t FP12-0011-00
DESCRIPTION
Title of Invention
GREASE COMPOSITION
Technical Field
5 [0001] The present invention relates to a lubricating oil and a grease
composition, and particularly relates to a grease composition having
favorable antiwear performance in a friction part of a non-ferrous metal.
Background Art
[0002] Non-ferrous metals such as aluminum and alloys thereof
10 (hereinafter, also referred to as the aluminum material) are light metals
which are strong and are good in thermal conductivity, and are generally
used in the fields of transport and structure in which weight savings are
important.
[0003] Conventionally, as grease compositions for use in lubrication of
15 a sliding part having a non-ferrous metal, generally used grease
compositions have been used in many cases. However, in this case,
the fact is that sufficient sliding properties are not achieved.
[0004] Then, as a means for improving lubricating properties to
non-ferrous metals, use of additives such as higher alcohols, fatty acid
20 esters, fatty acids, alkylene glycol-esterified products, and a-olefins has
been proposed. It is considered that, among these additives,
particularly higher alcohols, secondly fatty acid esters are high in the
effect of improving lubricating properties (see Patent Literature 1).
Citation List
25 Patent Literature
[0005] [Patent Literature 1] Japanese Unexamined Patent Application
t FP12-0011-00
Publication No. 8-53685
Summary of Invention
Technical Problem
[0006] However, even in the case of the grease composition using the
5 additives, there is no effect in the case where sliding is performed under
extreme pressure conditions where a sliding part having a non-ferrous
metal is subjected to a high load, resulting in galling (seizure) to allow
wear to rapidly progress.
[0007] In addition, additives such as an organic molybdenum
10 compound such as tricresyl phosphate (TCP) or molybdenum
dithiocarbamate (MoDTC) exhibit the effect of preventing seizure under
extreme pressure conditions during sliding between iron materials, but
such an effect is due to the chemical reaction of iron and the additives.
Therefore, even if these additives are used, the surface modification by
15 the chemical reaction is not made to a non-ferrous metal, and the effect
of preventing galling is not observed.
[0008] The present invention has made under such circumstances, and
an object thereof is to provide a grease composition that enables galling
(seizure) and wear to be sufficiently suppressed and that enables sliding
20 properties to be achieved at a high level even in the case where sliding
is performed under extreme pressure conditions where a sliding part
having a non-ferrous metal is subjected to a high load.
Solution to Problem
[0009] In order to solve the above problem, the present invention
25 provides a grease composition containing at least one lubricating base
oil selected from a mineral oil and a synthetic oil, and 1 to 40% by mass
FP12-0011-00
of a thickener and 0.5 to 15% by mass of an alkenyl succinimide based
on the total amount of the grease composition, for use in a lubricating
part in which at least one of members is made of a non-ferrous metal.
[0010] The alkenyl succinimide in the present invention is preferably at
5 least one selected from an alkenyl succinimide not containing boron and
a boron-containing alkenyl succinimide whose boron content is more
than 0 % by mass and 1.0% by mass or less based on the total amount of
the boron-containing alkenyl succinimide.
[0011] In addition, the alkenyl succinimide preferably has a
10 polybutenyl group whose weight average molecular weight is 2000 or
less.
[0012] In addition, the non-ferrous metal is preferably at least one
selected from aluminum, magnesium, copper, titanium, nickel,
chromium, zinc, tin, lead and titanium, and alloys of two or more
15 thereof, and it is more preferable that the non-ferrous metal be at least
one selected from aluminum, magnesium, copper and titanium, and
alloys thereof
[0013] In addition, the Vickers hardness of the non-ferrous metal is
preferably 150 or less. Other aspect of the present invention provides
20 a lubricating method of bringing the above-described grease
composition into contact with a lubricating part in which at least one of
members is made of a non-ferrous metal.
Advantageous Effects of Invention
[0014] According to the present invention, a grease composition that
25 enables galling (seizure) and wear to be sufficiently suppressed and that
enables sliding properties to be achieved at a high level even in the case
FP12-0011-00
where sliding is performed under extreme pressure conditions where a
sliding part having a non-ferrous metal is subjected to a high load.
