WATER-BASED HYDRAULIC FLUID

FLUIDE D'HYDRAULIQUE A BASE D'EAU

English Abstract

Abstract of the Disclosure
Water-based hydraulic fluid for use in
industrial hydraulic systems comprising (1) a
polyether-based thickener, (2) a lubricant modifier(3)
a dispersant, (4) an EP additive, and (5) water.
Preferably, the thickener is a polyether polyol capped
with an alpha olefin oxide; the lubricant modifier is a
combination of a hydrocarbon oil, a fatty alcohol and a
glycol; the dispersant is the reaction product of an
alkenyl succinic anhydride and a dialkyl alkanolamine,
and the EP additive is a dialkyl dithiophosphate.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A high water-based hydraulic fluid in the form of an
oil-in-water emulsion comprising (1) from about 1.5 to about 15%
of a polyether-based thickener, (2) from about 0.5 to about 20% of
a liquid lubricant modifier which enhances the lubricating
properties of the hydraulic fluid and functions as a plasticizer
to prevent the formation of tacky deposits in hydraulic systems in
which the hydraulic fluid is employed, (3) from about 0.5 to about
5.0% of a dispersing agent which is the reaction product of an
alkenyl succinic anhydride or acid and a water soluble active
hydrogen compound, (4) from about 0.125 to about 1.25% of an
extreme pressure additive comprising a dialkyl or diaryl
dithiophosphate, or a dialkyl or diaryl dithiocarbamate, and (5)
at least 80% of water, said percentages being by weight based on
the total weight of the fluid.
2. A hydraulic fluid according to claim 1 in which said
thickener comprises a polyether polyol prepared by reaction
ethylene oxide and at least one lower alkylene oxide having 3 to 4
carbon atoms with at least one active hydrogen compound initiator
to prepare a heteric or block copolymer, and further reacting said
copolymer with at least one alpha olefin oxide, said polyol having
a molecular weight of from about 7,000 to 15,000.
3. A hydraulic fluid according to claim 2 in which said
active hydrogen compound is a diol or polyol.
4. A hydraulic fluid according to claim 2 in which said
33

active hydrogen compound is an aliphatic monohydric alcohol
containing from 4 to 30 carbon atoms.
5. A hydraulic fluid according to claim 1 in which said
thickener comprises a polyether polyol prepared by reacting a diol
or polyol, ethylene oxide and at least one lower alkylene oxide
having 3 to 4 carbon atoms to form a heteric or block copolymer,
said copolymer having a molecular weight of from about 7,000 to
75,000.
6. A hydraulic fluid according to claim 3 in which said
thickener comprises a polyether polyol prepared by reacting
ethylene oxide and propylene oxide with a lower glycol or polyol
to form a block copolymer, and further reacting said copolymer
with an alpha olefin oxide containing from 12 to 30 aliphatic
carbon atoms, said polyether polyol having a molecular weight of
from about 7,000 to 15.000.
7. A hydraulic fluid according to claim 4 in which said
thickener comprises a polyether polyol prepared by reacting
ethylene oxide. propylene oxide and an aliphatic alcohol
containing 12 to 18 aliphatic carbon atoms to form a block
copolymer, and further reacting said block copolymer with an alpha
olefin oxide containing from about 12 to 30 aliphatic carbon
atoms, said polyether polyol having a molecular weight of from
about 7,000 to 15,000.
8. A hydraulic fluid according to claim 6 or 7 in which said
active hydrogen compound is ethylene glycol.
9. A hydraulic fluid according to claim 1 in which said
34

lubricant modifier is selected from the group consisting of
aliphatic hydrocarbons, cycloaliphatic hydrocarbons, aromatic
hydrocarbons, mineral oils, silicone oils, synthetic hydrocarbon
oils, glycerides, fatty alcohols, condensation products of fatty
acids and alkanolamines, phosphate-modified condensation products
of fatty acids and alkanolamines, ethoxylated fatty amines,
glycols, polyglycols, ethoxylated vegetable oils, ethoxylated
fatty amides, organic esters, triaryl phosphate esters and
polyphenyl ethers, and mixtures thereof.
10. A hydraulic fluid according to claim 9 in which said
lubricant modifier comprises a polybutene having a viscosity of
about 400 SUS at 100°F.
11. A hydraulic fluid according to claim 9 in which said
lubricant modifier is a phosphate-modified condensation product of
a fatty acid and a dialkanolamine.
12. A hydraulic fluid according to claim 9 in which said
lubricant modifier is a light lubricating oil of the naphthenic
type having a viscosity of about 100 SUS at 100°F.
13. A hydraulic fluid according to claim 9 in which said
lubricant modifier is ethylene glycol.
14. A hydraulic fluid according to claim 9 in which said
lubricant modifier is a monobutyl ether of
poly(oxyethylene-oxy-1,2-propylene) glycol having a molecular
weight of from about 1,500 to 4,000.
15. A hydraulic fluid according to claim 9 in which said
lubricant modifier comprises a mixture of a phosphate-modified

condensation product of a fatty acid and a dialkanolamine, and a
monobutyl ether of poly(oxyethylene-oxy-1,2-propylene) glycol.
16. A hydraulic fluid according to claim 9 in which said
lubricant modifier comprises a mixture of a polybutene, a
polyglycol and a fatty alcohol.
17. A hydraulic fluid according to claim 9 in which said
lubricant modifier comprises a mixture of a mineral oil, a fatty
alcohol and a glycol.
18. A hydraulic fluid according to claim 9 in which said
lubricant modifier comprises a mixture of a fatty alcohol and a
glycol.
19. A hydraulic fluid according to claim 1 in which said
dispersing agent comprises the reaction product of an alkenyl
succinic anhydride or acid in which the alkenyl group contains
from 16 to 30 carbon atoms, and an alkyl alkanolamine of the
formula
<IMG>
in which R is hydrogen or an alkyl group containing from about 8
to 25 carbon atoms, R' is hydrogen (C2H4O)xH, or
(C3H6O)xH, R" is R or R' and x is an integer of from 2 to
50, said reaction product having a molecular weight of from about
800 to 2000.
20. A hydraulic fluid according to claim 19 in which said
dispersing agent comprises the reaction product of polyisobutenyl
succinic anhydride having a molecular weight of about 1,000 and
36

diethyl ethanolamine.
21. A hydraulic fluid according to claim 1 in which said
dispersing agent is an ester of an alkenyl succinic anhydride or
acid and ethoxylated castor oil.
22. A hydraulic fluid according to claim 1 in which said
dispersing agent is an ester of succinic anhydride or acid and an
ethoxylated fatty amine.
23. A hydraulic fluid according to claim 1 in which said
dispersing agent is the reaction product of succinic anhydride or
acid and a compound of the formulae
HO(Z)yOR'''
HO(Z)yRiv, or
<IMG>
in which Z is (C2H4O) or (C3H6O), R''' is an alkyl group
containing from 8 to 20 carbon atoms, RiV is -N-CO-R''',
-OCO-R''', <IMG> , or SR''', and y is an integer from 3 to 10.
24. A hydraulic fluid according to claim 1 in which said
extreme pressure additive has the formulae
<IMG>
in which Rv is an alkyl group containing from 4 to 16 carbon
atoms, phenyl or naphtyl, X is hydrogen, an amine, ammonium or
substituted ammonium, sodium, potassium, lithium, calcium,
37

