DESCRIPTION
Title of Invention: LUBRICATING OIL COMPOSITION
Technical Field
[0001] The present invention relates to a lubricating oil composition.
5 Background Art
[0002] Lubricating oils are prepared by blending a base oil with
additives according to the required characteristics. For example,
Patent Literature I below discloses a lubricating oil obtained by
blending a base oil with an amine antioxidant and a phosphorus extreme
10 pressure agent as a lubricating oil capable of achieving heatloxidation
stability, sludge resistance, lubricating properties, a long life, and water
separability all at high levels.
Citation List
Patent Literature
15 [0003] Patent Literature 1: Japanese Unexamined Patent Publication
NO. 2005-239897
Summary of I~lvention
Technical Problem
[0004] Meanwhile, in view of the global environment, lubricating oils
20 having minimal environmental impact are desired. Many additives
used for lubricating oils contain metal elements such as transition
metals, a phosphorus element, a sulfur element, and a nikogen element.
' [0005] On the other hand, effective amounts of additives generally need
to be blended with a base oil in order to obtain the desired effects of
25 adding such additives.
[0006] The present invention has been made in view of the above
problem, and an object of the present invention is to provide a
lubricating oil composition in which the metal elenlent, phospho~us
element, sulfur element, and nitrogen element contents are small, the
environmental impact of which can be reduced, and from which the
5 effects of adding additives can be effectively obtained.
Solution to Problem
[0007] The present invention provides a lubricating oil composition
comprising 98 mass% or more of a lubricating base oil, with a metal
element content of 0.1 mass% or less, a sum of a phosphorus element
10 content and a sulfur element content of 0.1 mass% or less, and a
nitrogen element content of 0. I mass% or less based on a total amount
of the lubricating oil composition, wherein the lubricating base oil is a
synthetic hydrocarbon oil, and the lubricating oil composition firther
comprises at least one selected from saycosine acid derivatives and
15 amine salts of acidic phosphate; an amine antioxidant; and a
benzotriazole compound.
[0008] With the lubricating oil composition of the present invention, the
environmental impact is reduced and, at the same time, the effects of
adding additives can be effectively obtained by the use of at least one
20 selected from sascosine acid derivatives and arnine salts of acidic
phosphate, an amine antioxidant, and a benzotsiawle compound in
combination as additives.
[0009] Conventional lubricating oil compositions have been used in
facilities such as factories where measwes to prevent the leakage of
25 lubricating oil co~npositionsa re sufficiently implemented, but recently,
lubricating oil compositions are increasingly used in residential areas as
well (for example, the use of lubricating oil compositions at service
stations). In residential areas, measures to prevent the leakage of
lubricating oil compositions are not necessarily implemented in a
sufficient manner, and it is realistically impossible to implement such
5 measures sufficiently. On the other hand, the lubricating oil
composition of the present invention has excellent demulsibility and,
therefore, even when the leaked lubricating oil composition comes into
contact with rain water or the like, the lubricating oil composition can
be separated horn water and recovered, and thus environmental impact
10 can be reduced.
[0010] It is preferable that the amine antioxidant comprises an alkylated
phenyl-a-naphthylamine and an allcylated diphenylamine.
[0011] It is preferable that the alkylated phenyl-a-naphthylamine has an
alkyl group having 6 to 20 carbon atoms.
15 [0012] It is preferable that the synthetic hydrocarbon oil comprises a
poly-a-olefin, and the poly-a-olefin provides fragment peaks that
satisfy conditions represented by the following formula (1) in
FD-MASS analysis:
ABI1.0 (1)
20 wherein A represents a peak intensity of a fragment having a mass ww)
of 422, and B represents a total peak intensity of Cagments having
masses (Mw) of 590, 506, and 338.
