Lubricants containing amino phenol-detergent/dispersant combinations

Disclosed are combinations of amino phenols, wherein said phenols contain a substantially saturated hydrocarbon substituent of at least 10 aliphatic carbon atoms, and one or more detergent/dispersants selected from the group consisting of (I) neutral or basic metal salts of an organic sulfur acid, phenol or carboxylic acid; (II) hydrocarbylsubstituted amines wherein the hydrocarbyl substituent is substantially aliphatic and contains at least 12 carbon atoms; (III) acylated nitrogen-containing compounds having a substituent of at least 10 aliphatic carbon atoms; and (IV) nitrogen-containing condensates of a phenol, aldehyde and amino compound. Fuels and lubricants containing such combinations as additives are particularly useful in two-cycle (two-stroke) engines.

REFERENCE TO RELATED APPLICATIONS 
Commonly assigned U.S. patent application Ser. No. 622,357, filed Oct. 14, 
1975, in the name of Kirk Emerson Davis and Ser. No. 622,358, filed Oct. 
14, 1975, in the name of Richard Michael Lange disclose amino phenols and 
their use in lubricants. 
BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
This invention relates to additive combinations useful in oils of 
lubricating viscosity and normally liquid fuels. More particularly, it 
relates to additive combinations of amino phenols with certain 
detergent/dispersants and to oils and fuels containing same which are 
especially useful in two-cycle engines. 
(2) Prior Art 
The book "Lubricant Additives" by M. W. Ranney, published by Noyes Data 
Corporation of Parkridge, N.J. (1973), discloses a number of metal salts 
of various sulfonic and carboxylic acids and of phenols which are useful 
as detergent/dispersants in lubricating oil products. The book also 
entitled "Lubricant Additives" by C. V. Smallheer and R. K. Smith, 
published by the Lezius-Hiles Co. of Cleveland, Ohio (1967), similarly 
discloses a number of detergent/dispersants including sulfonates, phenates 
and carboxylates as well as alkyl and alkenyl succinimides and other high 
molecular weight amides and polyamides which are useful as dispersants. 
Other literature, particularly patents, which also disclose similar 
subject matter will be noted at appropriate points in the following 
specification. 
(3) General Background 
It is well known that additives are commonly added to engine lubricant and 
fuel compositions to prevent deposit formation on engine and fuel system 
surfaces with which the lubricant or fuel may come in contact. Such 
deposits interfere with proper circulation of lubricants in the engine. 
They can also act as abrasives to increase wear of engine parts; in 
extreme cases, such deposits may even hinder movement of engine parts. 
Deposits from fuels can interfere with proper carburetor operation, 
increase spark plug fouling, and the like. 
Among the engines which utilize such lubricants and fuels are two-cycle 
(two-stroke), spark-ignited internal combustion engines including rotary 
engines such as the Wankel-type engine. Use of these types of engines has 
steadily increased over the past several decades and they are presently 
found in power lawn mowers and other power operated garden equipment, 
power chain saws, pumps, electrical generators, marine out-board engines, 
snow-mobiles, motorcycles, other light-weight wheeled vehicles and the 
like. 
The increasing use of two-cycle engines, coupled with the increasing 
severity of the conditions under which they have been operated and the 
need to maximize usuage of petroleum-derived materials in the face of 
increasing shortages, has led to an increasing demand for oils and fuels 
which adequately lubricate such engines (it is a common practice to add 
the oils used to lubricate such engines to the fuel). 
Among the problems associated with the lubrication of two-cycle engines are 
piston ring sticking, rusting, lubrication failure of connecting rod and 
main bearings, and deposit formation as noted above. The formation of 
varnish is a particularly vexatious problem since the build-up of varnish 
on piston and cylinder walls can cause loss of compression through seal 
failing. This is particularly damaging in two-cycle engines since they 
depend on suction to draw the new fuel charge into the exhausted cylinder. 
The unique problems and techniques associated with the lubrication of 
two-cycle engines has led to a recognition in the art of two-cycle engine 
lubricants (and fuels containing same) as distinct types of lubricants and 
fuels. Similarly, additive concentrates for treating such fuels and 
lubricants have also been recognized to be a distinct field in the art. 
See, for example, U.S. Pat. Nos. 3,085,975; 3,004,837; and 3,753,905. 
The inventions described herein include novel additive combinations for 
lubricating oils and normally liquid fuels, in general, and particularly 
for oils and fuels used in two-cycle engines. 
(4) Objects 
Therefore, it is an object of this invention to provide novel additive 
combinations. 
It is a further object of this invention to provide novel lubricants, fuels 
and additive concentrates containing the novel additive combinations. 
It is a particular object of this invention to provide novel additive 
combinations and lubricants and fuels containing the same for use in 
two-cycle, spark-ignited engines as well as novel means for operating such 
engines. 
Other objects will be apparent to those skilled in the art upon review of 
the present specification. 
SUMMARY OF THE INVENTION 
This invention comprises a nitrogen-containing organic composition 
comprising a combination of: 
(A) at least one amino phenol of the general formula 
##STR1## 
wherein R is a substantially saturated, hydrocarbon-based substituent of 
at least 10 aliphatic carbon atoms; a, b and c are each independently an 
integer of one up to three times the number of aromatic nuclei present in 
Ar, with the proviso that the sum of a, b and c does not exceed the 
unsatisfied valences of Ar; and Ar is an aromatic moiety having 0-3 
optional substituents selected from the group consisting of lower alkyl, 
lower alkoxy, nitro, halo or combinations of two or more of said 
substituents; and 
(B) at least one detergent/dispersant selected from the group consisting of 
(I) at least one neutral or basic metal salt of an organic sulfur acid, 
phenol or carboxylic acid; 
(II) at least one hydrocarbyl-substituted amine wherein the hydrocarbyl 
substituent is substantially aliphatic and contains at least twelve carbon 
atoms, with the proviso that said amine is not the amino phenol (A); 
(iii) at least one acylated, nitrogen-containing compound having a 
substituent of at least 10 aliphatic carbon atoms made by reacting a 
carboxylic acid acylating agent with at least one amino compound 
containing at least one &gt;NH group, said acylating agent being linked to 
said amino compound through an imido, amido, amidine, or acyloxy ammonium 
linkage; and 
(IV) at least one nitrogen-containing condensate of a phenol, aldehyde and 
amino compound having at least one &gt;NH group. 
Lubricants based on oils of lubricating viscosity and normally liquid 
engine fuels as well as additive concentrates containing the 
above-described combinations are also part of this invention. 
DETAILED DESCRIPTION OF THE INVENTION 
(A) The Amino Phenols 
The aromatic moiety, Ar, of Formula I can be a single aromatic nucleus such 
as a benzene nucleus, a pyridine nucleus, a thiophene nucleus, a 
1,2,3,4-tetrahydronaphthalene nucleus, etc., or a polynuclear aromatic 
moiety. Such polynuclear moieties can be of the fused type; that is, 
wherein at least one aromatic nucleus is fused at two points to another 
nucleus such as found in naphthalene, anthracene, the azanaphthalenes, 
etc. Alternatively, such polynuclear aromatic moieties can be of the 
linked type wherein at least two nuclei (either mono- or polynuclear) are 
linked through bridging linkages to each other. Such bridging linkages can 
be chosen from the group consisting of carbon-to-carbon single bonds, 
ether linkages, keto linkages, sulfide linkages, polysulfide linkages of 2 
to 6 sulfur atoms, sulfinyl linkages, sulfonyl linkages, methylene 
linkages, alkylene linkages, di-(lower alkyl)methylene linkages, lower 
alkylene ether linkages, alkylene keto linkages, lower alkylene sulfur 
linkages, lower alkylene polysulfide linkages of 2 to 6 carbon atoms, 
amino linkages, polyamino linkages and mixtures of such divalent bridging 
linkages. In certain instances, more than one bridging linkage can be 
present in Ar between aromatic nuclei. For example, a fluorene nucleus has 
two benzene nuclei linked by both a methylene linkage and a covalent bond. 
Such a nucleus may be considered to have 3 nuclei but only two of them are 
aromatic. Normally, however, Ar will contain only carbon atoms in the 
aromatic nuclei per se (plus any lower alkyl or alkoxy substituent 
present). 
The number of aromatic nuclei, fused, linked or both, in Ar can play a role 
in determining the integer values of a, b and c in Formula I. For example, 
when Ar contains a single aromatic nucleus, a, b and c are each 
independently 1 to 4. When Ar contains two aromatic nuclei, a, b and c can 
each be an integer of 1 to 8, that is, up to three times the number of 
aromatic nuclei present (in naphthalene, 2). With a tri-nuclear Ar moiety, 
a, b and c can each be an integer of 1 to 12. For example, when Ar is a 
biphenyl or a naphthyl moiety, a, b and c can each independently be an 
integer of 1 to 8. The values of a, b and c are obviously limited by the 
fact that their sum cannot exceed the total unsatisfied valences of Ar. 
The single ring aromatic nucleus which can be the Ar moiety can be 
represented by the general formula 
EQU ar(Q).sub.m 
wherein ar represents a single ring aromatic nucleus (e.g., benzene) of 4 
to 10 carbons, each Q independently represents a lower alkyl group, lower 
alkoxy group, nitro group, or halogen atom, and m is 0 to 3. As used in 
this specification and appended claims, "lower" refers to groups having 7 
or less carbon atoms such as lower alkyl and lower alkoxyl groups. Halogen 
atoms include fluorine, chlorine, bromine and iodine atoms; usually, the 
halogen atoms are fluorine and chlorine atoms. 