magnesium, manganese or zinc, and a is an integer of from 1 to 2.
25. A hydraulic fluid according to claim 24 in which said
extreme pressure additive is a zinc dialkyl dithiophosphate.
26. A hydraulic fluid according to claim 24 in which said
extreme pressure additive is a zinc dialkyl dithiophosphate in
which the alkyl groups contain from about 4 to about 10 carbon
atoms.
27. A high water-based hydraulic fluid in the form of an
oil-in-water emulsion comprising (1) from about 2 to about 6% of a
thickener comprising a polyether polyol prepared by reacting
ethylene oxide, propylene oxide and a lower glycol or polyol to
form a block copolymer, and further reacting said block copolymer
with an alpha olefin oxide containing from about 12 to about 18
aliphatic carbon atoms, said polyether having a molecular weight
of from about 12,000 to about 14,000 (2) from about 1 to about 10%
of a liquid lubricant modifier which enhances the lubricating
properties of the hydraulic fluid and functions as a plasticizer
to prevent the formation of tacky deposits in hydraulic systems in
which the hydraulic fluid is employed, (3) from about 1 to about
3% of a dispersing agent comprising the reaction products of
polyisobutenyl succinic anhydride and diethyl ethanolamine said
reaction product having a molecular weight of about 1,000, (4)
from about 0.5 to about 0.75% of a zinc diakyl dithiophosphate in
which the alkyl groups contain from about 4 to about 10 carbon
atoms, and (5) at least 80% of water, said percentages being by
weight based on the total weight of the fluid.
38

28. A concentrate for forming a high water-based hydraulic
fluid as defined in claim 1 by addition of water thereto
comprising (1) from about 5 to 20% of a polyether-based thickener,
(2) from about 5 to about 40% of a lubricant modifier, (3) from
about 5 to about 20% of a dispersing agent which is the reaction
product of an alkenyl succinic anhydride or acid and a water
soluble active hydrogen compound, (4) from about 1 to about 10% of
an extreme pressure additive comprising a dialkyl or diaryl
dithiophosphate, or a dialkyl or diaryl dithiocarbamate, and (5)
balance water, said percentages being by weight based on the total
weight of the components (1) to (5).
29. A concentrate according to claim 28 in which said
thickener comprises a polyether polyol prepared by reacting
ethylene oxide and at least one lower alkylene oxide having 3 to 4
carbon atoms with at least one active hydrogen compound initiator
to prepare a heteric or block copolymer, and further reacting said
copolymer with at least one alpha olefin oxide, said polyol having
a molecular weight of from about 7,000 to 15,000.
30. A concentrate according to claim 29 in which said active
hydrogen compound is a diol or polyol.
31. A concentrated according to claim 29 in which said active
hydrogen compound is an aliphatic monohydric alcohol containing
from 4 to 30 carbon atoms.
32. A concentrate according to claim 28 in which said
thickener comprises a polyether polyol prepared by reacting a diol
or polyol, ethylene oxide and at least one lower alkylene oxide
39

having 3 to 4 carbon atoms to form a heteric or block copolymer,
said copolymer having a molecular weight of from about 7,000 to
75,000.
33. A concentrate according to claim 29 in which said
thickener comprises a polyether polyol prepared by reacting
ethylene oxide and propylene oxide with a lower glycol or polyol
to form a block copolymer, and further reacting said copolymer
with an alpha olefin oxide containing from 12 to 30 aliphatic
carbon atoms, said polyether having a molecular weight of from
about 7,000 to 15,000.
34. A concentrate according to claim 31 in which said
thickener comprises a polyether prepared by reacting ethylene
oxide, propylene oxide and an aliphatic alcohol containing 12 to
18 aliphatic carbon atoms to form a block copolymer, and further
reacting said block copolymer, and further reacting said block
copolymer with an alpha olefin oxide containing form about 12 to
30 aliphatic carbon atoms, said polyether having a molecular
weight of from about 7,000 to 15,000.
35. A concentrate according to claim 28 in which said active
hydrogen compound is ethylene glycol.
36. A concentrate according to claim 28 in which said
lubricant modifier is selected from the group consisting of
aliphatic hydrocarbons, cycloaliphatic hydrocarbons, aromatic
hydrocarbons, mineral oils, silicone oils, synthetic hydrocarbons
oils, glycerides, condensation products of fatty acids and
alkanolamines, phosphate-modified condensation products of fatty

acids and alkanolamines, ethoxylated fatty amines, ethoxylated
vegetable oils, ethoxylated fatty amides, organic esters, glycols,
polyglycols, triaryl phosphate esters and polyphenyl ethers.
37. A concentrate according to claim 36 in which said
lubricant modifier comprises a polybutene having a viscosity of
about 400 SUS at 100°F.
38. A concentrate according to claim 36 in which said
lubricant modifier is a phosphate-modified condensation product of
a fatty acid and a dialkanolamine.
39. A concentrate according to claim 28 in which said
lubricant modifier is a light lubricating oil of the naphthenic
type having a viscosity of about 100 SUS at 100°F.
40. A concentrate according to claim 28 in which said
lubricant modifier is ethylene glycol.
41. A concentrate according to claim 28 in which said
lubricant modifier is a monobutyl ether of poly
(oxyethylene-oxy-1,2-propylene) glycol having a molecular weight
of from about 1,500 to 4,000.
42. A concentrate according to claim 28 in which said
lubricant modifier comprises a mixture of a phosphate modified
condensation product of a fatty acid and a dialkanolamine, and a
monobutyl ether of poly(oxyethylene-oxy-1,2-propylene) glycol.
43. A concentrate according to claim 28 in which said
lubricant modifier comprises a mixture of a polybutene, a
polyglycol and a fatty alcohol.
44. A concentrate according to claim 28 in which said
41

lubricant modifier comprises a mixture of a mineral oil, a fatty
alcohol and a glycol.
45. A hydraulic fluid according to claim 28 in which said
lubricant modifier comprises a mixture of a fatty alcohol and a
glycol.
46. A concentrate according to claim 28 in which said ester
of succinic anhydride or acid comprises the reaction product of an
alkenyl succinic anhydride or acid in which the alkenyl group
contains from 16 to 30 carbon atoms, and an alkyl alkanolamine of
the formula
<IMG>
in which R is hydrogen or an alkyl group containing from about 8
to 25 carbon atoms, R' is hydrogen (C2H4O)XH or
(C3H6O)X H, R" is R or R' and x is an integer of from 2 to
50.
47. A concentrate according to claim 46 in which said ester
of succinic anhydride comprises the reaction product of
polyisobutenyl succinic anhydride having a molecular weight of
about 1,000 and diethyl ethanolamine.
48. A concentrate according to claim 28 in which said
dispersing agent is an ester of an alkenyl succinic anhydride or
acid and ethoxylated castor oil.
49. A concentrate according to claim 28 in which said
dispersing agent is an ester of succinic anhydride or acid and an
ethoxylated fatty amine.
42