[0013] The above lubricating oil composition is suitably used for an
apparatus for producing at least one selected fkom foods, cosmetics, and
25 containers for storage thereof
Advalltageous Effects of Invention
[0014] According to the present invention, it is possible to provide a
lubricating oil composition in which the metal element, phosplloius
element, s u l k element, and nitrogen element contents are small, the
environmental impact of which can be reduced, and from which the
5 effect of adding additives can be effectively obtained,
Description of Embodiments
[0015] Preferred embodiments of the present invention will now be
described in detail below,
[0016] In the lubricating oil composition of the present embodiment,
10 the metal element content is 0.1 mass% or less, the sum of the
phosphorus element content and the sulfur element content is 0.1
mass% or less, and the nitrogen element content is 0.1 mass% or less
based on the total amount of the lubricating oil composition. The
lubricating oil composition of the present embodiment comprises 98
15 mass% or more of a synthetic hydrocarbon oil based on the total amount
of the lubricating oil composition; at least one selected from sarcosine
acid derivatives and amine salts of acidic phosphate; an amine
antioxidant; and a benzotriazole compound.
[0017] From the viewpoint of extending the life of the lubricating oil
20 composition and obtaining excellent demulsibility, the lubricating oil
composition comprises a synthetic hydrocarbon oil as a lubricating base
oil. Examples of the synthetic hydrocarbon oil include poly-a-olefins
or hydrides thereof. Also usable are olefin oligomers; waxes such as
slack wax and FT wax, and base oils obtained by isomesizing such
25 waxes; those containing aromatic compounds andlor unsaturated
compounds (for example, those obtained by hydrogenating a distillate
fraction of terpene oil or crude oil); and synthetic aromatic
hydrocarbons such as alkylbenzenes and alkylnaphthalenes. Among
these, it is preferable to use a poly-a-olefin or a hydride thereof. It is
also preferable to use a poly-a-olefin in combination with a highly
5 viscous olefm oligomer or a hydride thereof.
[0018] From the viewpoint of the stability and demulsibility of the
lubricating oil composition, the poly-a-olefin is preferably a
poly-a-olefin that provides fragment peaks satisfying the conditions
represented by the following formula (I) in FD-MASS analysis:
10 M3s1.0 (1)
wherein A represents the peak intensity of a fragment having a mass
(Mw) of 422, and J3 represents the total peak intensity of fragments
having masses (Mw) of 590,506, and 338.
[0019] Exemplay measurement conditions of FD-MASS analysis may
15 be as follows.
Apparatus: JMS-700y manufactured by JEOL Ltd.
Measurement conditions: ionizing method FD+, accelerating voltage 6
kV, resolution 1000, measurement range 50 to 2000, emitter cusseni2
mAImin
20 [0020] The kinematic viscosity at 40°C of the synthetic hydrocarbon oil
is preferably 8 mm2/s or more, more preferably 15 mni21s or more, and
even more preferably 30 mm2/s or more, and is preferably 800 mm2/s or
less, more preferably 500 d s or less, and even more preferably 350
mm2/s or less. With the kinematic viscosity at 40°C of the
25 hydrocarbon oil being within this range, wear at a sliding past can be
reduced and stirring resistance can also be lowered, thus suppressing the
energy consumption.
(00211 When increasing the kinematic viscosity at 40°C of the
hydrocasbon base oil to such an extent that the kinematic viscosity
exceeds 50 mm2/s, it is preferable to use a poly-a-olefin having a
5 kinematic viscosity at 40°C of 50 mm2/s or less in combination with an
olefin oligomer having a kinematic viscosity at 40°C of 100 mm2/s or
more or a hydside thereof. In this case, it is preferable to combine
these components such that the decrease in viscosity as determined by
the KRl, shearing stability test set forth in IS0 26422 is 5% or less.
10 [0022] The kinematic viscosity at 100°C of the synthetic hydrocarbon
oil is preferably 2 mm2/s or more, more preferably 3 mm2/s or more, and
even more preferably 4 mm2/s or more, and is preferably 100 mm2/s or
less, more preferably 75 rnm2/s or less, and even more preferably 50
rnm2/s or less. With the kinematic viscosity of the hydrocarbon base
15 oil being within the above range, wear at a sliding part can be reduced
and stirring resistance can also be low, thus suppressing the energy
consumption.