Description of Embodiments
[0015] Hereinafter, a suitable embodiment of the present invention will
5 be described in detail.
[0016] A grease composition according to the present embodiment
contains at least one lubricating base oil selected from a mineral oil and
a synthetic oil, and 1 to 40% by mass of a thickener and 0.5 to 15% by
mass of an alkenyl succinimide based on the total amount of the grease
10 composition.
[0017] Examples of the lubricating base oil include a mineral oil and/or
a synthetic oil. Examples of the mineral oil include those which are
obtained by a procedure usually carried out in a lubricating oil
production process of the petroleum refining industry, for example, by
15 refining a lubricating oil fraction obtained from normal-pressure
distillation and reduced-pressure distillation of crude oil by carrying out
one or more of treatments such as solvent deasphalting, solvent
extraction, hydrocracking, solvent dewaxing, catalytic dewaxing,
hydrogenation refining, sulfuric acid washing, and a clay freatment.
20 [0018] In addition, examples of the synthetic oil include poly-a-olefins
such as polybutene, a 1-octene oligomer, and a 1-decene oligomer, or
hydrogenated products thereof, ethylene-a-olefin copolymers; diesters
such as difridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate,
ditridecyl adipate, and di-3-ethylhexyl sebacate; polyol esters such as
25 trimethylolpropane caprylate, trimethylolpropane pelargonate,
pentaerythritol-2-ethyl hexanoate, and pentaerythritol pelargonate;
c FP12-0011-00
alkylnaphthalenes; alkylbenzenes, polyoxyalkylene glycols; polyphenyl
ethers; dialkyl diphenyl ethers; silicone oil; or mixtures thereof
[0019] As the thickener, every thickener including soaps such as a
metal soap and a composite metal soap,; and non-soaps such as bentone,
5 silica gel, a urea compound, a urethane»urea compound, and a urethane
compound can be used. Among the non-soap thickeners, a urea-based
thickener made of a urea compound or a urethane»urea compound is
preferable because it has no metal within the structure thereof to be
excellent in oxidative stability, and is high in dropping point to be kept
10 in the form of gel even at a high temperature.
[0020] The content of the thickener is 1 to 40% by mass and preferably
3 to 30% by mass based on the total amount of the grease composition.
In the case where the content of the thickener is less than Wo by mass,
the effect as the thickener is low and thus is not sufficient in the form of
15 grease, and in the case where it is more than 40%) by mass, the obtained
grease is too hard as grease to exert sufficient lubricating performance.
[0021] Examples of the alkenyl succinimide include an alkenyl
succinimide compound having at least one straight or branched alkyl
group or alkenyl group whose carbon number is 40 to 400, preferably
20 60 to 350, in the molecule. In the case where the carbon number of the
alkyl group or alkenyl group is less than 40, the solubility of the
compound in the lubricating base oil may be decreased, and on the other
hand, in the case where the carbon number of the alkyl group or alkenyl
group is more than 400, the low temperature fluidity of a lubricating oil
25 composition may be deteriorated. The alkyl group or alkenyl group
may be straight or branched, and preferred specific examples thereof
c FP12-0011-00
include a branched alkyl group or a branched alkenyl group derived
from oligomers of olefins such as propylene, 1-butene and isobutylene,
and an ethylene-propylene co-oligomer.
[0022] More specific examples of the alkenyl succinimide in the
5 present embodiment include a mono-type alkenyl succinimide
represented by the following formula (1), in which succinic anhydride is
added to one end of a polyamine in imidation, and/or a bis-type alkenyl
succinimide represented by the following formula (2), in which succinic
anhydride is added to both ends of a polyamine in imidation.
10 [Chemical Formula 1]
R^—e—c
N-(CH2CH2NH)rH (1)
HjC—C
O
[Chemical Formula 2]
I N-(CH2CH2NH)t,-CH2CH2-N | (2)
[0023] In the above formula (1) and formula (2), R \ R^ and R^ each
15 independently represent a straight or branched alkyl group or alkenyl
group whose carbon number is 40 to 400, preferably whose carbon
number is 60 to 350. a represents an integer of 1 to 10, preferably an
integer of 2 to 5, and b represents an integer of 1 to 10, preferably an
integer of 2 to 5.