Specific examples of single ring Ar moieties are the following: 
##STR2## 
wherein Me is methyl, Et is ethyl, Pr is n-propyl, and Nit is nitro. 
When Ar is a polynuclear fused-ring aromatic moiety, it can be represented 
by the general formula 
EQU ar ( ar ) .sub.m', (Q).sub.mm' 
wherein ar, Q and m are as defined hereinabove, m' is 1 to 4 and 
represent a pair of fusing bonds fusing two rings so as to make two carbon 
atoms part of the rings of each of two adjacent rings. Specific examples 
of fused ring aromatic moieties Ar are: 
##STR3## 
When the aromatic moiety Ar is a linked polynuclear aromatic moiety it can 
be represented by the general formula 
EQU ar--Lng-ar--.sub.w (Q).sub.mw 
wherein w is an integer of 1 to about 20, ar is as described above with the 
proviso that there are at least 3 unsatisfied (i.e., free) valences in the 
total of ar groups, Q and m are as defined hereinbefore, and each Lng is a 
bridging linkage individually chosen from the group consisting of 
carbon-to-carbon single bonds, ether linkages (e.g. --O--), keto linkages 
(e.g., 
##STR4## 
sulfide linkages (e.g., --S--), polysulfide linkages of 2 to 6 sulfur 
atoms (e.g., --S.sub.2 --.sub.6 --), sulfinyl linkages (e.g., --S(O)--), 
sulfonyl linkages (e.g., --S(O).sub.2 --), lower alkylene linkages (e.g., 
##STR5## 
etc.), di(lower alkyl)-methylene linkages (e.g., CR.degree..sub.2 --), 
lower alkylene ether linkages (e.g., 
##STR6## 
etc.), lower alkylene sulfide linkages (e.g., wherein one or more --O--'s 
in the lower alkylene ether linkages is replaced with an --S-- atom), 
lower alkylene polysulfide linkages (e.g., wherein one or more --O--'s is 
replaced with a --S.sub.2 --.sub.6 group), amino linkages (e.g., 
##STR7## 
where alk is lower alkylene, etc.), polyamino linkages (e.g., 
##STR8## 
where the unsatisfied free N valences are taken up with H atoms or 
R.degree. groups), and mixtures of such bridging linkages (each R.degree. 
being a lower alkyl group). It is also possible that one or more of the ar 
groups in the above-linked aromatic moiety can be replaced by fused nuclei 
such as ar ( ar ) .sub.m'. 
Specific examples of linked moieties are: 
##STR9## 
Usually all these Ar moieties are unsubstituted except for the R, --OH and 
--NH.sub.2 groups (and any bridging groups). 
For such reasons as cost, availability, performance, etc., the Ar moiety is 
normally a benzene nucleus, lower alkylene bridged benzene nucleus, or a 
naphthalene nucleus. Thus, a typical Ar moiety is a benzene or naphthalene 
nucleus having 3 to 5 unsatisfied valences, so that one or two of said 
valences may be satisfied by a hydroxyl group with the remaining 
unsatisfied valences being, insofar as possible, either ortho or para to a 
hydroxyl group. Preferably, Ar is a benzene nucleus having at least 3 
unsatisfied valences so that one can be satisfied by a hydroxyl group with 
the remaining 2 or 3 being either ortho or para to the hydroxyl group. 
The Substantially Saturated Hydrocarbon-based Group R 
The amino phenols of the present invention contain, directly bonded to the 
aromatic moiety Ar, a substantially saturated monovalent hydrocarbon-based 
group R of at least about 10 aliphatic carbon atoms. This R group can have 
up to about 400 aliphatic carbon atoms. More than one such group can be 
present, but usually, no more than 2 or 3 such groups are present for each 
aromatic nucleus in the aromatic moiety Ar. The total number of R groups 
present is indicated by the value for "a" in Formula I. Usually, the 
hydrocarbon-based group has at least about 30, more typically, at least 
about 50 aliphatic carbon atoms and up to about 750, more typically, up to 
about 300 aliphatic carbon atoms. 
Generally, the hydrocarbon-based groups R are made from homo- or 
interpolymers (e.g., copolymers, terpolymers) of mono- and di-olefins 
having 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, 
isobutene, butadiene, isoprene, 1-hexene, 1-octene, etc. Typically, these 
olefins are 1-monoolefins such as homopolymers of ethylene. The R groups 
can also be derived from the halogenated (e.g., chlorinated or brominated) 
analogs of such homo- or interpolymers. The R groups can, however, be made 
from other sources, such as monomeric high molecular weight alkenes (e.g., 
1-tetracontene) and chlorinated analogs and hydrochlorinated analogs 
thereof, aliphatic petroleum fractions, particularly paraffin waxes and 
cracked and chlorinated analogs and hydrochlorinated analogs thereof, 
white oils, synthetic alkenes such as those produced by the Ziegler-Natta 
process (e.g., poly(ethylene) greases) and other sources known to those 
skilled in the art. Any unsaturation in the R groups may be reduced or 
eliminated by hydrogenation according to procedures known in the art 
before the nitration step described hereafter. 
As used herein, the term "hydrocarbon-based" denotes a group having a 
carbon atom directly attached to the remainder of the molecule and having 
a predominately hydrocarbon character within the context of this 
invention. Therefore, hydrocarbon-based groups can contain up to one 
non-hydrocarbon radical for every ten carbon atoms provided this 
non-hydrocarbon radical does not significantly alter the predominately 
hydrocarbon character of the group. Those skilled in the art will be aware 
of such radicals, which include, for example, hydroxyl, halo (especially 
chloro and fluoro), alkoxyl, alkyl mercapto, alkyl sulfoxy, etc. Usually, 
however, the hydrocarbon-based groups R are purely hydrocarbyl and contain 
no such non-hydrocarbyl radicals. 
The hydrocarbon-based groups R are substantially saturated. By 
substantially saturated it is meant that the group contains no more than 
one carbon-to-carbon unsaturated bond for every ten carbon-to-carbon 
single bonds present. Usually, they contain no more than one 
carbon-to-carbon non-aromatic unsaturated bond for every 50 
carbon-to-carbon bonds present. 
The hydrocarbon-based groups of the amino phenols of this invention are 
also substantially aliphatic in nature, that is, they contain no more than 
one non-aliphatic moiety (cycloalkyl, cycloalkenyl or aromatic) group of 
six or less carbon atoms for every ten carbon atoms in the R group. 
Usually, however, the R groups contain no more than one such non-aliphatic 
group for every fifty carbon atoms, and in many cases, they contain no 
such non-aliphatic groups at all; that is, the typical R groups are purely 
aliphatic. Typically, these purely aliphatic R groups are alkyl or alkenyl 
groups. 
Specific examples of the substantially saturated hydrocarbon-based R groups 
are the following: 
a tetra(propylene) group 
a tri(isobutene) group 
a tetracontanyl group 
a henpentacontanyl group 
a mixture of poly(ethylene/propylene) groups of about 35 to about 70 carbon 
atoms 
a mixture of the oxidatively or mechanically degraded 
poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms 
a mixture of poly(propylene/1-hexane) groups of about 80 to about 150 
carbon atoms 
a mixture of poly(isobutene) groups having between 20 and 32 carbon atoms 
a mixture of poly(isobutene) groups having an average of 50 to 75 carbon 
atoms 
A preferred source of the group R are poly(isobutene)s obtained by 
polymerization of a C.sub.4 refinery stream having a butene content of 35 
to 75 weight percent and isobutene content of 15 to 60 weight percent in 
the presence of a Lewis acid catalyst such as aluminum trichloride or 
boron trifluoride. These polybutenes contain predominantely (greater than 
80% of total repeating units) isobutene repeating units of the 
configuration 
##STR10## 
The attachment of the hydrocarbon-based group R to the aromatic moiety Ar 
of the amino phenols of this invention can be accomplished by a number of 
techniques well known to those skilled in the art. One particularly 
suitable technique is the Friedel-Crafts reaction, wherein an olefin 
(e.g., a polymer containing an olefinic bond), or halogenated or 
hydrohalogenated analog thereof, is reacted with a phenol. The reaction 
occurs in the presence of a Lewis acid catalyst (e.g., boron trifluoride 
and its complexes with ethers, phenols, hydrogen fluoride, etc., aluminum 
chloride, aluminum bromide, zinc dichloride, etc.). Methods and conditions 
for carrying out such reactions are well known to those skilled in the 
art. See, for example, the discussion in the article entitled, "Alkylation 
of Phenols" in "Kirk-Othmer Encyclopedia of Chemical Technology", Second 
Edition, Vol. 1, pages 894-895, Interscience Publishers, a division of 
John Wiley and Company, N.Y., 1963. Other equally appropriate and 
convenient techniques for attaching the hydrocarbon-based group R to the 
aromatic moiety Ar will occur readily to those skilled in the art. 
As will be appreciated from inspection of Formula I the amino phenols of 
this invention contain at least one of each of the following substituents: 
a hydroxyl group, a R group as defined above, and a primary amine group, 
--NH.sub.2. Each of the foregoing groups must be attached to a carbon atom 
which is a part of an aromatic nucleus in the Ar moiety. They need not, 
however, each be attached to the same aromatic ring if more than one 
aromatic nucleus is present in the Ar moiety. 