[0023] The viscosity index of the synthetic hydrocarbon oil is
preferably 120 or more and more preferably 130 or more, and is
20 preferably 160 or less and more preferably 155 or less. When the
viscosity index is within the above range, the low temperature viscosity
is low and the pour point is also high.
[0024] The kinematic viscosities at 40°C and 100°C and the viscosity
index in the present invention refer to values measured in accordance
25 with JIS K 2283:2000 "Crude Petroleum and Petroleum Products -
Determination of Kinematic Viscosity and Calculation of Viscosity
Index from Kinematic Viscosity."
[0025] From the viewpoint of reducing environmental impact, the
synthetic hydrocarbon oil content is 98 mass% or more and preferably
98.5 mass% or more based on the total amount of the lubricating oil
5 composition.
[0026] The lubricating oil composition fu1-fhe.r comprises at least one
selected 50m sascosine acid derivatives and amine salts of acidic
phosphate.
[0027] Sarcosine acid derivatives ase not particularly limited and, for
10 example, compounds represented by the following formula (2) are used.
[0028] [Chemical Formula 11
[0029] In formula (2), R' represents a hydrocarbyl group having 6 to 20
carbon atoms and preferably represents a linear alkenyl group having 10
15 to 20 carbon atoms.
[0030] Amine salts of acidic phosphate ase not particularly limited, and
salts of acidic phosphates represented by the following formula (3) and
amines represented by the following formula (4) are used.
[003 11 [Chemical Formula 21
[0032] In formula (3), R' each independently represents an asyl group,
akyl group, or alkenyl group having 3 to 20 carbon atoms, and
preferably represents an aryl group, alkyl group, or alkenyl group
having 6 to 12 carbon atoms; and m represents 1 or 2. The acidic
phosphate represented by folmula (3) is preferably a mixture of an
acidic phosphate of formula (3) wherein m is 1 and an acidic phosphate
of formula (3) wherein m is 2.
5 [0033] [Chemical Fotmula 31
R~~-,NH, (4)
[0034] In folmula (4), R~ each independently represents an aryl group,
alkyl group, or alkenyl group having 6 to 20 carbon atoms, and
preferably represents an a w l group having a branched structure and 10
10 to 18 carbon atoms; and n represents an integer of 0 to 3 and preferably
represents 2.
100351 The content of the at least one selected fiom sarcosine acid
derivatives and amine salts of acidic phosphate %om the viewpoint of
imparting sufficient rust preventing properties to the lubricating oil
15 composition is preferably 0.001 mass% or more, more preferably 0.005
mass% or more, and even more preferably 0.01 mass% or more based
on the total amount of the lubricating oil composition, and, from the
viewpoint of sludge resistance, is preferably 0.1 mass% or less, more
preferably 0.05 mass% or less, and even more preferably 0.03 mass% or
20 less based on the total amount of the lubricating oil composition.
[0036] In the present embodiment, it is sufficient to use at least one
selected from sarwsine acid derivatives and amine salts of acidic
phosphate, and it is preferable to use at least one sarcosine acid
derivative and at least one amine salt of acidic phosphate in
25 combination.
[0037] The lubricating oil composition further comprises an amine
antioxidant. Examples of the amine antioxidant include alkylated
phenyl-a-naphthylarnines represented by the following forniula (5) and
(p,pl-)ablated diphenylamines represented by the following formula
(6).
5 [0038] [Chemical Formula 41
[0039] In formula (5), R4 represents an alkyl group having 1 to 16
i
! carbon atoms and preferably represents an alkyl group having 6 to 20
carbon atoms, In particular, horn the viewpoint of the demulsibility of
10 the lubricating oil composition, R4 preferably represents an allcyl group
having 8 to 18 carbon atoms.