20 [0024] In the present invention, any of the mono-type and bis-type
^ (» FP12-0011-00
succinimides can be used, and the number average molecular weight of
the entire component contained is preferably 500 to 10000, more
preferably 1000 to 5000, and further preferably 2000 to 4000. The
weight average molecular weight of the succinimide is 1000 to 20000,
5 more preferably 2000 to 10000, and further preferably 3000 to 5000.
If the number average molecular weight is less than the lower limit, the
solubility in the lubricating base oil may be decreased, and if it is more
than the upper limit, the low temperature fluidity of a lubricating oil
composition may be deteriorated. In addition, in the cases where the
10 number average molecular weight is less than the lower limit and where
it is more than the upper limit, sufficient antiwear properties are not
achieved during sliding. The molecular weight of the succinimide in
the present invention was measured by GPC (gel permeation
chromatography).
15 In the alkenyl succinimides represented by the above formulae
(1) and (2), the weight average molecular weights of the groups
represented by R \ R^ and R^ are preferably 200 to 5000, more
preferably 500 to 2000, and further preferably 700 to 1500.
[0025] In addition, the nitrogen content of the alkenyl succinimide is
20 preferably 0.5 to 5% by mass, and more preferably 1 to 3% by mass.
[0026] The method for producing the alkenyl succinimide is not
particularly limited, and for example, the alkenyl succinimide is
obtained by reacting a compound having an alkyl group or alkenyl
group whose carbon number is 40 to 400 with maleic anhydride at 100
25 to 200°C to obtain an alkyl succinic acid or alkenyl succinic acid, and
reacting the alkyl succinic acid or alkenyl succinic acid with a
L FP12-0011-00
poly amine.
[0027] Examples of the polyamine include diethylenetriamine,
triethylenetetramine, tetraethylenepentamine, and
pentaethylenehexamine.
5 [0028] The boron-containing alkenyl succinimide can be obtained by
allowing a boron compound such as boric acid, borate or boric acid
ester to act on the alkenyl succinimides represented by the above
formula (1) and formula (2). Examples of the boric acid include
orthoboric acid, metaboric acid, or tetraboric acid.
10 [0029] As the succinimide compound in the present embodiment, any
of one containing boron and one not containing boron can be used, but
the alkenyl succinimide not containing boron is preferable from the
viewpoint of seizure resistance, and the boron content in the case of
blending the boron-containing alkenyl succinimide is more than 0% by
15 mass and 1.0% by mass or less, preferably more than 0% by mass and
0.5% by mass or less, and more preferably more than 0% by mass and
0.025% by mass or less, based on the total amount of the
boron-containing alkenyl succinimide. If the boron content is more
than 1.0% by mass, the seizure resistance of the aluminum material may
20 be insufficient.
[0030] The content of the alkenyl succinimide is 0.5 to 15% by mass
and preferably 1.5 to 10% by mass based on the total amount of the
grease composition. If the content of the alkenyl succinimide is less
than 0.5% by mass, the effect of adding the alkenyl succinimide is not
25 sufficiently exerted, and on the other hand, if it is more than 10% by
mass, the effect matching the content of the alkenyl succinimide is not
1HH
FP12-0011-00
achieved in terms of the seizure resistance of the aluminum material,
resulting in an economic disadvantage.
[0031] The grease composition according to the present embodiment
can, if necessary, contain additives such as a solid lubricating agent, an
5 extreme pressure agent, an antioxidizing agent, an oily agent, a
rust-preventive agent, and a viscosity index improver in order to further
enhance performance, as long as properties thereof are not impaired.
[0032] Specific examples of the solid lubricating agent include
graphite, carbon black, boron nitride, graphite fluoride,
10 polytetrafluoroethylene, molybdenum disulfide, antimony sulfide, and
alkali (earth) metal borates.