In a preferred embodiment, the amino phenols of this invention contain one 
each of the foregoing substituents (i.e., a, b and c are each 1) and but a 
single aromatic ring, most preferably benzene. This preferred class of 
amino phenols can be represented by the formula 
##STR11## 
wherein the R' group is a substantially saturated hydrocarbon-based group 
of about 30 to about 400 aliphatic carbon atoms located ortho or para to 
the hydroxyl group, R" is a lower alkyl, lower alkoxyl, nitro group or 
halogen atom and z is 0 or 1. Usually z is 0 and R' is a substantially 
saturated, purely hydrocarbyl aliphatic group. Often it is an alkyl or 
alkenyl group para to the --OH substituent. Often there is but one amine 
group, --NH.sub.2 in these preferred amino phenols but there can be two. 
In a still more preferred embodiment of this invention, the amino phenol is 
of the formula 
##STR12## 
wherein R' is derived from homopolymerized or interpolymerized C.sub.2 
-.sub.10 1-olefins and has an average of from about 30 to about 400 
aliphatic carbon atoms and R" and z are as defined above. Usually R' is 
derived from ethylene, propylene, butylene and mixtures thereof. 
Typically, it is derived from polymerized isobutene. Often R' has at least 
about 50 aliphatic carbon atoms and z is 0. 
The amino phenols of the present invention can be prepared by a number of 
synthetic routes. These routes can vary in the type reactions used and the 
sequence in which they are employed. For example, an aromatic hydrocarbon, 
such as benzene, can be alkylated with alkylating agent such as a 
polymeric olefin to form an alkylated aromatic intermediate. This 
intermediate can then be nitrated, for example, to form polynitro 
intermediate. The polynitro intermediate can in turn be reduced to a 
diamine, which can then be diazotized and reacted with water to convert 
one of the amino groups into a hydroxyl group and provide the desired 
amino phenol. Alternatively, one of the nitro groups in the polynitro 
intermediate can be converted to a hydroxyl group through fusion with 
caustic to provide a hydroxy-nitro alkylated aromatic which can then be 
reduced to provide the desired amino phenol. 
Another useful route to the amino phenols of this invention involves the 
alkylation of a phenol with an olefinic alkylating agent to form an 
alkylated phenol. This alkylated phenol can then be nitrated to form an 
intermediate nitro phenol which can be converted to the desired amino 
phenols by reducing at least some of the nitro groups to amino groups. 
Techniques for alkylating phenols are well known to those skilled in the 
art as the above-noted article in Kirk-Othmer "Encyclopedia of Chemical 
Technology" demonstrates. Techniques for nitrating phenols are also known. 
See, for example, in Kirk-Othmer "Encyclopedia of Chemical Technology", 
Second Edition, Vol. 13, the article entitled "Nitrophenols", page 888 et 
seq., as well as the treatises "Aromatic Substitution; Nitration and 
Halogenation" by P. B. D. De La Mare and J. H. Ridd, N. Y., Academic 
Press, 1959; "Nitration and Aromatic Reactivity" by J. G. Hogget, London, 
Cambridge University Press, 1961; and "The Chemistry of the Nitro and 
Nitroso Groups", Henry Feuer, Editor, Interscience Publishers, N.Y., 1969. 
Aromatic hydroxy compounds can be nitrated with nitric acid, mixtures of 
nitric acid with acids such as sulfuric acid or boron trifluoride, 
nitrogen tetraoxide, nitronium tetrafluoroborates and acyl nitrates. 
Generally, nitric acid of a concentration of, for example, about 30-90% is 
a convenient nitrating reagent. Substantially inert liquid diluents and 
solvents such as acetic or butyric acid can aid in carrying out the 
reaction by improving reagent contact. 
Conditions and concentrations for nitrating hydroxy aromatic compounds are 
also well known in the art. For example, the reaction can be carried out 
at temperatures of about -15.degree. C. to about 150.degree. C. Usually 
nitration is conveniently carried out between about 25.degree.-75.degree. 
C. 
Generally, depending on the particular nitrating agent about 0.5-4 moles of 
nitrating agent is used for every mole of aromatic nucleus present in the 
hydroxy aromatic intermediate to be nitrated. If more than one aromatic 
nucleus is present in the Ar moiety, the amount of nitrating agent can be 
increased proportionately according to the number of such nuclei present. 
For example, a mole of naphthalene-based aromatic intermediate has, for 
purposes of this invention, the equivalent of two "single ring" aromatic 
nuclei so that about 1-4 moles of nitrating agent would generally be used. 
When nitric acid is used as a nitrating agent usually about 1.0 to about 
3.0 moles per mole of aromatic nucleus is used. Up to about a 5-molar 
excess of nitrating agent (per "single ring" aromatic nucleus) may be used 
when it is desired to drive the reaction forward or carry it out rapidly. 
Nitration of a hydroxy aromatic intermediate generally takes 0.25 to 24 
hours, though it may be convenient to react the nitration mixture for 
longer periods, such as 96 hours. 
Reduction of aromatic nitro compounds to the corresponding amines is also 
well known. See, for example, the article entitled "Amination by 
Reduction" in Kirk-Othmer "Encyclopedia of Chemical Technology", Second 
Edition, Vol. 2, pages 76-99. Generally, such reductions can be carried 
out with, for example, hydrogen, carbon monoxide or hydrazine, (or 
mixtures of same) in the presence of metallic catalysts such as palladium, 
platinum and its oxides, nickel, copper chromite, etc. Co-catalysts such 
as alkali or alkaline earth metal hydroxides or amines (including amino 
phenols) can be used in these catalyzed reductions. 
Reduction can also be accomplished through the use of reducing metals in 
the presence of acids, such as hydrochloric acid. Typical reducing metals 
are zinc, iron and tin; salts of these metals can also be used. 
Nitro groups can also be reduced in the Zinin reaction, which is discussed 
in "Organic Reactions", Vol. 20, John Wiley & Sons, N.Y. 1973, page 455 et 
seq. Generally, the Zinin reaction involves reduction of a nitro group 
with divalent negative sulfur compounds, such as alkali metal sulfides, 
polysulfides and hydrosulfides. 
The nitro groups can be reduced by electrolytic action; see, for example, 
the "Amination by Reduction" article, referred to above. Typically the 
amino phenols of this invention are obtained by reduction of nitro phenols 
with hydrogen in the presence of a metallic catalyst such as discussed 
above. This reduction is generally carried out at temperatures of about 
15.degree.-250.degree. C., typically, about 50.degree.-150.degree. C., and 
hydrogen pressures of about 0-2000 psig, typically, about 50-250 psig. The 
reaction time for reduction usually varies between about 0.5-50 hours. 
Substantially inert liquid diluents and solvents, such as ethanol, 
cyclohexane, etc., can be used to facilitate the reaction. The amino 
phenol product is obtained by well-known techniques such as distillation, 
filtration, extraction, and so forth. 
The reduction is carried out until at least about 50%, usually about 80%, 
of the nitro groups present in the nitro intermediate mixture are 
converted to amino groups. The typical route to the amino phenols of this 
invention just described can be summarized as 
(I) nitrating with at least one nitrating agent at least one compound of 
the formula 
##STR13## 
wherein R is a substantially saturated hydrocarbon-based group of at least 
10 aliphatic carbon atoms; a and c are each independently an integer of 1 
up to three times the number of aromatic nuclei present in Ar with the 
proviso that the sum of a, b and c does not exceed the unsatisfied 
valences of Ar'; and Ar' is an aromatic moiety having 0 to 3 optional 
substituents selected from the group consisting of lower alkyl, lower 
alkoxyl, nitro, and halo, or combinations of two or more optional 
substituents, with the provisos that (a) Ar' has at least one hydrogen 
atom directly bonded to a carbon atom which is part of an aromatic 
nucleus, and (b) when Ar' is a benzene having only one hydroxyl and one R 
substituent, the R substituent is ortho or para to said hydroxyl 
substituent, to form a first reaction mixture containing a nitro 
intermediate, and (II) reducing at least about 50% of the nitro groups in 
said first reaction mixture to amino groups. 
Usually this means reducing at least about 50% of the nitro groups to amino 
groups in a compound or mixture of compounds of the formula 
##STR14## 
wherein R is a substantially saturated hydrocarbon-based substituent of at 
least 10 aliphatic carbon atoms; a, b and c are each independently an 
integer of 1 up to three times the number of aromatic nuclei present in Ar 
with the proviso that the sum of a, b and c does not exceed the 
unsatisfied valences of Ar; and Ar is an aromatic moiety having 0 to 3 
optional substituents selected from the group consisting of lower alkyl, 
lower alkoxyl, halo, or combinations of two or more of said optional 
substituents; with the proviso that when Ar is a benzene nucleus having 
only one hydroxyl and one R substituent, the R substituent is ortho or 
para to said hydroxyl substituent. 
(B) The Detergent/Dispersants 
In general the detergent/dispersants (B) used in the combinations of this 
invention are materials known to those skilled in the art and they have 
been described in numerous books, articles and patents. A number of these 
are noted hereinbelow in relation to specific types of 
detergent/dispersants and where this is done it is to be understood that 
they are incorporated by reference for their disclosures relevant to the 
subject matter discussed at the point in the specification in which they 
are identified. 
(B) (I) The Neutral or Basic Metal Salts of Organic Sulfur Acids, 
Carboxylic Acids or Phenols 
The choice of metal used to make these salts is usually not critical and 
therefore virtually any metal can be used. For reasons of availability, 
cost and maximum effectiveness, certain metals are more commonly used. 