50. A concentrate according to claim 28 in which said
dispersing agent is the reaction product of succinic anhydride or
acid and a compound of the formulae
HO(Z)yOR'''
HO(Z)yRiv, or
<IMG>
in which Z is (C2H4O) or (C3H6O), R''' is an alkyl group
containing from 8 to 20 carbon atoms, R is -N-CO-R''',
-O-CO-R''', <IMG> , or SR''', and y is an integer from 3 to 10.
51. A concentrate according to claim 28 in which said extreme
pressure additive has the formulae
<IMG>
in which Rv is an alkyl group containing from 4 to 16 carbon
atoms, phenyl or naphtyl, X is hydrogen, an amine, ammonium or
substituted ammonium, sodium, potassium, lithium, calcium,
magnesium, manganese or zinc, and a is an integer of from 1 to 2.
52. A concentrate according to claim 51 in which said extreme
pressure additive is a zinc dialkyl dithiophosphate.
53. A concentrate according to claim 51 in which said extreme
pressure additive is a zinc dialkyl dithiophosphate in which the
alkyl groups contain from about 4 to about 10 carbon atoms.
43

54. A concentrate for forming a high water-based hydraulic
fluid as claimed in claim 28 by the addition of water thereto,
said concentrate comprising (13 from about 12 to about 18% of the
thickener, (2) from about 10 to about 20% of the lubricant
modifier, (3) from about 10 to about 15% of the dispersing agent,
(4) from about 2 to about 6% of a zinc dialkyl dithiophosphate in
which the alkyl groups contain from about 4 to about 10 carbon
atoms, and (5) balance water, said percentages being by weight
based on the total weight of the component, (1) to (5).
44

Description

~æ~2431
~ hls inventlon relates to an lmproved hlgh
wa~er_based hydraullc fluld partlcularly sultable for
use ln lndustrlal hydraullc system3.
The technology Or power transmi~310n by means
Or a hydraullc fluld 19 well establlshed. Varlous
non-compre3slble fluld~ such as water and oll have been
u3ed a~ hydraullc rluld3. Petroleum oils have certain
advantages over water as hydraullc rlulds ln that they
reduce wear and lnhlblt rust rormation ln hydraullc
s) tem co0ponents such as pumps, and exhlblt a hlgher
vl~coslty than water, thu~ providlng ror reduoed fluld
leakage. Unfortunately, a maJor deflclency Or
petroleum oils ls rlammability. They are al~o
sen~ltlve to the lntruslon Or water lnto hydraullc
systems ln whlch they are employed. In addltlon,
dl~po3al Or ~pent petroleum oil-based hydraullc flulds
preqents ecologlcal proble~s.
In recent years, by reason Or thelr low cost,
e~rort~ have been made to provlde water-based hydraulic
rluld~ o~ lmproved propertles, such a3 enhanced
antl_wear propertles. One suggestlon has been to
lnclude ln an aqueou~ based hydraullc fluld an extie~e
pressure (EP) addltive, such a3 a dithlophoYphate,
along ulth a disperslng agent, becauqe of the
sub~tantlal water in~olublllty Or quch EP addltlves.
A1so, by reaYon Or the substantlally lower viYcosity of
water-ba~ed hydraulic rluld3 the lncluslon therein of
varlou3 type~ Or thlckeners ha3 been 3ugge~ted.
However, varlous Or ~uch thlckeners hav~ evldenced
shear lnstablllty re3ultlng ln slgnlficant vlsco~lty
~''

reduction of aqueous-based hydraulic fluids containing
such thickeners.
This invention relates to thickened, high
viscosity, high water-based hydraulic fluids of the
oil-in-water emulsion type. By the the term "high
water-based hydraulic fluids" is meant compositions
comprising about 80~ or more, by weight, of water. In
addition to water, the hydraulic fluids of this
invention contain as essential constituents (l) a
polyether-based thickener, (2) a lubricant modifier,
(3) a dispersant, and (4) an EP additive, all in
specified proportions. Optionally, the hydraulic
fluids of the invention may contain various
; emulsifiers, corrosion inhibitors, defoamers, coupling
agents, freezing point depressants, and the like,
depending upon the particular hydraulic system in which
the hydraulic fluid is to be employed. Advantageously,
the essential constituents of the hydraulic fluid may
be combined to form a concentrate which is readily
dilutable with water to provide a hydraulic fluid.
The high water-based hydraulic fluids of this
invention provide improvements over prior known
aqueous-based hydraulic fluids in the nature of more
stable viscosity characteristics, reduced wear and
better lubrication.
A high water-based hydraulic fluid according
to the present invention can be obtained by blending
together at a temperature of about 120-180F.
(~9o-820C.), the lubricant modifier and dispersing
agent, following which, after removal from heat, the EP

additive is introduced to the blend. ~ater is then
added and a uniform clear fluid is obtained. This
clear fluid is then combined with the thickener, and
additional water is added to provide a hydraulic fluid
having the desired water content and viscosity. The
optional constituents such as defoamers, corrosion
inhibitors, etc. may be added at an appropriate time
during preparation oP the fluid.
Concentrates of the invention can be blended
with a substantial amount of water to provide
fire-resistant hydraulic fluids of improved lubricity
and anti-wear characteristics, and of stable viscosity.
Even at water concentrations in excess of 80~, by
weight, the hydraulic fluids of this invention can be
used effectively in systems containing vane pumps, and
can replace standard hydraulic oils with reductions in
cost.
In accordance with this invention, there are
provided high water-based hydraulic fluids andl
concentrates which can be diluted with water to form
such hydraulic fluids comprising (1) a polyether-based
thickener, (2) a lubricant modifier, (3) a dispersant,
(4) an EP additi-re, and (5) water. As is conventional,
corrosion inhibitors, defoamers, metal deactivators,
etc. may be included in the compositions. Such
hydraulic fluids were found to undergo little reduction
in viscosity in use.
The lubricant modifiers which may be used in
the novel hydraulic fluids of this invention include
water immiscible liquids and also water~miscible or

~2~
water soluble or dispersible liquids and mixtures of
such liquids. These lubricant modifiers enhance the
lubricating properties of the hydraulic fluids and also
function as plasticizers to prevent the formation of
tacky deposits in the hydraulic systems in which the
hydraulic fluids are employed. In addition, the
water-miscible or water dispersible fluids, such as the
alkylene glycols defined more fully hereinafter, at
higher concentrations, improve the fluidity and low
temperature properties of the hydraulic fluids.
The water immiscibla liquids which may be
used as lubricant modifiers include such liquids as
aliphatic, cycloaliphatic and aromatic hydrocarbons;
chlorinated hydrocarbons; mineral oils; silicone oils
such as a dimethyl and methyl phenyl silicones;
fatty materials such as vegetable oils, fish oils,
fatty acids, fatty alcohols condensation products of
fatty acids and alkanolamines, which may be
phosphate-modified; ethoxylated fatty amides, fatty
alcohols, fatty acids, vegetable oil and fatty amines;
organic esters such as di-2-ethylhexyl sebacate or
azelate, and trimethylolpropane tricaprylate; glycols
and polyglycols; triaryl phosphate esters such as
triisopropyl phenyl phosphate; and polyphenyl ethers.
One group of preferred lubricant modifiers
are the synthetic hydrocarbon oils of lubricating
viscosity. Normally such oils, will range in viscosity
; from 50 to 700 Saybolt Universal Seconds (SUS) at 100F.
Such synthetic hydrocarbon oils are normally prepared
by polymerizing lower monoolefins in the presence of a