[0033] Specific examples of the antioxidizing agent include
phenol-based compounds such as 2,6-di-t-butylphenol and
2,6-di-t-butyl-p-cresol; amine-based compounds such as dialkyl
15 diphenylamine, phenyl-a-naphthylamine, and
p-alkylphenyl-a-naphthylamine; sulfur-based compounds; and
phenothiazine-based compounds.
[0034] Specific examples of the extreme pressure agent include sulfide
fats and oils, sulfide esters, sulfides, organic molybdenum compounds,
20 phosphoric acid esters, phosphorous acid esters, acidic phosphoric acid
esters, thiophosphates, and thiophosphites.
[0035] Specific examples of the oily agent include amines such as
laurylamine, myristylamine, palmitylamine, stearylamine, and
oleylamine; higher alcohols such as lauryl alcohol, myristyl alcohol,
25 palmityl alcohol, stearyl alcohol, and oleyl alcohol; higher fatty acids
such as lauric acid, myristic acid, palmitic acid, stearic acid, and oleic
^dl FP12-0011-00
acid; fatty acid esters such as methyl laurate, methyl myristate, methyl
palmitate, methyl stearate, methyl oleate, glycerol monooleate, and
glycerol monostearate; amides such as laurylamide, myristylamide,
palmitylamide, stearylamide, and oleylamide; and fats and oils.
5 [0036] Specific examples of the rust-preventive agent include metal
soaps; polyhydric alcohol partial esters such as sorbitan fatty acid ester;
amines; phosphoric acid; and phosphates.
Specific examples of the viscosity index improver include
polymethacrylate, polyisobutylene, and polystyrene.
10 [0037] The dropping point of the grease composition according to the
present embodiment is preferably 80°C or higher and more preferably
150°C or higher. If the dropping point is lower than the lower limit,
the grease composition cannot be kept in the form of gel in use at a
constant temperature, resulting in lubrication failure and contamination
15 of surrounding in some cases.
[0038] The grease composition according to the present embodiment
can be suitably used for lubricating a lubricating part in which at least
one of members has aluminum or a non-ferrous metal. Therefore, the
grease composition according to the present embodiment is very useful
20 as grease for non-ferrous metals in the fields of transport and structure
in which weight savings are important. Herein, the reason why the
grease composition according to the present embodiment has the
excellent effects as described above is because the alkenyl succinimide
compound strongly adsorbs to the non-ferrous metal to form a robust oil
25 film, thereby leading to significant enhancement in lubricating
properties.
10
c rpi2-ooii-oo
[0039] As the non-ferrous metal, at least one selected from aluminum,
magnesium, copper, titanium, nickel, chromium zinc, tin, lead and
titanium, and alloys thereof can be used. It is more preferable that the
non-ferrous metal be, among them, at least one selected from aluminum,
5 magnesium, copper and titanium, and alloys thereof Herein, it is
preferable that these alloys be made of metal such as aluminum as a
main component, and it is preferable that the content of metals other
than the main component be less than 10% by mass and further less than
2% by mass.
10 [0040] In addition, it is preferable that the Vickers hardness of the
non-ferrous metal be 150 or less, and it is more preferable that it be 100
or less.
Examples
[0041] Hereinafter, the present invention will be more specifically
15 described based on Examples and Comparative Examples, but the
present invention is not limited to the following Examples at all.
[0042] [Examples 1 to 11, Comparative Examples 1 to 6]
In Examples 1 to 11 and Comparative Examples 1 to 6, each of
lubricating base oils and each of additives shown below were used to
20 prepare a grease composition having composition shown in Tables 1 to
3. Herein, the nitrogen content and the boron content of each of CI to
C4 mean the contents of nitrogen and boron based on the total amount
of the boron-containing alkenyl succinimide.