These include the alkali and alkaline earth metals (i.e., the Group IA and 
IIA metals excluding francium and radium). Group IIB metals as well as 
polyvalent metals such as aluminum, chromium, molybdenum, wolfram, 
manganese, iron, cobalt, nickel, and copper can also be used. Salts 
containing a mixture of ions of two or more of these metals are often 
used. 
These salts can be neutral or basic. The former contain an amount of metal 
cation just sufficient to neutralize the acidic groups present in salt 
anion; the former contain an excess of metal cation and are often termed 
overbased, hyperbased or superbased salts. 
These basic and neutral salts can be of oil-soluble organic sulfur acids 
such as sulfonic, sulfamic, thiosulfonic, sulfinic, sulfenic, partial 
ester sulfuric, sulfurous and thiosulfuric acid. Generally they are salts 
of carbocyclic or aliphatic sulfonic acids. 
The carbocyclic sulfonic acids include the mono- or poly-nuclear aromatic 
or cycloaliphatic compounds. The oil-soluble sulfonates can be represented 
for the most part by the following formulae: 
EQU [R.sub.x --T--(SO.sub.3).sub.y ].sub.z M.sub.b Formula VI 
EQU [r'--(so.sub.3).sub.a ].sub.d M.sub.b Formula VII 
in the above formulae, M is either a metal cation as described hereinabove 
or hydrogen; T is a cyclic nucleus such as, for example, benzene, 
naphthalene, anthracene, phenanthrene, diphenylene oxide, thianthrene, 
phenothioxine, diphenylene sulfide, phenothiazine, diphenyl oxide, 
diphenyl sulfide, diphenylamine, cyclohexane, petroleum naphthenes, 
decahydro-naphthalene, cyclopentane, etc.; R in Formula VI is an aliphatic 
group such as alkyl, alkenyl, alkoxy, alkoxyalkyl, carboalkoxyalkyl, etc.; 
x is at least 1, and R.sub.x + T contains a total of at least about 15 
carbon atoms. R' in Formula VII is an aliphatic radical containing at 
least about 15 carbon atoms and M is either a metal cation or hydrogen. 
Examples of types of the R' radical are alkyl, alkenyl, alkoxyalkyl, 
carboalkoxyalkyl, etc. Specific examples of R' are groups derived from 
petrolatum, saturated and unsaturated paraffin wax, and polyolefins, 
including polymerized C.sub.2, C.sub.3, C.sub.4, C.sub.5, C.sub.6, etc., 
olefins containing from about 15 to 7000 or more carbon atoms. The groups 
T, R, and R' in the above formulae can also contain other inorganic or 
organic substituents in addition to those enumerated above such as, for 
example, hydroxy, mercapto, halogen, nitro, amino, nitroso, sulfide, 
disulfide, etc. In Formula VI, x, y, z and b are at least 1, and likewise 
in Formula VII, a, b and d are at least 1. 
The following are specific examples of oil-soluble sulfonic acids coming 
within the scope of Formulae I and II above, and it is to be understood 
that such examples serve also to illustrate the salts of such sulfonic 
acids useful in this invention. In other words, for every sulfonic acid 
enumerated it is intended that the corresponding neutral and basic metal 
salts thereof are also understood to be illustrated. Such sulfonic acids 
are mahogany sulfonic acids; bright stock sulfonic acids; sulfonic acids 
derived from lubricating oil fractions having a Saybolt viscosity from 
about 100 seconds at 100.degree. F. to about 200 seconds at 210.degree. 
F.; petrolatum sulfonic acids; mono- and poly-wax substituted sulfonic and 
polysulfonic acids of, e.g., benzene, naphthalene, phenol, diphenyl ether, 
naphthalene disulfide, diphenylamine, thiophene, alpha-chloronaphthalene, 
etc.; other substituted sulfonic acids such as alkyl benzene sulfonic 
acids (where the alkyl group has at least 8 carbons), cetylphenol 
mono-sulfide sulfonic acids, dicetyl thianthrene disulfonic acids, 
dilauryl beta naphthyl sulfonic acids, dicapryl nitronaphthalene sulfonic 
acids, and alkaryl sulfonic acids such as dodecyl benzene "bottoms" 
sulfonic acids. 
The latter are acids derived from benzene which has been alkylated with 
propylene tetramers or isobutene trimers to introduce 1, 2, 3, or more 
branched-chain C.sub.12 substituents on the benzene ring. Dodecyl benzene 
bottoms, principally mixtures of mono- and di-dodecyl benzenes, are 
available as by-products from the manufacture of household detergents. 
Similar products obtained from alkylation bottoms formed during 
manufacture of linear alkyl sulfonates (LAS) are also useful in making the 
sulfonates used in this invention. 
The production of sulfonates from detergent manufacture by-products by 
reaction with, e.g., SO.sub.3, is well known to those skilled in the art. 
See, for example, the article "Sulfonates" in Kirk-Othmer "Encyclopedia of 
Chemical Technology", Second Edition, Vol. 19, pp. 291 et seq. published 
by John Wiley & Sons, N.Y. (1969). 
Other descriptions of neutral and basic sulfonate salts and techniques for 
making them can be found in the following U.S. Pat. Nos.: 2,174,110; 
2,174,506; 2,174,508; 2,193,824; 2,197,800; 2,202,781; 2,212,786; 
2,213,360; 2,228,598; 2,233,676; 2,239,974; 2,263;312; 2,276,090; 
2,276,097; 2,315,514; 2,319,121; 2,321,022; 2,333,568; 2,333,788; 
2,335,259; 2,337,552; 2,346,568; 2,366,027; 2,374,193; 2,383,319; 
3,312,618; 3,471,403; 3,488,284; 3,595,790; and 3,798,012. These are 
hereby incorporated by reference for their disclosures in this regard. 
Also included are aliphatic sulfonic acids such as paraffin wax sulfonic 
acids, unsaturated paraffin wax sulfonic acids, hydroxy-substituted 
paraffin wax sulfonic acids, hexapropylene sulfonic acids, tetra-amylene 
sulfonic acids, polyisobutene sulfonic acids wherein the polyisobutene 
contains from 20 to 7000 or more carbon atoms, chloro-substituted paraffin 
wax sulfonic acids, nitroparaffin wax sulfonic acids, etc.; cycloaliphatic 
sulfonic acids such as petroleum naphthene sulfonic acids, cetyl 
cyclopentyl sulfonic acids, lauryl cyclohexyl sulfonic acids, 
bis-(di-isobutyl) cyclohexyl sulfonic acids, mono- or poly-wax substituted 
cyclohexyl sulfonic acids, etc. 
With respect to the sulfonic acids or salts thereof described herein and in 
the appended claims, it is intended herein to employ the term "petroleum 
sulfonic acids" or "petroleum sulfonates" to cover all sulfonic acids or 
the salts thereof derived from petroleum products. A particularly valuable 
group of petroleum sulfonic acids are the mahogany sulfonic acids (so 
called because of their reddish-brown color) obtained as a by-product from 
the manufacture of petroleum white oils by a sulfuric acid process. 
Generally Group IA, IIA and IIB neutral and basic salts of the 
above-described synthetic and petroleum sulfonic acids are useful in the 
practice of this invention. 
The carboxylic acids from which suitable neutral and basic salts for use in 
this invention can be made include aliphatic, cycloaliphatic, and aromatic 
mono- and polybasic carboxylic acids such as the naphthenic acids, alkyl- 
or alkenyl-substituted cyclopentanoic acids, alkyl- or alkenyl-substituted 
cyclohexanoic acids, alkyl- or alkenyl-substituted aromatic carboxylic 
acids. The aliphatic acids generally contain at least eight carbon atoms 
and preferably at least twelve carbon atoms. Usually they have no more 
than about 400 carbon atoms. Generally, if the aliphatic carbon chain is 
branched, the acids are more oil-soluble for any given carbon atoms 
content. The cycloaliphatic and aliphatic carboxylic acids can be 
saturated or unsaturated. Specific examples include 2-ethylhexanoic acid, 
.alpha.-linolenic acid, propylene-tetramer-substituted maleic acid, 
behenic acid, isostearic acid, pelargonic acid, capric acid, palmitoleic 
acid, linoleic acid, lauric acid, oleic acid, ricinoleic acid, undecylic 
acid, dioctylcyclopentane carboxylic acid, myristic acid, 
dilauryldecahydronaphthalene carboxylic acid, stearyl-octahydroindene 
carboxylic acid, palmitic acid, commercially available mixtures of two or 
more carboxylic acids such as tall oil acids, rosein acids, and the like. 
A preferred group of oil-soluble carboxylic acids useful in preparing the 
salts used in the present invention are the oil-soluble aromatic 
carboxylic acids. These acids are represented by the general formula: 
##STR15## 
where R* is an aliphatic hydrocarbon-based group of at least four carbon 
atoms, and no more than about 400 aliphatic carbon atoms, a is an integer 
of from one to four, Ar* is a polyvalent aromatic hydrocarbon nucleus of 
up to about 14 carbon atoms each X is independently a sulfur or oxygen 
atom, and m is an integer of from one to four with the proviso that R* and 
a are such that there is an average of at least 8 aliphatic carbon atoms 
provided by the R* groups for each acid molecule represented by Formula 
VIII. Examples of aromatic nuclei represented by the variable Ar* are the 
polyvalent aromatic radicals derived from benzene, naphthalene, 
anthracene, phenanthrene, indene, fluorene, biphenyl, and the like. 
