, BT~C
9 8; bra~e mean effective pressure, PSI 141; brake horsepo~er 42;
BTU's per minute 5850; speed 1800 rpm; air boost, 53 inches Hg
11 absolute; air temperature in, 255F (124Cj; ~ater temperature
12 out, 190F (88C); and sulfur in fuel, 0.4%w. At the end of each
13 12 hours of operation, sufficient oil is drained from the
14 crankcase to allow addition of one quart of oil. In the test on
the lubricatinq oil compositions of this invention, the 1-G test
16 is run for the hours shown in Table I. At the end of this
17 period, the en~ine is dismantled and rated for cleanliness. The
1~ ring lands are rated on a scale of 0 to 800, with 0 representing
19 clean and 800 representing black deposits. The ring grooves are
rated on a scale of 0% to 100% qroove fill, with 0 representing
21 clean. The underhead of the piston is rated on a scale of 0 to
22 10, with 0 representinq dirty and 10 representing clean.
23 The base oil used in these tests is a mid-continent
24 base stock SAE 30 oil containing a conventional succinimide
dispersant, a calcium phenate~ and a zinc dithiophosphate. To
26 this base oil is added 10 mmols of the calcium sulfonate to be
27 teste~. For comparison, commercially available calcium
28 sulfonates are tested. The sulfonate designed as A in Table I
29 below is a commercially available calcium sulfonate prepared by
acid-treatinq a neutral sovlent-refined lubricating oil having a
31 viscosity of between 300 and 480 SUS. The sulfonate designated
32 at B in Table I is a commercially available mixture of calcium
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1 sulfonates deriv~d from various soruces such as acid-treated
2 neutral solvent-cefined lubricating oils as well as certain of
3 the hard alkylates produced as by-products in detergent
4 manufacture. The results of testing the lubricating oils of this
invention as ~ell as lubricating oils containing the commercially
6 available sulfonates are set forth in Table I.
7 TABLE I
8 120 Hr l=G Cat_rp_ll_r_Te_t
gsulfona-e Hours Grooves Lan_sUnde_h_3d
A 60 58-4-0.6-0.5 160-310-215 4.B
11 B 60 50-6-0.6-0.7 390-120-515 4.8
12Ex. 5 60 22-4-1.0-0.9 105-20-25 6.6
13Ex. 7 60 27-8-1.0-0.6 165-30-25 5.7
14 120 38-7-2-0.6 168-39-48 4~5
From the data in Table I, it can be seen that the
16 calcium sulfonates of this invention are good detergents in
17 lubricating oil compositions. It should be noted that the
18 lubricatinq oil compositions of this invention provide a
19 significant improvement in the rating of the lower lands of the
pistons compared to the lubricating oils containing the
21 commercially available sulfonate detergents.
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