25 Al: poly-a-olefin (kinetic viscosity at 40°C: 47 mm /s)
A2: mineral oil (highly refined oil, kinetic viscosity at 40°C: 95 mm^/s)
11
\ :
FP12-0011-00
A3: polyol ester oil (kinetic viscosity at 40°C: 30 mm /s)

B1: urea-based thickener
B2: Ca soap
5 B3: Li soap
B4: Li soap-mixed soap

CI: alkenyl succinimide (weight average molecular weight of
polybutenyl group: 1000, nitrogen content: 1.3%, boron content: 0%,
10 number average molecular weight of entire compound: 3030, weight
average molecular weight of entire compound: 4490)
C2: boron-containing alkenyl succinimide (weight average molecular
weight of polybutenyl group: 1300, nitrogen content: 1.6%), boron
content: 0.44%, number average molecular weight of entire compound:
15 3070, weight average molecular weight of entire compound: 4430)
C3: boron-containing alkenyl succinimide (weight average molecular
weight of polybutenyl group: 1000, nitrogen content: 2.3%, boron
content: 1.9%), number average molecular weight of entire compound:
3010, weight average molecular weight of entire compound: 4180)
20 C4: boron-containing alkenyl succinimide (weight average molecular
weight of polybutenyl group: 2300, nitrogen content: 0.88%), boron
content: 0.23%, number average molecular weight of entire compound:
4940, weight average molecular weight of entire compound: 8040)

25 Dl: lauryl alcohol
D2: glycerol monooleate
12
•lllpl
FP12-0011-00
D3: TCP (tricresyl phosphate)
D4: MoDTC (molybdenum dithiocarbamate)
[0043] The specific method of adjusting each of the grease
compositions of Examples 1 to 11 and Comparative Examples 1 to 6 is
5 as follows.
First, in Examples 1 to 6, 10 and 11, and Comparative Example
2, diphenylmethane-4,4'-diisocyanate was dissolved in any of
lubricating base oils Al to A3 with heating, and a product prepared by
dissolving cyclohexylamine in any of lubricating base oils Al to A3
10 with heating was added thereto. Any of alkenyl succinimides CI to C4
was added to the produced gel-like substance, stirred and then passed
through a roll mill to obtain a urea-based grease composition.
In addition, in Examples 7 to 9, a thickener B2, B3 or B4 and an
alkenyl succinimide CI were added to a lubricating base oil Al
15 (poly-a-olefin), stirred and then passed through a roll mill to obtain a
soap type grease composition.
In addition, in Comparative Example 1,
diphenylmethane-4,4'-diisocyanate was dissolved in a lubricating base
oil Al with heating, and a product prepared by dissolving
20 cyclohexylamine in any of lubricating base oils Al to A3 with heating
was added thereto. The produced gel-like substance was stirred, and
then passed through a roll mill to obtain a urea-based grease
composition.
In addition, in Comparative Examples 3 to 6,
25 diphenylmethane-4,4'-diisocyanate was dissolved in a lubricating base
oil Al with heating, and a product prepared by dissolving
13
FP12-0011-00
cyclohexylamine in a lubricating base oil Al with heating was added
thereto. Any of other additives Dl to D4 was added to the produced
gel-like substance, stirred and then passed through a roll mill to obtain a
urea-based grease composition. Herein, the dropping point of the
5 urea-based grease composition of the present Example was 250°C or
higher.
[0044] [SRV Oscillating Friction and Wear Test I]
Each of the grease compositions of Examples 1 to 11 and
Comparative Examples 1 to 6 was subjected to the SRV friction and
10 wear test under the following conditions to measure an SRV test seizure
load (N).

Test piece: 10 mmcj) steel ball (SUJ2)/aluminum alloy plate (ADC 12)
Oil temperature: 25°C
15 Stroke: 2 mm
Frequency: 30Hz
Time: 10 minutes
In accordance with ASTM D5706-97 (Standard Test Method for
Determining Extream Pressure Properties of Lubricating greases Using
20 A High-Frequency, Linera-Oscillation (SRV) Test Machine), a load at
the time when the friction coefficient exceeded 0.2 during the sliding
test for 10 minutes was determined as a seizure load (N).
The obtained results are shown in Tables 1 to 3.