Generally, the radical represented by Ar* will be a polyvalent nucleus 
derived from benzene or naphthalene such as phenylenes and naphthylene, 
e.g., methylphenylenes, ethoxyphenylenes, nitrophenylenes, 
isopropylphenylenes, hydroxyphenylenes, mercaptophenylenes, 
N,N-diethylaminophenylenes, chlorophenylenes, dipropoxynaphthylenes, 
triethylnaphthylenes, and similar tri-, tetra-, pentavalent nuclei 
thereof, etc. 
The R* groups are usually purely hydrocarbyl groups, preferably groups such 
as alkyl or alkenyl radicals. However, the R* groups can contain small 
number substituents such as phenyl, cycloalkyl (e.g., cyclohexyl, 
cyclopentyl, etc.) and nonhydrocarbon groups such as nitro, amino, halo 
(e.g., chloro, bromo, etc.), lower alkoxy, lower alkyl mercapto, oxo 
substituents (i.e.,.dbd.O), thio groups (i.e., .dbd.S), interrupting 
groups such as --NH--, --O--, --S--, and the like provided the essentially 
hydrocarbon character of the R* group is retained. The hydrocarbon 
character is retained for purposes of this invention so long as any 
non-carbon atoms present in the R* groups do not account for more than 
about 10% of the total weight of the R* groups. 
Examples of R* groups include butyl, isobutyl, pentyl, octyl, nonyl, 
dodecyl, docosyl, tetracontyl, 5-chlorohexyl, 4-ethoxypentyl, 4-hexenyl, 
3-cyclohexyloctyl, 4-(p-chlorophenyl)-octyl, 2,3,5-trimethylheptyl, 
4-ethyl-5-methyloctyl, and substituents derived from polymerized olefins 
such as polychloroprenes, polyethylenes, polypropylenes, polyisobutylenes, 
ethylene-propylene copolymers, chlorinated olefin polymers, oxidized 
ethylene-propylene copolymers, and the like. Likewise, the group Ar* may 
contain non-hydrocarbon substituents, for example, such diverse 
substituents as lower alkoxy, lower alkyl mercapto, nitro, halo, alkyl or 
alkenyl groups of less than four carbon atoms, hydroxy, mercapto, and the 
like. 
A group of particularly useful carboxylic acids are those of the formula: 
##STR16## 
where R*, X, Ar*, m and a are as defined in Formula VIII and p is an 
integer of 1 to 4, usually 1 to 2. Within this group, an especially 
preferred class of oil-soluble carboxylic acids are those of the formula: 
##STR17## 
where R** in Formula X is aliphatic hydrocarbon group containing at least 
4 to about 400 carbon atoms, a is an integer of from 1 to 3, b is 1 or 2, 
c is zero, 1, or 2 and preferably 1 with the proviso that R** and a are 
such that the acid molecules contain at least an average of about twelve 
aliphatic carbon atoms in the aliphatic hydrocarbon substituents per acid 
molecule. And within this latter group of oil-soluble carboxylic acids, 
the aliphatic-hydrocarbon substituted salicyclic acids wherein each 
aliphatic hydrocarbon substituent contains an average of at least about 
sixteen carbon atoms per substituent and one to three substituents per 
molecule are particularly useful. Salts prepared from such salicylic acids 
wherein the aliphatic hydrocarbon substituents are derived from 
polymerized olefins, particularly polymerized lower 1-mono-olefins such as 
polyethylene, polypropylene, polisobutylene, ethylene/propylene copolymers 
and the like and having average carbon contents of about 30 to about 400 
carbon atoms. 
The carboxylic acids corresponding to Formulae VIII-IX above are well known 
or can be prepared according to procedures known in the art. Carboxylic 
acids of the type illustrated by the above formulae and processes for 
preparing their neutral and basic metal salts are well known and 
disclosed, for example, in such U.S. Pat. Nos. as 2,197,832; 2,197,835; 
2,252,662; 2,252,664; 2,714,092, 3,410,798 and 3,595,791. 
Another type of neutral and basic carboxylate salt used in this invention 
are those derived from alkenyl succinates of the general formula 
##STR18## 
wherein R* is as defined above in Formula VIII. Such salts and means for 
making them are set forth in U.S. Pat. Nos. 3,271,130, 3,567,637 and 
3,632,510, which are hereby incorporated by reference in this regard. 
Other patents specifically describing techniques for making basic salts of 
the hereinabove-described sulfonic acids, carboxylic acids, and mixtures 
of any two or more of these include U.S. Pat. Nos. 2,501,731; 2,616,904; 
2,616,905; 2,616,906; 2,616,911; 2,616,924; 2,616,925; 2,617,049; 
2,777,874; 3,027,325; 3,256,186; 3,282,835; 3,384,585; 3,373,108; 
3,365,396; 3,342,733; 3,320,162; 3,312,618; 3,318,809; 3,471,403; 
3,488,284; 3,595,790; and 3,629,109. The disclosures of these patents are 
hereby incorporated in this present specification for their disclosures in 
this regard as well as for their disclosure of specific suitable basic 
metal salts. 
Neutral and basic salts of phenols (generally known as phenates) are also 
useful in the compositions of this invention and well known to those 
skilled in the art. The phenols from which these phenates are formed are 
of the general formula 
EQU (R*).sub.n (Ar*)(XH).sub.m Formula XII 
wherein R*, n, Ar*, X and m have the same meaning and preferences as 
described hereinabove with reference to Formula VIII. The same examples 
described with respect to Formula VIII also apply. 
A commonly available class of phenates are those made from phenols of the 
general formula 
##STR19## 
wherein a is an integer of 1-3, b is of 1 or 2, z is 0 or 1, R' in Formula 
XIII is a substantially saturated hydrocarbon-based substituent having an 
average of from 30 to about 400 aliphatic carbon atoms and R.sup.4 is 
selected from the group consisting of lower alkyl, lower alkoxyl, nitro, 
and halo groups. 
One particular class of phenates for use in this invention are the basic 
(i.e., overbased, etc.) Group IIA metal sulfurized phenates made by 
sulfurizing a phenol as described hereinabove with a sulfurizing agent 
such as sulfur, a sulfur halide, or sulfide or hydrosulfide salt. 
Techniques for making these sulfurized phenates are described in U.S. Pat. 
Nos. 2,680,096; 3,036,971 and 3,775,321 which are hereby incorporated by 
reference for their disclosures in this regard. 
Other phenates that are useful are those that are made from phenols that 
have been linked through alkylene (e.g., methylene) bridges. These are 
made by reacting single or multi-ring phenols with aldehydes or ketones, 
typically, in the presence of an acid or basic catalyst. Such linked 
phenates as well as sulfurized phenates are described in detail in U.S. 
Pat. Nos. 3,350,038; particularly columns 6-8 thereof, which is hereby 
incorporated by reference for its disclosures in this regard. 
Naturally, mixtures of two or more neutral and basic salts of the 
hereinabove described organic sulfur acid, carboxylic acids and phenols 
can be used in the compositions of this invention. Usually the neutral and 
basic salts will be sodium, lithium, magnesium, calcium, or barium salts 
including mixtures of two or more of any of these. 
(B) (II) The Hydrocarbyl-Substituted Amine 
The hydrocarbyl-substituted amines used in making the compositions of this 
invention are well known to those of skill in the art and they are 
described in a number of patents. Among these are U.S. Pat. Nos. 
3,275,554; 3,438,757; 3,454,555; 3,565,804; 3,755,433; and 3,822,209. 
These patents are hereby incorporated by their reference for their 
disclosure of suitable hydrocarbyl amines for use in the present invention 
including their method of preparation. 
A typical hydrocarbyl amine has the general formula: 
##STR20## 
wherein A is hydrogen, a hydrocarbyl group of from 1 to 10 carbon atoms, 
or hydroxyhydrocarbyl group of from 1 to 10 carbon atoms; X is hydrogen, a 
hydrocarbyl group of from 1 to 10 carbon atoms, or hydroxyhydrocarbyl 
group of from 1 to 10 carbon atoms, and may be taken together with A to 
form a ring of from 5 to 6 annular members and up to 12 carbon atoms; U is 
an alkylene group of from 2 to 10 carbon atoms, R.sup.2 is an aliphatic 
hydrocarbon group of from about 30 to 400 carbon atoms; a is an integer of 
from 0 to 10; b is an integer of from 0 to 1; a+2b is an integer of from 1 
to 10; c is an integer of from 1 to 5 and is as an average in the range of 
1 to 4, and equal to or less than the number of nitrogen atoms in the 
molecule; x is an integer of from 0 to 1; y is an integer of from 0 to 1; 
and x+y is equal to 1. 
In interpreting this formula, it is to be understood that the R.sup.2 and H 
atoms are attached to the unsatisfied nitrogen valences within the 
brackets of the formula. Thus, for example, the formula includes 
subgeneric formulae wherein the R.sup.2 is attached to terminal nitrogens 
and isomeric subgeneric formula wherein it is attached to non-terminal 
nitrogen atoms. Nitrogen atoms not attached to an R.sup.2 may bear a 
hydrogen or an AXN substituent. 