~LZ~Z43:8
suitable catalyst such as BF3 or AlC13. The lower
olefins include, for example, ethylene, propylene,
butylene, and the like. Other synthetic hydrocarbon
oils are poly alpha olefins and alkyl benzenes. Such
synthetic hydrocarbon fluids have adequate fluidity at
low temperatures.
The water immiscible lubricant modifiers may
comprise naturally occuring hydrocarbons such as
mineral oils which may be either parafinic or
naphthenic in nature. Such mineral oils should have a
viscosity of from about 50 to 700 SUS at 100F.
preferred mineral oil for use in the hydraulic fluids
of this invention is a light lubricating oil of the
naphthenic type having a viscosity of 80 to 200 SUS at
100F, a particularly preferred oil of this type having
a viscosity of 100 to 150 SUS at 100F.
Another group of preferred lubricant
modifiers are the condensation products of fatty acids
and alkanolamines. These products, which are water
dispersible, may be prepared by reacting a fatty acid
or fatty ester with an alkanolamine at temperatures on
the order of 100 to 160C. with removal of water of
condensation or aleohol. The mol ratio of fatty acid
or ester to amine may be in the range of from about 2:1
to about 1:3. Optionally, a small amount, e.g. 0.01 to
0.05 mols of phosphoric acid may be present during the
reaction.
The fatty acids used in the preparation of
the condensates generally should contain from 7 to 22,
preferably 12 to 18 carbon atoms and may be saturated

~Z~3~
or unsaturated, or a mlxture of both. Thuq, ~atty
ac~ds sultable rOr use ln pr¢parlng the condensate~
lnolude heptanolc, caprylic, pelargonic, capric,
lauric, myrlstlc, palmltlc, stearic, olelc and behenlc
acid~. A preferred fatty acid reactant i3 a mixture of
st lric and olelc acids.
Alkanolamines whlch have been found useful ln
preparing the conden~ate~ include ethanolamine,
isopropanolamlne, N-methyl ethanolamine,
diethanolamlne, dipropanolamine, dil~opropanolamine,
and triethanolamine. A particularly pre~erred
alkanolamine 19 dlethanolamlne.
Another group of prererred water
soluble/dlsperqlble lubrlcant modlrlers are the
ethoxylated fatty amldes, amines, alcohols and
ve~etable olls. The alkyl group Or these fatty
materlals generally should oontaln from 7 to 22,
preferably 12 to 18 carbon atoms. Such alkyl group~
lnclude heptanoyl, caprylyl, nonanoyl, capryl, lauryl,
~yrlstyl, stearyl, oleyl and behenyl. Such lubricant
modlflers may co~prlse the fatty material derlved from
vegetable olls, ~uch a~, palmltic, coconut, ca~tor,
rapeseed, ~oya bean" corn, peanut, sunflower oll, and
the like. In additlon such fatty materlal my be
derlved from anlmal fat like tallow, lard, flsh oll and
the llke.
The degree of ethoxylation of theqe water
soluble~dl~per~lble lubrlcant modifiers ~hould be
between 1 to 20 preferably 4 to 6 moles Or ethylene
oxide to one mole of fatty amlde, amine, alcohol or

vegetable oil.
A preferred group of lubricant modifiers
which are water soluble are the alkylene and poly
alkylene glycols having the formula RO(CnH2nO)xH, where
R is hydrogen or an alkyl group containing 1 to 10
carbon atoms, n is an integer from 2 to 6 and x is an
integer from 1 ko 70. The alkylene glycols include
ethylene and propylene glycol and their higher homologs
such as diethylene and dipropylene glycol. The
preferred alkylene glycol is ethylene glycol.
Suitable water miscible or water dispersible
polyoxyalkylene glycols include polyoxyethylene,
polyoxypropropylene and poly(oxyethylene, oxypropylene)
glycols having molecular weights of from about 200 to
about 4000. These polyglycols may be uncapped or
capped at the end by a lower alkyl group containing
from 1 to 10 carbon atoms. The weight percent of the
oxyethylene in the poly(oxyethylene, oxypropylene)
glycols should be on the order of at least about 20%.
A particular preferred polyglycol is the monobutyl
ether of poly (oxyalkylene-oxy-1,2-propylene) glycol
having a molecular weight of about 1500 to 4000.
Generally the lubricant modifiers will
comprise from about 0.50 to about 20% by weight of the
hydraulic fluid. Preferred hydraulic fluids of the
invention contain on the order of 1.0 to 10~ of
lubricant modifier.
The polyether-based thickeners used in the
hydraulic fluids of this invention are relatively high
molecular weight polyoxyalkylene compounds, also

~;~
re~erred to hereln a~ polyether polyol~, whlch may be
capped by means of an alpha ole~ln oxlde. The
thlckener~ are water-~oluble, or at lea~t
water-d1sperslble. The preferred thlckenerq are the
alpha olefln capped polyoxyethylene-polyoxypropylene
block copolymers contalnin~ on the order of about 20 to
35S, by welght, of 1,2-propylene oxide groups.
The polyether-ba~ed thickenera u~eful in the
water-ba~ed hydraullc fluld~ of thls invention are
prererably two types Or normally llquld polyether
polyol~. Each type 19 obtalned by reacting ethylene
oxlde, at lea3t one lower alkylene oxlde havlng 3 to 4
carbon atom~, and an actlve hydlrogen compound.
However, ln one type of thlckener, the active hydrogen
compound l~ an aliphatic alcohol having two or more
hydroxy groups ln the molecule, whlle ln the other type
.3 an allphatlc ~onohydric alcohol contalnlng from 4
to 30, preferably 12 to 18, carbon atomq in the
allphatic group. In elther lnstance, the~e polyether
polyols, whlch may be heterlc or block copolymers, may
be oapped by reactlon wlth an alpha olefln oxlde having
about 12 to 30, preferably 12 to 18 allphatlc carbon
atoms. However, tho~e thlckener~ ln whlch the actlve
hydrogen compound 19 a dlol or polyol may be u~ed ln
uncapped form, provlded they have a ~ufflclently high
molecular weight. Thus, such uncapped polyether
polyol~ ~hould have a molecular welght of at least
7,000 and may have a molecular welght a~ hlgh a~ 75,000.
Prercrred uncapped polyether polyol~ Or thlq type have
a molecular weight Or from about lO,000 to 30,000.
.. .. .. .