14
s ^ FP12-0011-00
[0045] [Table 1]
Lubricating base
oil,
% by mass
Thickener,
% by mass
Alkenyl
succinimide,
% by mass
Other additives,
% by mass
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
D l ^
D2
D3
D4
SRV test seizure load, N
Example
1
Balance
-
-
17
-
-
-
10
-
-
-
-
-
-
-
350
Example
2
Balance
-
-
17
-
-
-
5
-
-
-
-
-
-
-
300
Example
3
Balance
-
-
17
-
-
-
0.5
-
-
-
-
-
-
-
250
Example
4
Balance
-
-
17
-
-
-
-
5
-
-
-
-
-
-
200
Example
5
-
Balance
-
17
-
-
-
5
-
-
-
-
-
-
-
300
Example
6
-
-
Balance
17
-
-
-
5
-
-
-
-
-
-
-
300
[0046] [Table 2]
Lubricating base
oil,
% by mass
Thickener,
% by mass
Alkenyl
succinimide,
% by mass
Other additives,
% by mass
SRV test seizure
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
Dl
D2
D3
D4
oad, N
Example
7
Balance
-
-
-
13
-
-
5
-
-
-
-
-
-
-
350
Example
8
Balance
-
-
-
-
10
-
5
-
-
-
-
-
-
-
250
Example
9
Balance
-
-
-
-
-
10
5
-
-
-
-
-
-
-
300
Example
10
Balance
-
-
17
-
-
-
-
-
5
-
-
-
-
-
200
Example
11
Balance
-
-
17
-
-
-
-
-
-
5
-
-
-
-
200
15
\ %J rpi2-ooii-oo
[0047] [Table 3]
10
Lubricating base
oil,
% by mass
Thickener,
% by mass
Alkenyl
succinimide,
% by mass
Other additives,
% by mass
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
Dl
D2
D3
D4
SRV test seizure load, N
Comparati
ve
Example
1
Balance
-
-
17
-
-
-
-
-
-
-
-
-
-
-
100
Comparati
ve
Example
2
Balance
-
-
17
-
-
-
0.2
-
-
-
-
-
-
-
100
Comparati
ve
Example
3
Balance
-
-
17
-
-
-
-
-
-
-
5
-
-
-
100
Comparati Comparati Comparati
ve ve ve
Example Example Example
4 5 6
Balance
-
-
17
-
-
-
-
-
-
-
-
5
-
-
100
Balance
-
-
17
-
-
-
-
-
-
-
-
-
5
-
100
Balance
-
-
13
-
-
-
-
-
-
-
-
-
5
100
[0048] It can be seen from the results shown in Tables 1 and 2 that the
grease compositions of Examples 1 to 11 are each a grease composition
whose seizure load in sliding of an iron-aluminum alloy is high to allow
the frictional wear of iron and an aluminum alloy to be lower.
On the contrary, it can be seen from the results shown in Table 3
that the grease compositions of Comparative Examples 1 and 2, to
which the alkenyl succinimide is not added, are insufficient in the effect
of reducing wear on sliding of an iron-aluminum alloy. Also, the
grease compositions of Comparative Examples 4 to 5 are insufficient in
the effect of reducing wear on sliding of an iron-aluminum alloy under a
high load, although they each contain lauryl alcohol or glycerol
monooleate having an effect on antiwear properties of a non-ferrous
metal.
16
v^ rpi2-ooii-oo
It can also be seen that the grease compositions of Comparative
Examples 6 to 7 are insufficient in the effect of reducing wear on sliding
of an iron-aluminum alloy as in the grease compositions of Comparative
Examples 1 and 2, although they each contain tricresyl phosphate (TCP)
5 or an organic molybdenum compound (MoDTC) having the effect of
preventing seizure between iron materials under extreme pressure.
The results support that, even if lauryl alcohol, glycerol
monooleate, TCP or MoDTC is used, the surface modification by the
chemical reaction is not made to the aluminum material, not achieving
10 the effect of preventing galling (seizure).
[0049] [Examples 12 to 17, Comparative Examples 7 to 9]
In Examples 12 to 17 and Comparative Examples 7 to 9, each of
the lubricating base oils Al to A3 and each of the additives Bl, CI, C2,
Dl and D3 were used to prepare a grease composition having
15 composition shown in Tables 4 and 5.
[0050] The specific method of adjusting each of the grease
compositions of Examples 12 to 17 and Comparative Examples 7 to 9 is
as follows.