The hydrocarbyl amines useful in this invention and embraced by the above 
formula include monoamines of the general formula 
EQU AXNR.sup.2 . Formula XV 
illustrative of such monoamines are the following: 
poly(propylene)amine 
N,n-dimethyl-N-poly(ethylene/propylene)amine (50:50 mole ratio of monomers) 
poly(isobutene)amine 
N,n-di(hydroxyethyl)-N-poly(isobutene)amine 
poly(isobutene/1-butene/2-butene)amine (50:25:25 mole ratio of monomer) 
N-(2-hydroxypropyl)-N-poly(isobutene)amine 
N-poly(1-butene)-aniline 
N-poly(isobutene)-morpholine 
Among the hydrocarbyl amines embraced by the general Formula XIV as set 
forth above, are polyamines of the general formula 
##STR21## 
Illustrative of such polyamines are the following: N-poly(isobutene) 
ethylene diamine 
N-poly(propylene) trimethylene diamine 
N-poly(1-butene) diethylene triamine 
N',n'-poly(isobutene) tetraethylene pentamine 
N,n-dimethyl-N'-poly(propylene),1,3-propylene diamine 
The hydrocarbyl substituted amines useful in forming the compositions in 
this invention include certain N-aminohydrocarbyl morpholines which are 
not embraced in the general Formula XIV above. These 
hydrocarbyl-substituted aminohydrocarbyl morpholines have the general 
formula: 
##STR22## 
wherein R.sup.2 is an aliphatic hydrocarbon group of from about 30 to 
about 400 carbons, A is hydrogen, hydrocarbyl of from 1 to 10 carbon atoms 
or hydroxy hydrocarbyl group of from 1 to 10 carbon atoms and U is an 
alkylene group of from 2 to 10 carbon atoms. These hydrocarbyl-substituted 
aminohydrocarbyl morpholines as well as the polyamines described by 
Formula XV are among the typical hydrocarbyl-substituted amines used in 
preparing compositions of this invention. 
(B) (III) The Acylated Nitrogen-containing Compounds 
A number of acylated, nitrogen-containing compounds having a substituent of 
at least 10 aliphatic carbon atoms and made by reacting a carboxylic acid 
acylating agent with an amino compound are known to those skilled in the 
art. In such compositions the acylating agent is linked to the amino 
compound through an imido, amido, amidine or acyloxy ammonium linkage. The 
substituent of 10 aliphatic carbon atoms may be in either the carboxylic 
acid acylating agent derived portion of the molecule or in the amino 
compound derived portion of the molecule. Preferably, however, it is in 
the acylating agent portion. The acylating agent can vary from formic acid 
and its acylating derivatives to acylating agents having high molecular 
weight aliphatic substituents of up to 5,000, 10,000 or 20,000 carbon 
atoms. The amino compounds can vary from ammonia itself to amines having 
aliphatic substituents of up to about 30 carbon atoms. 
A typical class of acylated amino compounds useful in making the 
compositions of this invention are those made by reacting an acylating 
agent having an aliphatic substituent of at least 10 carbon atoms and a 
nitrogen compound characterized by the presence of at least one 
##STR23## 
group. Typically, the acylating agent will be a mono- or polycarboxylic 
acid (or reactive equivalent thereof) such as a substituted succinic or 
propionic acid and the amino compound will be a polyamine or mixture of 
polyamines, most typically, a mixture of ethylene polyamines. The 
aliphatic substituent in such acylating agents is often of at least about 
50 and up to about 400 carbon atoms. Usually it belongs to the same 
generic class as the R' group of the amino phenols (A) and therefore the 
preferences, examples and limitations discussed hereinabove relating to R' 
apply equally to this aliphatic substituent. Exemplary of amino compounds 
useful in making these acylated compounds are the following: (1) 
polyalkylene polyamines of the general formula 
##STR24## 
wherein each R'" is independently a hydrogen atom or a C.sub.1-12 
hydrocarbon-based group, with proviso that at least one R is a hydrogen 
atom, n is a whole number of 1 to 10 and U is a C.sub.2-10 alkylene group, 
(2) heterocyclic-substituted polyamines of the formula 
##STR25## 
wherein R'" and U are as defined hereinabove, m is 0 or a whole number of 
1 to 10, m' is a whole number of 1 to 10 and Y is an oxygen or divalent 
sulfur atom or a &gt;N-R'" group and (3) aromatic polyamines of the general 
formula 
EQU Ar(NR'".sub.2).sub.y Formula XX 
wherein Ar is an aromatic nucleus of 6 to about 20 carbon atoms, each R'" 
is as defined hereinabove and y is 2 to about 8. Specific examples of the 
polyalkylene polyamines (1) are ethylene diamine, 
tetra(ethylene)pentamine, tri(trimethylene)tetramine, 1,2-propylene 
diamine, etc. Specific examples of the heterocyclic-substituted polyamines 
(2) are N-2-aminoethyl piperazine, N-2 and N-3 amino propyl morpholine, 
N-3-(dimethyl amino) propyl piperazine, etc. Specific examples of the 
aromatic polyamines (3) are the various isomeric phenylene diamines, the 
various isomeric naphthylene diamines, etc. 
Many patents have described useful acylated nitrogen compounds including 
U.S. Pat. Nos. 3,172,892; 3,219,666; 3,272,746; 3,310,492; 3,341,542; 
3,444,170; 3,455,831; 3,455,832; 3,576,743; 3,630,904; 3,632,511; and 
3,804,763. A typical acylated nitrogen-containing compound of this class 
is that made by reacting a poly(isobutene)-substituted succinic anhydride 
acylating agent (e.g., anhydride, acid, ester, etc.) wherein the 
poly(isobutene) substituent has between about 50 to about 400 carbon atoms 
with a mixture of ethylene polyamines having 3 to about 7 amino nitrogen 
atoms per ethylene polyamine and about 1 to about 6 ethylene units made 
from condensation of ammonia with ethylene chloride. In view of the 
extensive disclosure of this type of acylated amino compound, further 
discussion of their nature and method of preparation is not needed here. 
Instead, the above-noted U.S. Patents are hereby incorporated by reference 
for their disclosure of acylated amino compounds and their method of 
preparation. 
Another type of acylated nitrogen compound belonging to this class is that 
made by reacting the afore-described alkylene amines with the 
afore-described substituted succinic acids or anhydrides and aliphatic 
mono-carboxylic acids having from 2 to about 22 carbon atoms. In these 
types of acylated nitrogen compounds, the mole ratio of succinic acid to 
mono-carboxylic acid ranges from about 1:0.1 to about 1:1. Typical of the 
mono-carboxylic acid are formic acid, acetic acid, dodecanoic acid, 
butanoic acid, oleic acid, stearic acid, the commercial mixture of stearic 
acid isomers known as isostearic acid, tolyl acid, etc. Such materials are 
more fully described in U.S. Pat. Nos. 3,216,936 and 3,250,715 which are 
hereby incorporated by reference for their disclosures in this regard. 
Still another type of acylated nitrogen compound useful in making the 
compositions of this invention is the product of the reaction of a fatty 
monocarboxylic acid of about 12-30 carbon atoms and the afore-described 
alkylene amines, typically, ethylene, propylene or trimethylene polyamines 
containing 2 to 8 amino groups and mixtures thereof. The fatty 
monocarboxylic acids are generally mixtures of straight and branched chain 
fatty carboxylic acids containing 12-30 carbon atoms. A widely used type 
of acylated nitrogen compound is made by reacting the afore-described 
alkylene polyamines with a mixture of fatty acids having from 5 to about 
30 mole percent straight chain acid and about 70 to about 95 percent mole 
branched chain fatty acids. Among the commercially available mixtures are 
those known widely in the trade as isostearic acid. These mixtures are 
produced as a by-product from the dimerization of unsaturated fatty acids 
as described in U.S. Pat. Nos. 2,812,342 and 3,260,671. 
The branched chain fatty acids can also include those in which the branch 
is not alkyl in nature, such as found in phenyl and cyclohexyl stearic 
acid and the chloro-stearic acids. Branched chain fatty carboxylic 
acid/alkylene polyamine products have been described extensively in the 
art. See for example, U.S. Pat. Nos. 3,110,673; 3,251,853; 3,326,801; 
3,337,459; 3,405,064; 3,429,674; 3,468,639; 3,857,791. These patents are 
hereby incorporated by reference for their disclosure of fatty 
acid/polyamine condensates and their use in lubricating oil formulations. 
(B) (IV) The Nitrogen-containing Condensates of Phenols, Aldehydes, and 
Amino Compounds 
The phenol/aldehyde/amino compound condensates useful in making the 
compositions of this invention include those generically referred to as 
Mannich condensates. Generally they are made by reacting simultaneously or 
sequentially at least one active hydrogen compound such as a 
hydrocarbon-substituted phenol (e.g., an alkyl phenol wherein the alkyl 
group has at least about 30 up to about 400 carbon atoms), having at least 
one hydrogen atom bonded to an aromatic carbon, with at least one aldehyde 
or aldehyde-producing material (typically formaldehyde or formaldehyde 
precursor) and at least one amino or polyamino compound having at least 
one NH group. The amino compounds include primary or secondary mono-amines 
having hydrocarbon substituents of 1 to 30 carbon atoms or 
hydroxyl-substituted hydrocarbon substituents of 1 to about 30 carbon 
atoms. Another type of typical amino compound are the polyamines described 
during the discussion of the acylated nitrogen-containing compounds. 
Exemplary mono-amines include methyl ethyl amine, methyl octadecyl amine, 
aniline, diethyl amine, diethanol amine, dipropyl amine and so forth. The 
following U.S. Patents contain extensive descriptions of Mannich 
condensates which can be used in making the compositions of this 
invention: 
U.S. PATENT NOS. 