~3~
If the copolymer thickeners in which the
active hydrogen compound is a diol or polyol are capped
by reaction with an alpha olefin oxide, the molecular
weight thereof should be on the order of 7,000 to
15,000, preferably about 12,000 to 14,000. In either
instance, i.e. whether the polyether polyols are of
relatively high, 20,000 plus, molecular weight, or of
relatively low molecular weight, e.g. less than about
15,000, the weight percent of ethylene oxide groups
should be on the order of 25~ to ~0%. Preferably, the
copolymers contain about 20 to 35% of 1,2-propylene
oxide groups.
The diols used as the active hydrogen
containing compound in the reaction may be glycols,
such as ethylene glycol, diethylene glycol and higher
glycols. The diols may also contain oxyalkylene groups.
Typical of the polyols which may be used as active
hydrogen compounds are glycerol, polyglycerol and
trimethylol propane.
In preparing these polyether polyols, good
results may be obtained by bringing a mixture
containing the ethylene oxide and the lower alkylene
oxide into intimate contact with the diol or polyol
starting compound in the liquid phase, throughout which
a suitable catalyst is uniformly dispersed. As
catalysts, sodium and potassium hydroxide are preferred.
The reaction is carried out at temperatures on the
order of 50 to 160C.
Such polyether polyols in which the active
hydrogen compound is a diol and the process for their

43~
preparation ace described in detail in U.S. Pat. No.
2,~25,845.
~ s noted above, the polyether polyol6 which
contain a diol o~ polyol may either be used as such,
or capped with an alpha olefin oxide.
Advantageously, it was di6covered that a
~ubstantially lesser amount of the capped polyol,
whe~her including a diol or polyol, or aliphatic
monohydric alcohol as the active hydrogen-containing
compound, a6 compared to an uncapped polyol, could be
u6ed to provide a hydraulic fluid of a given
viscosity. Thus, for example, in the hydraulic
fluids of thi6 invention, 4.8 parts by weight of a
capped thickener were found to provide a hydraulic
fluid with a viscosity of 190-200 SUS at 100F., as
compared to a visco~ity of only 75-80 SUS using 12.5
parts of an uncapped thickener (cf. Examples I and II
infra).
~s previously stated, the alpha olefin
oxideg utilized to modify or cap the polyether
polyols are those containing about 12 to 30,
pre~erably abou~ 12 to 18 aliphatic carbon atoms, and
mixtuees thereof. The amount of alpha olefin oxide
required to obtain the desired thickeners is about 1
to about 20~, by weight of the total weight of the
capped thickeners.
The capped reaction may be carried out by
adding the alpha olefin oxide to the polyether
polyol, a liquid, and heating the mixture to a
temperature of about 50 ~o 90 C. for about 1 to
Z hours, depending upon batch ~ize. Befoee addition
,, ~,

~æ~
of alpha olefin oxide, it is desirable to render the
polyether polyol as anhydrous as po~sible.
A second type of preferLed thickeners are
those heteric or block copolymer6 of ethylene oxide,
a lower alkylene oxide and an active hydrogen com~,und
which prefeLably i6 an aliphatic monohydroxy alcohol
containing 4 to 30, preferably 12 to 18 aliphatic
carbon atoms, capped with an alpha olefin oxide which
also contains lZ to 30 aliphatic carbon atoms. Such
thickeners and method5 for their ~reparation are
disclosed in V.S. Pat. No. 4,288,639.
Typical of the preferred monohydric
alcohols for reaction with ethylene oxide and a lower
alkylene oxide are butyl alcohol, capryl alcohol,
lauryl alcohol, myristyl alcohol, stearyl alcohol,
cetyl alcohol and behenyl alcohol. The reaction may
be carried out usinq well known alkaline
oxyalkylation catalysts, for example, strong bases
such as sodium and potassium hydroxides. The!
reaction can be cacried out in the pre6ence of an
inert organic solvent, examples of which include
aliphatic hydrocarbons such as hexane and heptane;
aromatic hydrocarbons, such as benzene and toluene;
chloEinated hydrocarbons such as ethylene dichloride,
and the like. Reaction temperatures are as stated
above, i.e. on the order of 50 to 160C.
Preparation of the latter ~olye~her polyols
: i8 well known in the art. Further details of
preparation of heteric copolymer~ of lower alkylene
30 oxides are disclosed in U.S. Pat. No. 3,829,506,

~243~
incorporated herein by reference. Additional
information on preparation of block copolymer~ of
lower alkylne oxide6 is to be found in U.S. Pat. No.
3,535,307.
The polyether polyols in which the active
hydrogen compound is an aliphatic monohydcic alcohol
may be capped with an alpha olefin oxide as de6cribed
herein above.
The molecular weight of the latter
di6cus6ed capped thickeners should be in the range of
about 7,000 to 15,000, preferably 12,000 to 14,000.
Other polyether polyols which may be capped
to provide thickeners according to this invention and
methods for their preparation are di6closed in U.S.
Pat. No6. 2,425,755, 3,036,118, 3,595,924, 3,706,714,
and 3,829,505; and British Patents NOB . 950,844 and
1,228,561.
In the hydraulic fluids oE thi6 invention, the
thickeners will generally comprise from about 1.5 to
about 15%, by weight, the optimum amount depending upon
the particular thickener employed and the viscosity
which i6 desired for the hydraulic fluid. As noted
above, the capped thickeners have greater thickening
power than do the uncapped thickeners. Thus, le66er
amounts of the capped thickener6 can be used to provide
the hydraulic fluids o~ the invention with a desired
vi~cosity. Preferably, the hydraulic fluids contain
on the average of about 2 to 6% of capped thickeners
or 10 to 15% of uncapped thickeners. By using the

preferred quantities of thickeners, the hydraulic
fluids will have viscosities in the range of about 50
to about 200 SUS at 100F.
Useful dispersing agents for inclusion in the
hydraulic fluids of this invention are reaction
products of an alkenyl succinic anhydride (or acid)
with certain water-soluble active hydrogen compounds,
an example of which is dialkyl alkanolamine. These
dispersing agents are particularly effective in
dispersing oil-soluble extreme pressure (EP) additives,
such as zinc dialkyl dithiophosphate, in the aqueous
fluid where it can act as an anti-wear constituent and
provide EP properties.
; The alkenyl succinic anhydride (or acid) with
which the active hydrogen compound is reacted may be
prepared by reacting maleic anhydride with a long chain
alpha olefin by conventional procedures. The olefin
may be reacted with maleic anhydride (or acid) at
temperatures of 150-250C., the amount of olefin used
being at least the stoichiometeric equivalent of the
maleic anhydride reactant. A preferred olefin reaction
product is a polyisobutene of sufficient chain length
to provide the succinic anhydride reaction product with
a molecular weight on the order of 500 to 2000)
preferably about 800 to 1200, a molecular weight of
about l,000 being particularly preferred.
As to the other reactant, it is an active
hydrogen compound and may be an alkyl alkanolamine
having the formula

R-I~R''
R 7
in which R is hydrogen or an alkyl group containing
from 8 to 2l1 carbon atoms, R' is hydrogen or ~C2H40)XH
or (C3H60)XH, R" is R or R', and x is an integer of
from 1 to 50. ~ particularly preferred alkyl
alkanolamine reactant is diethylethanolamine.
Other active hydrogen compounds for reacting
with the alkenyl succinic anhydride (or acid) have the
formulae
HO(Z)yOR~
HO(Z)yRiV,or
HO(Z)y ~ ~O ~ -R"'
in which Z is (C2H40) or (C3H60), R"' is an alkyl group
RVO
1 11
containing from 8 to 20 carbon atoms, RiV is -N-C-R"',
-O-C-R"', -O- ~ -R"', or SR"', RV is R' or an alkyl
group containing from 1 to 4 carbon atoms, and y is an
integer from 3 to 10. Preferably, R"' is a C~ to C9
alkyl group and y is 5.
The alkenyl succinic anhydride (or acid) is
reacted with the active hydrogen compound at a
temperature of about 50 to 250C., preferably 600 to
150C. for a time sufficient to form the desired
reaction product, usually from 1 to 6 hours. The
relative amounts of anhydride and active hydrogen
compound can vary somewhat, but preferably two mols of
such compound are used with each mol of anhydride to
ensure complete reaction of the anhydride.
14