First, in Examples 12 to 17, diphenylmethane-4,4'-diisocyanate
20 was dissolved in any of the lubricating base oils Al to A3 with heating,
and a product prepared by dissolving cyclohexylamine in any of the
lubricating base oils Al to A3 with heating was added thereto. Any of
the alkenyl succinimides CI and C2 was added to the produced gel-like
substance, stirred and then passed through a roll mill to obtain a
25 urea-based grease composition.
In addition, in Comparative Examples 7,
17
w rpi2-ooii-oo
diphenylmethane-4,4'-diisocyanate was dissolved in the lubricating base
oil Al with heating, and a product prepared by dissolving
cyclohexylamine in any of the lubricating base oils Al to A3 with
heating was added thereto. The produced gel-like substance was
5 stirred, and then passed through a roll mill to obtain a urea-based grease
composition.
In addition, in Comparative Examples 8 and 9,
diphenylmethane-4,4'-diisocyanate was dissolved in the lubricating base
oil Al with heating, and a product prepared by dissolving
10 cyclohexylamine in the lubricating base oil Al with heating was added
thereto. Any of other additives Dl to D4 was added to the produced
gel-like substance, stirred and then passed through a roll mill to obtain a
urea-based grease composition.
[0051] [SRV Oscillating Friction and Wear test II]
15 Each of the grease compositions of Examples 12 to 17 and
Comparative Examples 7 to 9 was subjected to the SRV friction and
wear test in the same manner as in the above SRV oscillating friction
and wear test I except that the aluminum alloy plate (ADC 12) of the test
piece was changed to a magnesium alloy plate (AZ31), to measure an
20 SRV test seizure load (N). The obtained results are shown in Tables 4
and 5.
18
k FP12-0011-00
[0052] [Table 4]
Lubricating base
oil,
% by mass
Thickener,
% by mass
AUcenyl
succinimide,
% by mass
Other additives,
% by mass
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
Dl
D2
D3
D4
SRV test seizure load, N
Example
12
-
Balance
-
17
-
-
-
10
-
-
-
-
-
-
-
400
Example
13
-
Balance
-
17
-
-
-
5
-
-
-
-
-
-
-
300
Example
14
-
Balance
-
17
-
-
-
0.5
-
-
-
-
-
-
-
200
Example
15
-
Balance
-
17
-
-
-
-
5
-
-
-
-
-
-
200
Example
16
Balance
-
-
17
-
-
-
5
-
-
-
-
-
-
-
300
Example
17
-
-
Balance
17
-
-
-
5
-
-
-
-
-
-
-
300
[0053] [Table 5]
Lubricating base
oil, %
by mass
Thickener,
% by mass
Alkenyl
succinimide,
% by mass
Other additives,
% by mass
SRV test seizure
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
Dl
D2
D3
D4
oad, N
Comparative
Example
7
Balance
-
-
17
-
-
-
-
-
-
-
-
-
-
-
100
Comparative
Example
8
Balance
-
-
17
-
-
-
-
-
-
-
5
-
-
-
100
Comparative
Example
9
Balance
-
-
17
-
-
-
-
-
-
-
-
-
5
-
100
[0054] It can be seen from the results shown in Table 4 that the grease
19
iti FP12-0011-00
compositions of Examples 12 to 17 are each a grease composition
whose seizure load in sliding of an iron-magnesium alloy is high to
allow the frictional wear of iron and a magnesium alloy to be lower.
On the contrary, it can be seen from the results shown in Table 5
5 that the grease composition of Comparative Example 7, to which the
alkenyl succinimide is not added, is insufficient in the effect of reducing
wear on sliding of an iron-magnesium alloy. It can also be seen that
the grease compositions of Comparative Examples 8 and 9 are
insufficient in the effect of reducing wear on sliding of an
10 iron-magnesium alloy as in the grease composition of Comparative
Example 7, although they each contain lauryl alcohol having the effect
of preventing wear on the non-ferrous metal or tricresyl phosphate
(TCP) having the effect of preventing seizure between iron materials
under extreme pressure. The results support that, even if lauryl alcohol
15 or TCP is used, the surface modification by the chemical reaction is not
made to the magnesium material such as magnesium and a magnesium
alloy, not achieving the effect of preventing galling (seizure).