2,459,112 
2,962,442 
2,984,550 
3,036,003 
3,166,516 
3,236,770 
3,355,270 
3,368,972 
3,413,347 
3,442,808 
3,448,047 
3,454,497 
3,459,661 
3,461,172 
3,493,520 
3,539,633 
3,558,743 
3,586,629 
3,591,598 
3,600,372 
3,634,515 
3,649,229 
3,697,574 
these patents are hereby incorporated by reference for their disclosures 
relating to the production and use of Mannich condensate products in 
lubricant compositions. 
Condensates made from sulfur-containing reactants can also be used in the 
compositions of the present invention. Such sulfur-containing condensates 
are described in U.S. Pat. Nos. 3,368,972; 3,649,229; 3,600,372; 
3,649,659; and 3,741,896. These patents are also incorporated by reference 
for their disclosure of sulfur-containing Mannich condensates. Generally 
the condensates used in making the compositions of this invention are made 
from a phenol bearing an alkyl substituent of about 6 to about 400 carbon 
atoms, more typically, 30 to about 250 carbon atoms. These typical 
condensates are made from formaldehyde or C.sub.2-7 aliphatic aldehyde and 
an amino compound such as those used in making the acylated 
nitrogen-containing compounds described under (B) (III). 
These preferred condensates are prepared by reacting about one molar 
portion of phenolic compound with about 1 to about 2 molar portions of 
aldehyde and about 1 to about 5 equivalent portions of amino compound (an 
equivalent of amino compound is its molecular weight divided by the number 
of .dbd.NH groups present). The conditions under which such condensation 
reactions are carried out are well known to those skilled in the art as 
evidenced by the above-noted patents. Therefore, these patents are also 
incorporated by reference for their disclosures relating to reaction 
conditions. 
A particularly preferred class of condensation products for use in the 
present invention are those made by a "2-step process" as disclosed in 
commonly assigned U.S. Ser. No. 451,644, filed Mar. 15, 1974. Briefly, 
these nitrogen-containing condensates are made by (1) reacting at least 
one hydroxy aromatic compound containing an aliphatic-based or 
cycloaliphatic-based substituent which has at least about 30 carbon atoms 
and up to about 400 carbon atoms with a lower aliphatic C.sub.1-7 aldehyde 
or reversible polymer thereof in the presence of an alkaline reagent, such 
as an alkali metal hydroxide, at a temperature up to about 150.degree. C.; 
(2) substantially neutralizing the intermediate reaction mixture thus 
formed; and (3) reacting the neutralized intermediate with at least one 
compound which contains an amino group having at least one 
##STR26## 
group. 
More preferably, these 2-step condensates are made from (a) phenols bearing 
a hydrocarbon-based substituent having about 30 to about 250 carbon atoms, 
said substituent being derived from a polymer of propylene, 1-butene, 
2-butene, or isobutene and (b) formaldehyde, or reversible polymer 
thereof, (e.g., trioxane, paraformaldehyde) or functional equivalent 
thereof, (e.g., methylal) and (c) an alkylene polyamine such as ethylene 
polyamines having between 2 and 10 nitrogen atoms. Further details as to 
this preferred class of condensates can be found in the hereinabove noted 
U.S. Serial No. 451,644, which is hereby incorporated by reference, for 
its disclosures relating to 2-step condensates. 
The following specific illustrative examples describe how to make the amino 
phenols and detergent/dispersants which comprise the compositions of this 
invention. In these examples, as well as in this specification and the 
appended claims, all percentages, parts and ratios are by weight, unless 
otherwise expressly stated to the contrary. Temperatures are in degrees 
centigrade (.degree. C.) unless expressly stated to the contrary.

EXAMPLE 1A 
A mixture of 4578 parts of a polyisobutene-substituted phenol prepared by 
boron trifluoride-phenol catalyzed alkylation of phenol with a 
polyisobutene having a number average molecular weight of approximately 
1000 (vapor phase osmometry), 3052 parts of diluent mineral oil and 725 
parts of textile spirits is heated to 60.degree. to achieve homogenity. 
After cooling to 30.degree., 319.5 parts of 16 molar nitric acid in 600 
parts of water is added to the mixture. Cooling is necessary to keep the 
mixture's temperature below 40.degree.. After the reaction mixture is 
stirred for an additional two hours, an aliquot of 3,710 parts is 
transferred to a second reaction vessel. This second portion is treated 
with an additional 127.8 parts of 16 molar nitric acid in 130 parts of 
water at 25.degree.-30.degree.. The reaction mixture is stirred for 1.5 
hours and then stripped to 220.degree./30 tor. Filtration provides an oil 
solution of the desired intermediate (IA). 
EXAMPLE 1B 
A mixture of 810 parts of the oil solution of the (IA) intermediate 
described in Example 1A, 405 parts of isopropyl alcohol and 405 parts of 
toluene is charged to an appropriately sized autoclave. Platinum oxide 
catalyst (0.81 part) is added and the autoclave is evacuated and purged 
with nitrogen four times to remove any residual air. Hydrogen is fed to 
the autoclave at a pressure of 29-55 psig while the content is stirred and 
heated to 27.degree.-92.degree. for a total of thirteen hours. Residual 
excess hydrogen is removed from the reaction mixture by evacuation and 
purging with nitrogen four times. The reaction mixture is then filtered 
through diatomaceous earth and the filtrate stripped to provide an oil 
solution of the desired amino phenol. This solution contains 0.578% 
nitrogen. 
EXAMPLE 2 
A mixture of 906 parts of an oil solution of an alkyl phenyl sulfonic acid 
(having an average molecular weight of 450, vapor phase osmometry), 564 
parts mineral oil, 600 parts toluene, 98.7 parts magnesium oxide and 120 
parts water is blown with carbon dioxide at a temperature of 
78.degree.-85.degree. for seven hours at a rate of about 3 cubic feet of 
carbon dioxide per hour. The reaction mixture is constantly agitated 
throughout the carbonation. After carbonation, the reaction mixture is 
stripped to 165.degree./20 tor and the residue filtered. The filtrate is 
an oil solution of the desired overbased magnesium sulfonate having a 
metal ratio of about 3. 
EXAMPLE 3 
A polyisobutenyl succinic anhydride is prepared by reacting a chlorinated 
poly(isobutene) (having an average chlorine content of 4.3% and an average 
of 82 carbon atoms) with maleic anhydride at about 200.degree.. The 
resulting polyisobutenyl succinic anhydride has a saponification number of 
90. To a mixture of 1,246 parts of this succinic anhydride and 1000 parts 
of toluene there is added at 25.degree. 76.6 parts of barium oxide. The 
mixture is heated to 115.degree. C. and 125 parts of water is added 
drop-wise over a period of one hour. The mixture is then allowed to reflux 
at 150.degree. C. until all the barium oxide is reacted. Stripping and 
filtration provides a filtrate having a barium content of 4.71%. 
EXAMPLE 4 
A mixture of 1500 parts of chlorinated poly(isobutene) (of molecular weight 
of about 950 and having a chlorine content of 5.6%), 285 parts of an 
alkylene polyamine having an average composition corresponding 
stoichiometrically to tetraethylene pentamine and 1200 parts of benzene is 
heated to reflux. The mixture's temperature is then slowly increased over 
a 4-hour period to 170.degree. while benzene is removed. The cooled 
mixture is diluted with an equal volume of mixed hexanes and absolute 
ethanol (1:1). This mixture is heated to reflux and a 1/3 volume of 10% 
aqueous sodium carbonate is added to it. After stirring, the mixture is 
allowed to cool and the phases separated. The organic phase is washed with 
water and stripped to provide the desired polyisobutenyl polyamine having 
a nitrogen content of 4.5%. 
EXAMPLE 5 
A mixture of 140 parts of toluene and 400 parts of a polyisobetenyl 
succinic anhydride (prepared from the poly(isobutene) having a molecular 
weight of about 850, vapor phase osmometry) having a saponification number 
of 109 and 63.6 parts of an ethylene amine mixture having an average 
composition corresponding in stoichiometry to tetraethylene pentamine, is 
heated to 150.degree. C. while the water/toluene azeotrope is removed. The 
reaction mixture is then heated to 150.degree. C under reduced pressure 
until toluene ceases to distill. The residual acylated polyamine has a 
nitrogen content of 4.7%. 
EXAMPLE 6 
To 1,133 parts of commercial diethylene triamine heated at 
110.degree.-150.degree. is slowly added 6820 parts of isostearic acid over 
a period of two hours. The mixture is held at 150.degree. for one hour and 
then heated to 180.degree. over an additional hour. Finally, the mixture 
is heated to 205.degree. over 0.5 hour; throughout this heating, the 
mixture is blown with nitrogen to remove volatiles. The mixture is held at 
205.degree.-230.degree. for a total of 11.5 hours and then stripped at 
230.degree./20 tor to provide the desired acylated polyamine as a residue 
containing 6.2% nitrogen. 
EXAMPLE 7 
To a mixture of 50 parts of a polypropyl-substituted phenol (having a 
molecular weight of about 900, vapor phase osmometry), 500 parts of 
mineral oil (a solvent refined paraffinic oil having a viscosity of 100 
SUS at 100.degree. F.) and 130 parts of 9.5% aqueous dimethylamine 
solution (equivalent to 12 parts amine) is added drop-wise, over an hour, 
22 parts of a 37% aqueous solution of formaldehyde (corresponding to 8 
parts aldehyde). During the addition, the reaction temperature is slowly 
increased to 100.degree. and held at that point for three hours while the 
mixture is blown with nitrogen. To the cooled reaction mixture is added 
100 parts toluene and 50 parts mixed butyl alcohols. The organic phase is 
washed three times with water until neutral to litmus paper and the 
organic phase filtered and stripped to 200.degree./5-10 tor. The residue 
is an oil solution of the final product containing 0.45% nitrogen. 