The hydraulic fluid should contain on the
order of from about 0.5 to about 5.0%, preferably 1
to 3%, of the dispersing agent in order to ensure
proper dispersion of the EP additive and othe~
water-insoluble constituents in the aqueous phase of
the insoluble fluid.
The extreme pressure (EP) additives used in
hydraulic fluids of the invention are dialkyl ~r
diaryl dithiophosphates or dithiocarbamates,
preferably of the re6pective formulae
~Y---o ~ 5 ] X and ~ ~ C - S -
where Rv is an alkyl group containing feom 4 to 16,
preferably 4 to 10 carbon atoms, phenyl or naphthyl,
and X is hydrogen, an amine, ammonium, a substituted
ammonium compound, a metal of Group I or II of the
Periodic Table, i.e. selected ~rom the alkali metals
such as sodium, eotassium or lithium, the alkaline
earth metals, u6ually magnesium OL calcium, and the
Group II transition metals, such as manganese or
zinc, particularly zinc, which is preferred,
antimony, or Mo2S202, and a is an integer of
from 1 to 2.
The dithiophosphates may be prepared by
reacting an alcohol with phosphorous pentasulfide at
a temperature of from 40 - 120C. for a period of 1
to 4 hours. Typical alcohols which may be used in the
reaction are such normal alcohols as n-butyl, n-heptyl,
n-octyl, n-~ecyl and n-dodecyllalcohol. Suitable

~ 33~
branched chain alcoholQ include 2-methyl-1-pentanol,
2-ethyl-l-hexanol and 2,2-dlmethyl-l-octanol.
An organic or lnorganlc ba~e may be reacted
~ with the dithiophosphate to form the EP addltlve3 for
inclu~lon ln the hydraulic fluid. Ashless
dithiophoqphates may be obtained by reactlon with
non-metallic ba~es sucn as amine~, ammonla and
substituted ammonlum compounds. Reactlon wlth metal
oxides or hydroxide~ producesashing dithiophoqphates
which usually are pre~erred by reason of thelr
propertle~.
The metals most u~ually used are those of
Groups I and II of the Perlodic Table, i.e. the alkali
metals, such aq sodium, potassium, and lithlum, the
alkaline earth metals, usually magne~ium or calclum,
and the Group II transition metals, particularly zinc,
which i~ especially preferred. The metal is generally
used in the form of lts oxide or hydroxide for reaction
wlth dlthiophosphorlc acld.
The reaction between the dlthiophosphorlc
acld and the base 19 usually conducted at a temperature
of 75 150C. over a period of 1-4 hours.
The EP additive ~hould be present in an
amount of from about 0.125 to 1 a 25~, preferably 0.5 to
0.75~, by weight.
The dithiocarbamates are well known compounds
and generally may be obtalned by reactlon of a suitable
amine and carbon disulfide.
In addltion to the above essential
constituent~ and water, the hydraullc flu1d~ may al~o
16
~' .

~4;~3~
contaln other materlal~ ~uch as emul~iriers, eorro~ion
lnhlbltors, deroamer31 couplin6 agents, and the llke.
Suitable emul~lflers lnclude tho~e havin8 a
Hydrophlle-Lipophile ~alance (HLB) ln the range Or 3 to
20 (see Chapter 1 of the H~B Sy~tem publiqhed by ICI
United State~, Inc. (1976)). Example3 Or such
emul~lrierq are ethoxylated alkyl phenol~ or alkyl
amineq ln which the alkyl group~ contain from 14 to 24
carbon atom~, and She number o~ ethoxy groups varleq
from 3 to 10. Lon6 chaln, e.g. Cg-C1g alcohols can
alqo be u~ed a~ co-emulqirlers. The hydraulic rluid
may contaln up to 1.5~ of such an emulsifier, preferred
amounts Or emulslrler belng ~rom about 0.45 to 1.2~.
Small amounts, e.g. up to 0.5S, of varlouq
slllcone defoamer~ may be present ln the hydraullo
rluld, as well a3 small amounts, e.B. up to 0.1~ of
varlous corroslon lnhibitor~, 3uch as benzotr$azole and
tolutriazole. As a vapor phase corroqion lnhibitor
there may be u~ed varlouq water qoluble alkyl
alkanolamine~ Or the type used to react with ~uccinic
anhydride to form the dl~per~in~ agents, described
above. Freezlng polnt depreq~antq quch as ethylene
glycol, ir not pre~nt as the lubricant modirier, may
be lncluded in the hydraulic ~lulds in amounts
sufficient to lower the rreezing point So prevent
freezing Or the rluids at tho~e temperature~
; encountered $n uAe.
In order to llmit shlpplng and storage co~t~,
in ~sy be de31rabl¢ to rlrst prepare a water-dllutable
concentrate fro~ which the hydraullc ~luld may be

3~
prepared merely by addition of an appropriate amount of
water. Such a concentrate may have the composition
given in TABLE I, below.
TABLE I
Constituent GenerallyPreferred
Lubricant modifiers 5 ~4010 - 20
Thickener 5 - 2012 - 18
Dispersant 5 - 2010 - 15
EP additive 1 - 10 2 - 6
10 Water BalanceBalance
In preparing a hydraulic fluid of this
invention, the oil soluble lubricant modifier, if
present, dispersing agent and EP additive may be mixed
together and heated at a temperature of from about 130
to 150F. (54.Ll-65.6C.) for 30-45 minutes. Various
of the optional additives such as the corrosion
inhibitors, defoamers, emulsifiers, etc. may be added
to the water-miscible lubricant modifier, when present,
which is heated to about 150-160F. (65.5-71.1C.).
Otherwise such optional additives may be added directly
to the mixture containing the oil soluble lubricant
modifier and EP additive. The two mixtures can then be
combined in the absence of heat, water added, and the
mixture blended for 45-60 minutes to form a translucent
fluid containing about 35 - 45~ water. This mixture
can then be combined with an appropriate amount of
thickener and water to provide a hydraulic fluid of the
desired water content, usually 80% or more, and
viscosity.
In order that the invention may be better
18

3~
understood, several examples thereof will now be
described, purely by way o~ illustration, without
suggestion that the scope of the invention is limited
to the details thereof.
Example I
A hydraulic fluid of the present invention
having the composition set forth in TABLE II was
prepared by the method hereinbelow described:
19

~g~
TABLE_II
Component Weight Percenc
(a) Reaction product of polyisobutenyl
succinic anhydride (ave. MW 1000)
and diethylethanolamine 1.17
(b) Amidel 0.9
(c) EP additive2 0.38
(d) Polyglycol3 0.5
(e~ Thickener4 12.5
(f) Diethylethanolamine 0.5
(g) Additives5 0.06
(h) Water Balance
23.3 parts by weight of component (a), 18.0
parts of component (b), and 7.5 parts of component (c),
were mixed and heated to 130-150F. (54.4-65.6C.)
for 30-45 minutes. 1.2 parts of the additives,
component (g), were dissolved in 10.0 parts of
component (d) which has been heated to 150 - 160F
(660 _ 71C)o The two mixtures were combined; the heat
20 was shut off, and water was added in an amount such
Phosphate-modified condensation product obtained by
reacting about 1.5 mols of diethanolamine with about
1 mol of a mixture of stearic and oleic acids in the
presence of about 0.03 mols OI phosphoric acid.
2 Zinc dialkyl (C4-Clo) dithiophosphate.
3 Monobutyl ether of poly(oxyethylene-oxy-1,2-propylene)
glycol (MW 1500 - 4000).
4 Poly(oxyethylene (75~)-oxy-1,2-propylene)~lycol
(MW 25,000 - 30,000).
30 5 Benzotriazole and silicone defoamer.