[0040] [Chemical Formula 51
[0041] In formula (6), R5 and R~ each independently represent an allcyl
15 . group having I to 20 carbon atoms, preferably an alkyl group having 3
to 12 carbon atoms, and more preferably an alkyl group having 4 to 8
carbon atoms. Although it is preferable that R5 and R6 are different
from each other, it is difficult to synthesize a compound having only a
specific combination of R~ and R ~ . Accordingly, the (p,pl-)allcylated
20 diphenylamine represented by formula (6) is preferably a mixture of a
compound in which R' and R6 are identical with each other and a
compound in which R~ and R~ are different from each other.
[0042] From the viewpoint of extending the life of the lubricating oil
composition, the amine antioxidant content is preferably 0.4 mass% or
more and more preferably 0.8 mass% or more based on the total amount
5 of the lubricating oil composition. From the viewpoint of sludge
resistance, the amine antioxidant content is preferably 1.99 mass% or
less, more preferably 1.5 mass% or less, and even more preferably 1
mass% or less based on the total amount of the lubricating oil
composition.
10 [0043] As the amine antioxidant, it is preferable to use an alkylated
phenyl-a-naphthylamine represented by formula (5) and a
(p,pl-)alkylated diphenylamine represented by follnula (6) in
combination. The use of these components in combination
synergistically exerts the effect of extending the life of the lubricating
15 oil composition. In this case, the ratio (the mass ratio) between the
content of the alkylated phenyl-a-naphthylamine represented by
formula (5) and the content of the (p,pl-)aLkylated diphenylamine
represented by formula (6) is preferably 2:8 to 8:2 and more preferably
4:6 to 6:4.
20 [0044] The lubricating oil composition further comprises a
benzotriazole compound. The benzotriazole compound enconlpasses
benzotriazole represented by the following formula (7) and
benzotriazole derivatives such as allcylbenzotriazoles represented by the
following formula (8) and (alkyl)aminoalkylbenzotriazoles represented
25 by the following formula (9).
[0045] [Chemical Foilnula 61
[0046] [Chemical Formula 71
[0047] In formula (8), R' represents a linear or branched alkyl group
5 having 1 to 4 carbon atoms and preferably a methyl group or an ethyl
group; and a represents 1 to 3 and preferably 1 or 2.
[0048] [Chemical Formula 81
[0049] In formula (9), R' represents a linear or branched alkyl group
10 having 1 to 4 carbon atoms and preferably a methyl group or an ethyl
group; R' represents a methylene group or an ethylene group; R'O and
R" each independently represent a hydrogen atom or a linear or
branched akyl group having I to 18 carbon atoms and preferably a
linear or branched akyl group having 1 to 12 carbon atoms; and b
15 represents 0 to 3 and preferably 0 or 1.
[0050] From the viewpoint of extending the life of the lubricating oil
composition, the benmtriazole compound content is preferably 0.002
mass% or more, more preferably 0.005 mass% or more, and even more
preferably 0.02 mass% or more, and is preferably 0.5 mass% or less,
more preferably 0.5 mass% or less, and even more preferably 0.3
mass% or less based on the total amount of the lubricating oil
composition.
5 [0051] The lubricating oil composition may futther comprise other
additives as necessary. For example, anti-foaming agents, extreme
pressure agents, and the like are preferably used as other additives.
Pour point depressants, viscosity index improvers, and thickeners may
be used as other additives as well.
10 [0052] In the lubricating oil composition, the metal element content is
0.1 mass% or less, the sum of the phosphorus element content and the
sulfur element content is 0.1 mass'Xo or less, and the nitrogen element
content is 0.08 mass% or less based on the total amount of the
lubricating oil composition. The metal element content is preferably
15 0.08 mass% or less and more preferably 0.01 mass% or less based on
the total amount of the lubricating oil composition. The sum of the
phospho~we lement content and the sulfur element content is preferably
0.08 mass% or less and more preferably 0.05 mass% or less based on
the total amount of the lubricating oil composition. The nitrogen
20 element content is preferably 0.06 mass% or less and more preferably
0.05 mass% or less based on the total amount of the lubricating oil
composition.