EXAMPLE 8 
A mixture of 140 parts (by weight) of a mineral oil, 174 parts of a 
poly(isobutene) (molecular weight 1000)-substituted succinic anhydride 
having a saponification number of 105 and 23 parts of isostearic acid is 
prepared at 90.degree. C. To this mixture there is added 17.6 parts of a 
mixture of polyalkylene amines having an overall composition corresponding 
to that of tetraethylene pentamine at 80.degree.-100.degree. C. throughout 
a period of 1.3 hours. The reaction is exothermic. The mixture is blown at 
225.degree. C. with nitrogen at a rate of 5 pounds per hour for 3 hours 
whereupon 47 parts of an aqueous distillate is obtained. The mixture is 
dried at 225.degree. C. for 1 hour, cooled to 110.degree. C. and filtered 
to provide the desired final product in oil solution. 
The lubricating oils in which the nitrogen-containing additive combinations 
of this invention are useful can be of synthetic, animal, vegetable or 
mineral (e.g., petroleum) origin. Ordinarily, mineral oils are used 
because of their availability, general utility and low cost. In certain 
applications oils belonging to one of the other three classes may be used. 
For example, synthetic polyester oils (e.g., didodecyl adipate and 
pentaerythritol tetracaprylate) are often used, especially in jet engine 
lubrication. Mixtures of oils within one of the four classes or between 
such classes can often be used. Generally, the lubricating oils used will 
be fluid oils ranging in viscosity from about 40 SUS (Saybolt Universal 
Seconds) at 37.5.degree. to 200 SUS at 99.degree.. The additive 
combinations of this invention are normally used in an amount ranging from 
0.5 to about 30 parts by weight combination per hundred parts of oil. 
This invention also contemplates the use of other additives in the 
lubricating oil compositions of this invention. These other additives 
include such conventional additive types as anti-oxidants, extreme 
pressure agents, corrosion-inhibiting agents, pour point depressants, 
color stabilizing agents, anti-foam agents, and other such additive 
materials known generally to those skilled in the art of formulating 
lubricating oil compositions. 
As noted hereinabove, the nitrogen-containing compositions of this 
invention are particularly useful in formulating novel lubricating oils 
for use in two-cycle engines. In general, the two-cycle engine lubricating 
oil compositions of this invention contain about 98 to about 50% oil or 
mixture of oils of lubricating viscosity. Typical compositions contain 
about 90 to about 60% oil. The presently preferred oils are mineral oils 
and mineral oil-synthetic polymer and/or synthetic ester oil mixtures. 
Polybutenes of molecular weights of about 250 to about 1,000 (as measured 
by vapor phase osmometry) and fatty acid ester oils of polyols such as 
pentaerythritol and trimethylol propane are typical synthetic oils used in 
preparing these two-cycle oils. 
These oil compositions contain about 2 to about 30%, typically about 5 to 
about 20%, of at least one amino phenol as described hereinabove and about 
1 to about 30%, typically 2 to about 20% of at least one 
detergent/dispersant. The ratio (by weight) of amino phenol to 
detergent/dispersant in these oils varies between about 1:10 to about 
10:1. Other additives such as viscosity index (VI) improvers, lubricity 
agents, anti-oxidants, coupling agents, pour point depressing agents, 
extreme pressure agent, color stabilizers and anti-foam agents can also be 
present. 
Polymeric VI improvers have been and are being used as bright stock 
replacement to improve lubricant film strength and lubrication and/or to 
improve engine cleanliness. Dye may be used for identification purposes 
and to indicate whether a two-cycle fuel contains lubricant. Coupling 
agents such as organic surfactants are incorporated into some products to 
provide better component solubilities and improved fuel/lubricant mix 
water tolerance. 
Anti-wear and lubricity improvers, particularly sulfurized sperm oil 
substitutes and other fatty acid and vegetable oils, such as castor oil, 
are used in special applications, such as racing and for very high 
fuel/lubricant ratios. Scavengers or combustion chamber deposit modifiers 
are sometimes used to promote better spark plug life and to remove carbon 
deposits. Halogenated compounds and/or phosphorus-containing materials may 
be used for this application. 
Rust and corrosion inhibitors of all types are and may be incorporated into 
two-cycle oil formulations. Odorants or deodorants are sometimes used for 
aesthetic reasons. 
Lubricity agents such as synthetic polymers (e.g., polyisobutene having a 
number average molecular weight in the range of about 750 to about 
15,000), as measured by vapor phase osmometry or gel permeation 
chromatography, polyol ether (e.g., poly(oxyethylene-oxypropylene)ethers) 
and ester oils (e.g., the ester oils described above) can also be used in 
the oil compositions of this invention. Natural oil fractions such as 
bright stocks (the relatively viscous products formed during conventional 
lubricating oil manufacture from petroleum) can also be used for this 
purpose. They are usually present in the two-cycle oil in the amount of 
about 3 to about 20% of the total oil composition. 
Diluents such as petroleum naphthas boiling at the range of about 
38.degree.-90.degree. (e.g., Stoddard solvent) can also be included in the 
oil compositions of this invention, typically in an amount of 5 to 25%. 
Table 1 describes several illustrative two-cycle engine oil lubricant 
compositions of this invention. 
TABLE 1 
______________________________________ 
TWO-CYCLE ENGINE OIL BLENDS 
______________________________________ 
Amino.sup.2 
Phenol of Detergent-Dispersant.sup.2 
Oil.sup.1 
Example Example 1 Example Amount Amount, pbw 
______________________________________ 
A 6 2 2 92 
B 3 2 1 96 
C 10.6 6 2.1 87.3 
D 7.5 4 3.5 89 
E 6 3 2 92 
F 15 5 3 82 
______________________________________ 
.sup.1 The same base oil is used in each blend; this oil is a 650 neutral 
solvent extracted paraffinic oil cut with 20 percent by volume Stoddard 
solvent and containing 9 pbw per hundred parts of final blend of a bright 
stock having a viscosity of 150 SUS at 100.degree. F. 
.sup.2 Part by weight of the oil solution described in the indicated 
Examples. 
In some two-cycle engines the lubricating oil can be directly injected into 
the combustion chamber along with the fuel or into the fuel just prior to 
the time the fuel enters the combustion chamber. The two-cycle lubricants 
of this invention can be used in this type of engine. 
As is well known to those skilled in the art, two-cycle engine lubricating 
oils are often added directly to the fuel to form a mixture of oil and 
fuel which is then introduced into the engine cylinder. Such 
lubricant-fuel oil mixtures are within the scope of this invention. Such 
lubricant-fuel blends generally contain per 1 part of oil about 15-250 
parts fuel, typically they contain 1 part oil to about 50-100 parts fuel. 
The fuels used in two-cycle engines are well known to those skilled in the 
art and usually contain a major portion of a normally liquid fuel such as 
hydrocarbonaceous petroleum distillate fuel (e.g., motor gasoline as 
defined by ASTM Specification D-439-73). Such fuels can also contain 
non-hydrocarbonaceous materials such as alcohols, ethers, organo-nitro 
compounds and the like (e.g., methanol, ethanol, diethyl ether, methyl 
ethyl ether, nitromethane) are also within the scope of this invention as 
are liquid fuels derived from vegetable or mineral sources such as corn, 
alfalfa, shale and coal. Examples of such fuel mixtures are combinations 
of gasoline and ethanol, diesel fuel and ether, gasoline and nitromethane, 
etc. Particularly preferred is gasoline, that is, a mixture of 
hydrocarbons having an ASTM boiling point of 60.degree. C. at the 10% 
distillation point to about 205.degree. C at the 90% distillation point. 
Two-cycle fuels also contain other additives which are well known to those 
of skill in the art. These can include anti-knock agents such as 
tetra-alkyl lead compounds, lead scavengers such as halo-alkanes (e.g., 
ethylene dichloride and ethylene dibromide), dyes, cetane improvers, 
antioxidants such as 2,6-di-tertiary-butyl-4-methylphenol, rust 
inhibitors, such as alkylated succinic acids and anhydrides, 
bacteriostatic agents, gum inhibitors, metal deactivators, demulsifiers, 
upper cylinder lubricants, anti-icing agents and the like. 
An example of a lubricant-fuel composition encompassed by this invention is 
a blend of motor gasoline and the lubricant blend described above in 
Example C in ratio (by weight) of 50 parts gasoline to 1 part lubricant. 
Concentrates containing the nitrogen-containing compositions of this 
invention are also within the scope of this invention. These concentrates 
usually comprise about 20 to about 80% of one or more of the hereinabove 
described oils and about 20 to about 80% of one or more 
nitrogen-containing compositions. As will be readily understood by those 
skilled in the art, such concentrates can also contain one or more of the 
hereinabove described auxiliary additives of various types. Illustrative 
of these inventive concentrates are the following: 
EXAMPLE G 
A concentrate for treating 2-cycle engine oils is prepared by blending at 
room temperature 78.2 parts of the oil solution described in Example 1 
with 21.8 parts of the oil solution described in Example 7. 
EXAMPLE H 
A concentrate for treating 2-cycle engine oils is prepared by heating with 
mild agitation a mixture of 83.4 parts of the oil solution described in 
Example 1 with 16.6 parts of the oil solution described in Example 6 to 
110.degree. over a period of 0.5 hour.