3~
that the water comprised 40~ by weight of the final
mixture. The resulting batch was blended for 45-60
minutes to obtain a uniformly translucent liquid.
5 parts by weight of the translucent liquid,
prepared as above, were combined with 12.5 parts of
diethyl ethanolamine, component (f), in sufficient
water so that the total of all materials was 100~. The
resulting hydraulic fluid has an initial viscosity of
75-80 SUS at 100F. (37.8C.).
EXAMPLE II
The hydraulic fluid of Example I was
subjected to the following pump test:
TABLE III
Test Conditions
Pump Vickers V-104-C-10 Vane Pump
Pressure, psi 800
Speed, rpm 1200
Output (theoretical) gpm 7.5
Sump temperature F 115 -120 (46-49C. )
20 Filter size, microns 10
Test Results
Test #1 Test #2
Ring Wear Loss, mgs. 1678 244
Vanes Wear Loss, mgs. 5 3
Total Wear Loss 1683247
Wear Rate, mgs/hr. 12.2 5. 5
Viscosity Loss, % 2.3 5.6
Duration, hrs. 13845

~2~
Example III
A hydraulic fluid of the present invention
having the composition set forth in TABLE IV was
prepared by the method hereinbelow described:
TABLE IV
Component Weight Percent
(a) Reaction product of polyisobutenyl
succinic anhydride (ave. MW 1000)
and diethylethanolamine 1.17
10 (b) Amide1 0.9
(c) EP additive2 0.38
(d) Polyglycol3 0.5
(e) Thickener4 4.8
(f) Diethylethanolamine 0.5
(g) Additives5 0.06
(h) Water Balance
23.3 parts by weight of component (a), 18~0
parts of component (b), and 7.5 parts of compcnent (c),
were mixed and heated to 130-150F (54.40-65.60C.)
1 Phosphate-modified condensation product obtained by
reacting about 1.5 mols of diethanolamine with about
1 mol of a mixture of stearic and oleic acids in the
presence of about 0.03 mols of phosphoric acid.
2 Zinc dialkyl (C4-Clo) dithiophosphate.
3 Monobutyl ether of poly(oxyethylene-oxy-1,2-propylene)
glycol (MW 1500 - 4000).
4 Poly(oxyethylene (75%)-oxy-1,2-propylene)glycol (MW
12,000 15,000) capped with CH3(CH2)13CH~CH2 (M~ ~ 240).
5 Benzotriazole and silicone defoamer.
22

~Z~2~3~ ~
for 30-45 minutes. 1.2 parts of the additives,
component (g), were dissolved in 10.0 parts of
component (d) which has been heated to 150-160F
(65.6-71.1C.). The two mixtures were combined; the
heat was shut off, and water was added in an amount
such that the water comprised 40% by weight of the
final mixture. The resulting batch was blended for
45-60 minutes to obtain a uniformly translucent liquid.
5 parts by weight of the translucent liquid,
prepared as above, were combined with 4.8 parts of the
thickener, component (e), and 0.5 parts of diethyl-
ethanolamine, component (f), in sufficient water so
that the total of all materials was 100%. The
resulting hydraulic fluid had an initial viscosity of
190-200 SUS at 100F. (37.80C.).
_A~PLE IV
The hydraulic fluid of Example III was
subjected to the following pump test:
TABLE V
Test Conditions
Pump Vickers V-104-C-10 ~ane Pump
Pressure, ps~ 1000
Speed, rpm 1200
Output (theoretical) gpm 7.5
Sump temperature ~F 120 (490C)
Filter size, microns 10
:

~4æ~3~
Test Results
Test #1 Test #2
Ring Wear Loss, mgs. 1871 885
Vanes Wear Loss, mgs. 35 15
Total Wear Loss 1906 900
Wear Rate, mgs/hr.20.7 20.0
Viscosity Loss, %6.2 2.6
Duration, hrs. 92 45
Example V
- 10 A hydraulic fluid of the present invention
having the composition set forth in TABLE VI was
prepared by the method hereinbelow described:
TABLE VI
Component Weight Percent
(a) Dispersant1 1.06
(b) Hydrocarbon oil2 0.80
(c) EP additive3 0.34
(d) Polyglycol4 5.0
(e) Thickener5 5.0
20 (f) Additives6 o.o3
(g) Diethylethanolamine 0.38
(h) Fatty alcohol 0.23
(i) Water Balance
1 Reaction product of poly isobutenyl succinic anhydric
(ave. MW lOOO) and ethoxylated (3-10) ethoxy groups)
fatty (C12-C24) amine.
2 Polybutene (visc.~J400 SUS at 100F.).
3 Zinc dialkyl (C2-C10) dithiophosphate.
4 Monobutyl ether of poly(oxyethylene-oxy-1,2-propylene)
glycol (MW 1500 - 4000).
5 Poly(oxyethylene (75~)-oxy-1,2-propylene)glycol
(MW 25,000 - 30,000) capped with CH3(CH2)13CH~CH2
6 Benzotriazole and silicone defoamer.
24

~ 31
21.2 parts by weight of component (a) and
16.0 parts of component (b) were mixed and heated to
130-150F. (54.40-65.60C.) for 45-60 minutes. The
heat was shut off and 6.7 parts of component (c) and
7.5 parts of component (g) were added, and the mixture
; was blended for 30~45 minutes 0.9 parts of the
additive, component (f), were dissolved in 4.5 parts of
component (h) which had been heated to 150-160F.
(65.6-71.1C). The two mixtures were combined. Water
was added in an amount such that the water comprised
43.2~ by weight of the final mixture. The resulting
batch was blended for 115-60 minutes to obtain a
uniformly translucent liquid.
5 parts by weight of the translucent liquid,
prepared as above, were combined with 5 parts of the
thickener, component (e), and 5 parts of the
polyglycol, component td), in sufficient water so that
the total of all materials was 100~. The res~llting
hydraulic fluid has an initial viscosity of 150-250 SUS
20 at 100F. (37.80C).
Example VI
The hydraulic fluid of Example V was
subjectad to the following pump test using the same
type of test pump and the same test conditions as in
Example IV, TABLE V.
: 25

3Læ~3~
TABLE VII
Test Results
Test #1 Test #2 Test #3 Test #4
Duration; hrs. 307 452 336 300
Ring Wear Loss, mgs 620 1184 424 997
Vanes Wear Loss, mgs 30 33 25 11
Total Wear Loss 6501217 449 1008
Viscosity Change, ~+21.0 -12~2 nil ~5.3
Example VII
A hydraulic fluid of the present invention
having the composition set forth in TABLE VIII was
prepared by the method hereinbelow described:
TABLE VIII
Co=ponent Weight Percent
(a) Reaction product of polyisobutenyl
succinic anhydride (ave. M~ 1000)
and diethylethanolamine 1.25
(b) Amidel 1.0
(c) EP additive2 0.5
20 (d) Polyglycol3 2.19
(e) Thickener4 12.0
(f) Diethylethanolamine 0.5
(g) Additives5 0.06
(h) Water Balance
- _ _
1 Phosphate-modified condensakion product obtained by
reacting about 1.5 mols of diethanolamine with about
1 mol of a mixture of stearic and oleic acids in the
presence of about 0.03 mols of phosphoric acid.
2 Zinc dialkyl (C4-C1o) dithiophosphate.
3 Monobutyl ether of poly(oxyethylene-oxy-1,2-propylene)
glycol (MW 1500 _ 4000)
4 Poly(oxyethylene (75~)-o~y-1,2-propylene)glycol
(MW 25,000 - 30 J 000 ) .
5 Benzotriazole and silicone defoamer.
26