[OD531 The metal element, phosphoius element, and sulfur elenlent
contents in the present invention refer to values measured in accordance
25 with PI-5s-38-03 "Lubricating Oils - Determination of Additive
Elements - Inductively Coupled Plasma Atomic Emission
Spectrometry". The nitrogen element content refers to a value
measured in accordance with JIS K 2609: 1998 "Crude Petroleum and
Petroleum Products - Determination of Nitrogen Content."
[0054] Although the application of the lubricating oil composition is
5 not particularly limited, examples of preferable applications include
compressor oil and turbine oil and, also, bearing oil, hydraulic oil, gear
oil, and the like are suitable. In particular, for apparatuses for
producing foods, cosmetics, or containers for the storage thereof, the
reduction of environmental impact is important as represented by
10 wastewater treatment performance and, therefore, the lubricating oil
composition of the present embodiment is suitably used for such
apparatuses.
Examples
to0551 The present invention will now be described in more detail by
15 way of examples below, but the present invention is not limited to the
examples.
[0056] The following base oils and additives were used to prepare
lubricating oil compositions having the compositions shown in Tables 1
to 3. A/B in the description of base oils below represents the ratio
20 between the peak intensity (A) of a fragment having a mass (Mw) of
' 422 and the total peak intensity (B) of fragments having masses (Mw)
of 590, 506, and 338. In the tables, the "metal element content", the
"P, S content", and the "N content" indicate the metal element content,
the sum of the phosphorus element content and the sulhr element
25 content, and the nitrogen element content in a lubricating oil
composition (all based on the total amount of the lubricating oil
composition), respectively.
COO571 (Base oil ~ ~ ~ ~ ~~~
Al: Poly-a-olefin (decene derivative, kinematic viscosity at 40°C: 46.5
mm2/s, kinematic viscosity at 100°C: 7.8 mm2/s, viscosity index: 136,
5 AA3: 1.3)
A2: Poly-a-olefin (dodecene derivative, kinematic viscosity: 42.9
d s at 40°C, kinematic viscosity at 100°C: 7.6 mm2/s, viscosity
index: 146, A/B: 0.1)
A3: Poly-a-olefm (C8-C12 mixed olefin derivative, kinematic viscosity
10 at 40°C: 48.1 mm2/s, kinematic viscosity at 100°C: 8.3 mn2/s, viscosity
index: 138, AD: 0.5)
A4: Poly-a-olefin (dodecene derivative, kinematic viscosity at 40°C:
30.8 m d s , kinematic viscosity at 100°C: 6.0 mm2/s, viscosity index:
146, A/B: less than 0.1)
15 A5: Poly-a-olefin (decene derivative, kinematic viscosity at 40°C: 412
mm2/s, kinematic viscosity at 100°C: 50 mmys, viscosity index: 186,
AIS: greater than 3)
A6: Olefin copolymer (polybutene polymer, kinematic viscosity at
100°C: 4600 rnm2/s)
20 al: Mineral oil (kinematic viscosity at 40°C: 47.4 mm2/s, kinematic
viscosity at 100°C: 7.6 mm2/s, viscosity index: 127)
[0058] (Additives)
BI: N-Oleoyl sarcosine
B2: Salt of an amine having an alkyl group having I1 to 14 carbon
25 atoms and an acidic phosphate having an alkyl group having 6 carbon
atoms
bl: Sorbitan monooleate
C1: Dodecylphenyl-0,-naphthylamine
C2: Octylphenyl-a-naphthylamine
C3: (Butylphenyl)(octylphenyl)amine
5 cl : 2,6-tert-Butyl-p-cresol
DL: N,N-Bis(2-ethylhexy1)-4-methyl-1H-benzo~iazole-l-methanamine
El: Triphenyl phosphorothionate
E2: PMA anti-foaming agent
[0059] The following RPVOT test, rust preventing property evaluation
10 test, extreme pressure property evaluation test, and demulsibility
evaluation test were performed on the lubricating oil compositions.