[0055] [Example 18, Comparative Example 10]
In Example 18 and Comparative Example 10, the lubricating
20 base oil Al and each of the additives Bl and CI were used to prepare a
grease composition having each composition shown in Table 6.
[0056] The specific method of adjusting each of the grease
compositions of Example 18 and Comparative Example 10 is as
follows.
25 First, in Example 18, diphenylmethane-4,4'-diisocyanate was
dissolved in the lubricating base oil Al with heating, and a product
20
FP12-0011-00
prepared by dissolving cyclohexylamine in the lubricating base oil Al
with heating was added thereto. The alkenyl succinimide CI was
added to the produced gel-like substance, stirred and then passed
through a roll mill to obtain a urea-based grease composition.
5 In addition, in Comparative Example 10,
diphenylmethane-4,4'-diisocyanate was dissolved in the lubricating base
oil Al with heating, and a product prepared by dissolving
cyclohexylamine in the lubricating base oil Al with heating was added
thereto. The produced gel-like substance was stirred, and then passed
10 through a roll mill to obtain a urea-based grease composition.
[0057] [SRV Oscillating Friction and Wear test III]
Each of the grease compositions of Example 18 and
Comparative Example 10 was subjected to the SRV friction and wear
test in the same manner as in the above SRV oscillating fiiction and
15 wear test I except that the aluminum alloy plate (ADC 12) of the test
piece was changed to a copper alloy plate (C3604 material), to measure
an SRV test seizure load (N). The obtained results are shown in Table
6.
21
FP12-0011-00
[0058] [Table 6]
Lubricating base oil,
% by mass
Thickener,
% by mass
Alkenyl
succinimide,
% by mass
Other additives,
% by mass
Al
A2
A3
Bl
B2
B3
B4
CI
C2
C3
C4
Dl
D2
D3
D4
SRV test seizure load, N
Example
18
Balance
-
-
17
-
-
-
5
-
-
-
-
-
-
-
400
Comparative Example
10
Balance
-
-
17
-
-
-
-
-
-
-
-
-
-
-
100
[0059] It can be seen from the results shown in Table 6 that the grease
composition of Example 18 is a grease composition whose seizure load
in sliding of an iron-copper alloy is high to allow the frictional wear of
iron and a copper alloy to be lower.
On the contrary, it can be seen from the results shown in Table 6
that the grease composition of Comparative Example 10, to which the
alkenyl succinimide is not added, is insufficient in the effect of reducing
wear on sliding of an iron-copper alloy.
10
22

FP12-0011-00
CLAIMS
[Claim 1]
A grease composition containing:
at least one lubricating base oil selected from a mineral oil and a
5 synthetic oil, and
1 to 40% by mass of a thickener and 0.5 to 15% by mass of an alkenyl
succinimide based on the total amount of the grease composition,
the grease composition being used for a lubricating part in which at least
one of members is made of a non-ferrous metal.
10 [Claim 2]
The grease composition according to claim 1, wherein the
alkenyl succinimide is at least one selected from an alkenyl succinimide
not containing boron and a boron-containing alkenyl succinimide whose
boron content is more than 0 %> by mass and 1.0% by mass or less based
15 on the total amount of the boron-containing alkenyl succinimide.
[Claim 3]
The grease composition according to claim 1 or 2, wherein the
succinimide compound has a polybutenyl group whose weight average
molecular weight is 2000 or less.
20 [Claim 4]
The grease composition according to any one of claims 1 to 3,
wherein the non-ferrous metal is at least one selected from aluminum,
magnesium, copper, titanium, nickel, chromium, zinc, tin, lead and
titanium, and alloys thereof.
25 [Claim 5]
The grease composition according to any one of claims 1 to 4,
23
V FP12-0011-00
wherein a Vickers hardness of the non-ferrous metal is 150 or less.
[Claim 6]
A lubricating method of bringing the grease composition
according to any one of claims 1 to 3 into contact with a lubricating part
in which at least one of members is made of a non-ferrous metal.