3~1L
12.5 parts by weight of component (a), 10.0
parts of component (b), and 5~ 0 parts of component (c),
were mixed and heated to 130-150F. (54. 40-65.60C. )
for 30-45 minutes. 0.6 parts of the additives,
component (g), were dissolved in 21.9 parts of
component (d) which has been heated to 150-160F
( 65 .60 71 .1C.). The two mixtures were combined; the
heat was shut off, and water was added in an amount
such that the water comprised 50~ by weight of the
final mixture. The resulting batch was blended for
45-60 minutes to obtain a uniformly translucent liqu$d.
lO.0 parts by weight of the translucent
liquid, prepared as above, were combined with 12.0
parts of the thickener, component (e), and 0.5 parts of
diethyl-ethanolamine, component (f), in sufficient
water so that the total of all materials was lO0~. The
resulting hydraulic fluid had an initial viscosity of
70 75 SUS at 100F. ( 37. 80C) .
EXAMPLE VIII
The hydraulic fluid of Example VII was
subjected to the following pump test:
TABLE IX
Test Conditions
Pump Vickers V-104-C-lO Vane Pump
~` Pressure, psi 1000
Speed, rpm 1200
Output (theoretical) gpm 7 . 5
Sump temperature F 125 - 140 (51.6-60C. )
Filter size, microns lO
. 27

~2~3~
Test Results
Test #1 Test #2
Ring Wear Loss, mgs. 85 113
Vanes Wear Loss, mgs. 9
Total Wear Loss 94 114
Wear Rate, mgs/hr. 0. 36 0 . g5
Viscosity Loss, % 1.4 3. 8
Duration, hrsO 264 120
EXAMPLE IX
The hydraulic fluid of Example V was
subjected to the following pump test:
TABLE X
Test Conditions
Pump Vickers F6-35V25 Vane Pump
Pressure, psi 1000
Speed, rpm 1200
Output (theoretical) gpm 25
Sump temperature F120 ( 49C. )
Filter size, microns 25
Test Results
Test #1 Test #2
Ring Wear Loss, mgs. 300 100
Vanes Wear Loss, mgs. 4 6
Total Wear Loss304 106
Wear Rate, mgs/hr. 0. 99 0 . 34
Viscosity Loss, ~3.5 14.8
Duration, hrs. 308 308
28

2~e3~
Example X
A hydraulic fluid of the present invention
having the composition set forth on Table XI was
prepared by the method herein below described:
TABLE XI
Components Weight Percent
(a) Dispersant1 2.50
(b) Hydrocarbon oil2 1~50
(c) Diethylethanolamine .72
10 (d) EP additive3 . 65
(e) Fatty alcohol .42
(f) Additives4 . 23
(g) Ethylene glycol 2~50
(h) Thickeners5 3~00
(i) Water Balance
38~5 parts of component (a) and 14.0 parts of
component (b~ were mixed and heated to 130-150F
(540-660C) for 45-60 minutes. The heat was shut o~f
and 11.0 parts of component (c) and lOoO parts of
component (d) were added, and the mixture was blended
for 30~45 minutes. 0.3 parts of benzotriazole were
1 Reaction product of polyisobutenyl succinic anhydride
: (Ave. MW 1000) and ethoxylated (3-10 ethoxy groups)
fatty (C12-C24) amine
2 Naphthenic mineral oil (visc ~ 100 SUS at 100F)
3 Zinc dialkyl (4-C10) dithiophosphate
4 Benzotriozole and silicone defoamer
~ 5 Poly (oxyethylene -75%-oxy-1,2-propylene)glycol
: 30 (MW 12,000-15,000) capped with CH3(CH2)13 CH~CH2
29

a3~
dissolved in 6.5 parts of component (e) which had been
heated to 150-160F (66-71C). The two mixtures were
combined. 10.7 parts of water were added, and the
mixture was blended for 45-60 minutes to obtain a
uniformly transparent liquid.
6.5 parts by weight of the transparent
liquid, prepared as above were combined with 87.8 parts
of water, 2.5 parts of ethylene glycol, 3.0 parts of
component (i) and o.2 parts of silicone defoamer. This
mixture was belended for 45-60 minutes until a uniforrn
translucent product was obtained. The resulting
hydraulic ~luid had an initial viscosity of 210-320
SUS .
EXAMPLE XI
The hydraulic fluid of Example X was
subjected to pump tests using the same type o~ pump and
the same conditions as in Example IV, Table V, except
for duration of the tests. The results of these tests
are set forth in Table XII, below.
Table XII
; Text Results
Test No. 1 2 3 4 5
Duration, hrs. 1146 1008 616 232 881
Ring ~ear Loss, mgs 54 181 12 11 13
Vanes Wear Loss, mgs 33 20 19 7 25
Total Wear Loss, mgs 87 201 31 18 38
Wear Rate, mgs/hr 0.08 0.20 0.050.08 0.04
Viscosity:
Initial, SUS @100F 320 260 250 246 233
Final, SUS ~100F 205 175 366 344 176

~:429L3~
EXAMPLE XII
The hydraulic fluid of Example X was
subjected to the following pump tests, and the test
conditions used and results obtained are set forth in
Table XIII, below:
TABLE XIII
TEST CONDITIONS
Pump Vickers 25 V17 A Intravane Pump
Pressure, psi 1000
10 Speed, rpm 1200
Output (theoritical) gpm 17
Sump temperature, F115-120
Filter size, microns 25
Test Results
Test No. 1 2 3
Duration, hrs. 1172 4761148
Ring Wear Loss, mgs Nil 5 170
Vanes Wear Loss, mgs 6 5 17
Intravane Wear Loss, mgs 2 3 5
20 Total Wear Loss, mgs 8 13 l9L,
Wear Rate, mgs/hr 0.007 0.0270.17
Viscosity:
Initial, SUS 303 225 230
Final, SUS 252 245 247
Note: (1) Tests 1 and 2 were run with negative head
condition using the Vickers 282 series vane pump.
(2) Test 3 was run with 12 inch supercharge
inlet condition using Vickers 180 series vane pump.
EXAMPLE XIII
The hydraulic fluid of Example X was

:~L24!24;~
subjected to pump tests using the same type of pump and
the same conditions as in Example IX, Table X except
for duration of the tests, and the results obtained are
set forth in Table XIV, below:
TABLE XIV
TEST RESULTS
Test No. 1 2
Duration, hrs. 1080 706
Ring Wear loss, mgs 50 100
10 Vanes Wear Loss, mgs 8 5
Total Wear Loss, mgs 58 105
Wear Rate, mgs/hr0.054 0.15
Viscosity
Initial, SUS ~ 100F 310 240
Final, SUS @ 100F 183 267
32