Results are shown in Tables 1 to 3.
[0060] WVOT test)
Measurement was performed in accordance with the "Rotating
15 Bomb Oxidation Test" set forth in JIS K 2514:1996.
[0061] (Rust preventing property evaluation test)
Measurement was performed in accordance with JIS K
2510:1998, and the result "without lust" was regarded as "good," and
the result "with rust" was regarded as "poor."
20 [0062] (Extreme pressure property evaluation test)
In accordance with ASTM D4172 (2010), evaluations were
made by measuring the wear track diameter [mm] of a steel ball at rooni
temperature (oil temperature) at a rotational speed of 1200 rpm under a
load of 30 kgf for a test time of 1 hr.
25 [0063] (Demulsibility evaluation test)
Measurement was performed in accordance with the
demulsibility testing method of JIS K 2520:2000.
COO641 [Table 11
[0065] [Table 21
Composition of base
[based on the total
amount of base oil,
mass%]
Composition of
lubricating oil
cornposition
[based on the total
amount of lubricating
oil composition,
mass%]
Base oil k
1 E
Metal element content [mass%]
I p, s content [mass%]
I Rust preventing property
evaluation test
Exaniple
6
Balance
0.01
0.0005
Less than
0.01
Less than
0.01
0.045
48.3
3,058
Good
- 12 ~- - 100
Balance Balance Balance Balance
0.01 0.02 0.02
0.2 0.2 -
0.008
Less than Less than
0.01 1 0.01 1 0.01 1 0.01
Less Lenss n thi an o,lo 0.10 0.09
Good I Good I Good I Good
[0066] [Table 31
N content [mass%]
Kinematic viscosity at 40°C
[1m12/s]
RE'VOT test [min]
Rust preventing property
evaluation test
Extreme pressure property
evaluation test [m]
Demulsibility evaluation test
Immin)l
46.5
63
Poor
0,56
40-40-0
(5)
46.4
3,384
Poor
0.55
40-40-0
(5)
46.5
563
Good
0.57
40-40-0
(5)
46.4
1,303
Poor
0.39
40-38-2
(25)
46.6
1,313
Good
0.36
60 min or
more

CLAIMS
1. A lubricating oil composition comprising:
98 mass% or more of a lubricating base oil, with a metal
element content of 0.1 mass% or less, a sum of a phosphol-us element
5 content and a sulfur element content of 0.1 mass% or less, and a
nitrogen element content of 0.1 mass% or less, based on a total amount
of the lubricating oil composition, wherein
the lubricating base oil is a synthetic hydrocarbon oil, and
the lubricating oil composition krther comprises:
10 at least one selected from sarcosine acid derivatives and amine
salts of acidic phosphate;
an amine antioxidant; and
a bemtriazole compound.
2. The lubricating oil composition according to claim 1, wherein
15 the amine antioxidant comprises an alkylated phenyl-a-naphthylamine
and an allcylated diphenylamine.
3. The lubricating oil composition according to claim 2, wherein
the alkylated phenyl-a-naphthylamine has an allcyl group having 6 to 20
carbon atoms.
20 4. The lubricating oil composition according to any one of claims 1
to 3, wherein
the synthetic hydrocarbon oil comprises a poly-a-olefm, and
the poly-a-olefin provides fiagment peaks that satisfy conditions
represented by the following formula (1) in FD-MASS analysis:
25 AA321.0 (1)
wherein A represents a peak intensity of a kagment having a mass (Mw)
of 422, and B represents a total peak intensity of fiagrnents having
masses (Mw) of 590, 506, and 338. -
5. The lubricating oil composition according to any one of claims 1
to 4, for use in an apparatus for producing at least one selected from
5 foods, cosmetics, and containers for storage thereof.